fed-sx-m2: Step 9c — auto-Accept backfill drain + 6 tests

maybe_auto_accept/3 in http_server.erl now calls maybe_backfill/3
after the Accept publish. Flow:

  inbound Follow{actor: bob, object: alice, backfill: SPEC} lands
    -> pipeline ok -> append_inbox + broadcast (Step 6b)
    -> maybe_auto_accept fires (Step 6c)
       -> publish Accept{actor: alice, object: Follow} (Step 6c)
       -> maybe_backfill (Step 9c)
          -> backfill_enabled cfg gate
          -> :backfill present on Follow
          -> backfill:parse_mode -> Mode
          -> nx_kernel:log_state_for(alice) -> LogState
          -> backfill:slice(Mode, LogState, true) -> [Wrapped]
          -> deliver_backfill(bob, Slice):
               whereis(bob) cfg gate (peer worker registered)
               -> delivery_worker:enqueue(bob, A) for each

Cfg surface:
  {backfill_enabled, true}     gate the drain (default off)
  {auto_accept_follows, true}  Step 6c gate (required)

Each backfilled entry carries {backfilled, true} (per design §13.3,
:id preserved so the receiver's replay defence still catches the
forward-going copy).

6/6 in next/tests/backfill_drain.sh:
  - Follow with {backfill, {last_n, 2}} + 3 pre-published notes
    -> bob's delivery_worker has exactly 2 pending entries
  - Each entry carries {backfilled, true}
  - :backfill_enabled absent -> no drain (back-compat)
  - Follow without :backfill field -> no drain
  - Missing peer worker (no whereis) -> silently skipped + 202

Step 9 fully closed (9a slicing + 9b ?since route + 9c
Accept-drain). The live HTTP dispatch of the queued entries
still gates on Blockers #2 (httpc).

lib/erlang/runtime.sx

@@ -956,8 +956,118 @@
         (= ty "nil") (er-mk-nil)
         :else v))))
 
+;; ── HTTP request/response marshaling (Step 8b-start) ────────────
+;; The native `http-listen` primitive hands the handler an SX dict
+;;   {:method :path :query :headers :body}
+;; and expects an SX dict back
+;;   {:status :headers :body}
+;; This layer converts so Erlang handlers see proper proplists:
+;;   [{method, <<"GET">>}, {path, <<"/foo">>}, {query, <<>>},
+;;    {headers, [{<<"content-type">>, <<"text/plain">>}, ...]},
+;;    {body, <<...>>}]
+;; Headers ride as a nested proplist with binary keys — header names
+;; are arbitrary user input, so they stay out of the atom table. The
+;; outer request keys (method/path/query/headers/body) are fixed and
+;; small, so they become atoms (cheap to pattern-match against).
 
+(define er-of-sx-deep
+  (fn (v)
+    (cond
+      (= (type-of v) "dict") (er-dict-to-header-proplist v)
+      :else (er-of-sx v))))
 
+(define er-dict-to-header-proplist
+  (fn (d)
+    (let ((ks (keys d)) (out (er-mk-nil)))
+      (for-each
+        (fn (i)
+          (let ((idx (- (- (len ks) 1) i)))
+            (let ((k (nth ks idx)))
+              (let ((v (get d k)))
+                (set!
+                  out
+                  (er-mk-cons
+                    (er-mk-tuple
+                      (list
+                        (er-mk-binary (map char->integer (string->list k)))
+                        (er-of-sx-deep v)))
+                    out))))))
+        (range 0 (len ks)))
+      out)))
+
+(define er-request-dict-to-proplist
+  (fn (d)
+    (cond
+      (not (= (type-of d) "dict")) (er-of-sx d)
+      :else
+        (let ((ks (keys d)) (out (er-mk-nil)))
+          (for-each
+            (fn (i)
+              (let ((idx (- (- (len ks) 1) i)))
+                (let ((k (nth ks idx)))
+                  (let ((v (get d k)))
+                    (set!
+                      out
+                      (er-mk-cons
+                        (er-mk-tuple
+                          (list (er-mk-atom k) (er-of-sx-deep v)))
+                        out))))))
+            (range 0 (len ks)))
+          out))))
+
+;; Inverse: handler's proplist response -> SX dict for native send.
+;; Value rules:
+;;   Erlang binary   -> SX string (bytes joined)
+;;   Erlang integer  -> SX number passthrough
+;;   Erlang cons of 2-tuples -> nested SX dict (e.g. headers)
+;;   Erlang cons (other shapes) -> SX list via er-to-sx
+;;   anything else   -> er-to-sx passthrough
+
+(define er-proplist-2tuple?
+  (fn (v)
+    (cond
+      (er-nil? v) true
+      (er-cons? v)
+        (let ((h (get v :head)))
+          (cond
+            (and (er-tuple? h) (= (len (get h :elements)) 2))
+              (er-proplist-2tuple? (get v :tail))
+            :else false))
+      :else false)))
+
+(define er-to-sx-deep
+  (fn (v)
+    (cond
+      (er-binary? v) (list->string (map integer->char (get v :bytes)))
+      (and (er-cons? v) (er-proplist-2tuple? v)) (er-proplist-to-dict v)
+      :else (er-to-sx v))))
+
+(define er-proplist-to-dict
+  (fn (pl)
+    (let ((d (dict)))
+      (er-proplist-fill! pl d)
+      d)))
+
+(define er-proplist-fill!
+  (fn (pl d)
+    (cond
+      (er-nil? pl) nil
+      (er-cons? pl)
+        (let ((head (get pl :head)) (tail (get pl :tail)))
+          (cond
+            (and (er-tuple? head) (= (len (get head :elements)) 2))
+              (let ((kv (get head :elements)))
+                (let ((k (nth kv 0)) (v (nth kv 1)))
+                  (let ((key-str
+                          (cond
+                            (er-atom? k) (get k :name)
+                            (er-binary? k)
+                              (list->string (map integer->char (get k :bytes)))
+                            :else (str k))))
+                    (dict-set! d key-str (er-to-sx-deep v))
+                    (er-proplist-fill! tail d))))
+            :else (er-proplist-fill! tail d)))
+      :else nil)))
 
 ;; Load an Erlang module declaration. Source must start with
 ;; `-module(Name).` and contain function definitions. Functions
@@ -1468,9 +1578,26 @@
 ;; entry is keyed by "Module/Name/Arity"; multi-arity BIFs register
 ;; once per arity. Called eagerly at the end of runtime.sx so the
 ;; registry is ready before any erlang-eval-ast call.
-(define er-register-builtin-bifs!
-  (fn ()
-    ;; erlang module — type predicates (all pure)
+(define
+  er-bif-http-listen
+  (fn
+    (vs)
+    (let
+      ((port (nth vs 0)) (handler (nth vs 1)))
+      (cond
+        (not (= (type-of port) "number"))
+        (raise (er-mk-error-marker (er-mk-atom "badarg")))
+        (not (er-fun? handler))
+        (raise (er-mk-error-marker (er-mk-atom "badarg")))
+        :else (let
+          ((sx-handler (fn (req-dict) (er-http-resp-to-sx (er-apply-fun handler (list (er-http-req-of-sx req-dict)))))))
+          (http-listen port sx-handler))))))
+
+;; Register everything at load time.
+(define
+  er-register-builtin-bifs!
+  (fn
+    ()
     (er-register-pure-bif! "erlang" "is_integer" 1 er-bif-is-integer)
     (er-register-pure-bif! "erlang" "is_atom" 1 er-bif-is-atom)
     (er-register-pure-bif! "erlang" "is_list" 1 er-bif-is-list)
@@ -1479,27 +1606,61 @@
     (er-register-pure-bif! "erlang" "is_float" 1 er-bif-is-float)
     (er-register-pure-bif! "erlang" "is_boolean" 1 er-bif-is-boolean)
     (er-register-pure-bif! "erlang" "is_pid" 1 er-bif-is-pid)
-    (er-register-pure-bif! "erlang" "is_reference" 1 er-bif-is-reference)
+    (er-register-pure-bif!
+      "erlang"
+      "is_reference"
+      1
+      er-bif-is-reference)
     (er-register-pure-bif! "erlang" "is_binary" 1 er-bif-is-binary)
-    (er-register-pure-bif! "erlang" "is_function" 1 er-bif-is-function)
-    (er-register-pure-bif! "erlang" "is_function" 2 er-bif-is-function)
-    ;; erlang module — pure data ops
+    (er-register-pure-bif!
+      "erlang"
+      "is_function"
+      1
+      er-bif-is-function)
+    (er-register-pure-bif!
+      "erlang"
+      "is_function"
+      2
+      er-bif-is-function)
     (er-register-pure-bif! "erlang" "length" 1 er-bif-length)
     (er-register-pure-bif! "erlang" "hd" 1 er-bif-hd)
     (er-register-pure-bif! "erlang" "tl" 1 er-bif-tl)
     (er-register-pure-bif! "erlang" "element" 2 er-bif-element)
     (er-register-pure-bif! "erlang" "tuple_size" 1 er-bif-tuple-size)
     (er-register-pure-bif! "erlang" "byte_size" 1 er-bif-byte-size)
-    (er-register-pure-bif! "erlang" "atom_to_list" 1 er-bif-atom-to-list)
-    (er-register-pure-bif! "erlang" "list_to_atom" 1 er-bif-list-to-atom)
+    (er-register-pure-bif!
+      "erlang"
+      "atom_to_list"
+      1
+      er-bif-atom-to-list)
+    (er-register-pure-bif!
+      "erlang"
+      "list_to_atom"
+      1
+      er-bif-list-to-atom)
     (er-register-pure-bif! "erlang" "abs" 1 er-bif-abs)
     (er-register-pure-bif! "erlang" "min" 2 er-bif-min)
     (er-register-pure-bif! "erlang" "max" 2 er-bif-max)
-    (er-register-pure-bif! "erlang" "tuple_to_list" 1 er-bif-tuple-to-list)
-    (er-register-pure-bif! "erlang" "list_to_tuple" 1 er-bif-list-to-tuple)
-    (er-register-pure-bif! "erlang" "integer_to_list" 1 er-bif-integer-to-list)
-    (er-register-pure-bif! "erlang" "list_to_integer" 1 er-bif-list-to-integer)
-    ;; erlang module — process / runtime (side-effecting)
+    (er-register-pure-bif!
+      "erlang"
+      "tuple_to_list"
+      1
+      er-bif-tuple-to-list)
+    (er-register-pure-bif!
+      "erlang"
+      "list_to_tuple"
+      1
+      er-bif-list-to-tuple)
+    (er-register-pure-bif!
+      "erlang"
+      "integer_to_list"
+      1
+      er-bif-integer-to-list)
+    (er-register-pure-bif!
+      "erlang"
+      "list_to_integer"
+      1
+      er-bif-list-to-integer)
     (er-register-bif! "erlang" "self" 0 er-bif-self)
     (er-register-bif! "erlang" "spawn" 1 er-bif-spawn)
     (er-register-bif! "erlang" "spawn" 3 er-bif-spawn)
@@ -1515,12 +1676,16 @@
     (er-register-bif! "erlang" "unregister" 1 er-bif-unregister)
     (er-register-bif! "erlang" "whereis" 1 er-bif-whereis)
     (er-register-bif! "erlang" "registered" 0 er-bif-registered)
-    ;; erlang module — exception raising (modelled as side-effecting)
-    (er-register-bif! "erlang" "throw" 1
+    (er-register-bif!
+      "erlang"
+      "throw"
+      1
       (fn (vs) (raise (er-mk-throw-marker (er-bif-arg1 vs "throw")))))
-    (er-register-bif! "erlang" "error" 1
+    (er-register-bif!
+      "erlang"
+      "error"
+      1
       (fn (vs) (raise (er-mk-error-marker (er-bif-arg1 vs "error")))))
-    ;; lists module — all pure
     (er-register-pure-bif! "lists" "reverse" 1 er-bif-lists-reverse)
     (er-register-pure-bif! "lists" "map" 2 er-bif-lists-map)
     (er-register-pure-bif! "lists" "foldl" 3 er-bif-lists-foldl)
@@ -1534,11 +1699,13 @@
     (er-register-pure-bif! "lists" "filter" 2 er-bif-lists-filter)
     (er-register-pure-bif! "lists" "any" 2 er-bif-lists-any)
     (er-register-pure-bif! "lists" "all" 2 er-bif-lists-all)
-    (er-register-pure-bif! "lists" "duplicate" 2 er-bif-lists-duplicate)
-    ;; io module — side-effecting (writes to io buffer)
+    (er-register-pure-bif!
+      "lists"
+      "duplicate"
+      2
+      er-bif-lists-duplicate)
     (er-register-bif! "io" "format" 1 er-bif-io-format)
     (er-register-bif! "io" "format" 2 er-bif-io-format)
-    ;; ets module — side-effecting (mutates table state)
     (er-register-bif! "ets" "new" 2 er-bif-ets-new)
     (er-register-bif! "ets" "insert" 2 er-bif-ets-insert)
     (er-register-bif! "ets" "lookup" 2 er-bif-ets-lookup)
@@ -1546,23 +1713,88 @@
     (er-register-bif! "ets" "delete" 2 er-bif-ets-delete)
     (er-register-bif! "ets" "tab2list" 1 er-bif-ets-tab2list)
     (er-register-bif! "ets" "info" 2 er-bif-ets-info)
-    ;; code module — side-effecting (mutates module registry, kills procs)
     (er-register-bif! "code" "load_binary" 3 er-bif-code-load-binary)
     (er-register-bif! "code" "purge" 1 er-bif-code-purge)
     (er-register-bif! "code" "soft_purge" 1 er-bif-code-soft-purge)
     (er-register-bif! "code" "which" 1 er-bif-code-which)
     (er-register-bif! "code" "is_loaded" 1 er-bif-code-is-loaded)
     (er-register-bif! "code" "all_loaded" 0 er-bif-code-all-loaded)
-    ;; file module
     (er-register-bif! "file" "read_file" 1 er-bif-file-read-file)
     (er-register-bif! "file" "write_file" 2 er-bif-file-write-file)
     (er-register-bif! "file" "delete" 1 er-bif-file-delete)
-    ;; Phase 8 FFI — host-primitive BIFs (loops/fed-prims)
     (er-register-pure-bif! "crypto" "hash" 2 er-bif-crypto-hash)
     (er-register-pure-bif! "cid" "from_bytes" 1 er-bif-cid-from-bytes)
     (er-register-pure-bif! "cid" "to_string" 1 er-bif-cid-to-string)
+    (define
+      er-bif-binary-to-list
+      (fn
+        (vs)
+        (let
+          ((v (nth vs 0)))
+          (cond
+            (not (er-binary? v))
+            (raise (er-mk-error-marker (er-mk-atom "badarg")))
+            :else (let
+              ((bs (get v :bytes)) (out (er-mk-nil)))
+              (for-each
+                (fn
+                  (i)
+                  (set!
+                    out
+                    (er-mk-cons (nth bs (- (- (len bs) 1) i)) out)))
+                (range 0 (len bs)))
+              out)))))
+    (define
+      er-iolist-walk!
+      (fn
+        (v acc fail)
+        (cond
+          (nth fail 0)
+          nil
+          (er-nil? v)
+          nil
+          (er-cons? v)
+          (do
+            (er-iolist-walk! (get v :head) acc fail)
+            (er-iolist-walk! (get v :tail) acc fail))
+          (er-binary? v)
+          (for-each
+            (fn (i) (append! acc (nth (get v :bytes) i)))
+            (range 0 (len (get v :bytes))))
+          (= (type-of v) "number")
+          (cond
+            (and (>= v 0) (<= v 255))
+            (append! acc v)
+            :else (set-nth! fail 0 true))
+          :else (set-nth! fail 0 true))))
+    (define
+      er-bif-list-to-binary
+      (fn
+        (vs)
+        (let
+          ((v (nth vs 0)) (acc (list)) (fail (list false)))
+          (cond
+            (not (or (er-nil? v) (er-cons? v) (er-binary? v)))
+            (raise (er-mk-error-marker (er-mk-atom "badarg")))
+            :else (do
+              (er-iolist-walk! v acc fail)
+              (cond
+                (nth fail 0)
+                (raise (er-mk-error-marker (er-mk-atom "badarg")))
+                :else (er-mk-binary acc)))))))
     (er-register-bif! "file" "list_dir" 1 er-bif-file-list-dir)
+    (er-register-pure-bif!
+      "erlang"
+      "binary_to_list"
+      1
+      er-bif-binary-to-list)
+    (er-register-pure-bif!
+      "erlang"
+      "list_to_binary"
+      1
+      er-bif-list-to-binary)
     (er-mk-atom "ok")))
 
-;; Register everything at load time.
+(er-register-bif! "http" "listen" 2 er-bif-http-listen)
+
 (er-register-builtin-bifs!)

lib/erlang/scoreboard.json

@@ -1,18 +1,18 @@
 {
   "language": "erlang",
-  "total_pass": 729,
-  "total": 729,
+  "total_pass": 761,
+  "total": 761,
   "suites": [
     {"name":"tokenize","pass":62,"total":62,"status":"ok"},
     {"name":"parse","pass":52,"total":52,"status":"ok"},
-    {"name":"eval","pass":385,"total":385,"status":"ok"},
+    {"name":"eval","pass":408,"total":408,"status":"ok"},
     {"name":"runtime","pass":93,"total":93,"status":"ok"},
     {"name":"ring","pass":4,"total":4,"status":"ok"},
     {"name":"ping-pong","pass":4,"total":4,"status":"ok"},
     {"name":"bank","pass":8,"total":8,"status":"ok"},
     {"name":"echo","pass":7,"total":7,"status":"ok"},
     {"name":"fib","pass":8,"total":8,"status":"ok"},
-    {"name":"ffi","pass":28,"total":28,"status":"ok"},
+    {"name":"ffi","pass":37,"total":37,"status":"ok"},
     {"name":"vm","pass":78,"total":78,"status":"ok"}
   ]
 }

lib/erlang/scoreboard.md

@@ -1,19 +1,19 @@
 # Erlang-on-SX Scoreboard
 
-**Total: 729 / 729 tests passing**
+**Total: 761 / 761 tests passing**
 
 |  | Suite | Pass | Total |
 |---|---|---|---|
 | ✅ | tokenize | 62 | 62 |
 | ✅ | parse | 52 | 52 |
-| ✅ | eval | 385 | 385 |
+| ✅ | eval | 408 | 408 |
 | ✅ | runtime | 93 | 93 |
 | ✅ | ring | 4 | 4 |
 | ✅ | ping-pong | 4 | 4 |
 | ✅ | bank | 8 | 8 |
 | ✅ | echo | 7 | 7 |
 | ✅ | fib | 8 | 8 |
-| ✅ | ffi | 28 | 28 |
+| ✅ | ffi | 37 | 37 |
 | ✅ | vm | 78 | 78 |
 
 

lib/erlang/tests/eval.sx

@@ -228,9 +228,10 @@
 (er-eval-test "tuple_size 0" (ev "tuple_size({})") 0)
 
 ;; ── BIFs: atom / list conversions ───────────────────────────────
-(er-eval-test "atom_to_list" (ev "atom_to_list(hello)") "hello")
+(er-eval-test "atom_to_list -> charlist length" (ev "length(atom_to_list(hello))") 5)
+(er-eval-test "atom_to_list -> head $h" (ev "hd(atom_to_list(hello))") 104)
 (er-eval-test "list_to_atom roundtrip"
-  (nm (ev "list_to_atom(atom_to_list(foo))")) "foo")
+  (nm (ev "list_to_atom(atom_to_list(foo))")) "foo")  ;; round-trip via charlist
 (er-eval-test "list_to_atom fresh"
   (nm (ev "list_to_atom(\"bar\")")) "bar")
 
@@ -1060,11 +1061,13 @@
 (er-eval-test "list_to_tuple roundtrip"
   (ev "tuple_size(list_to_tuple([10, 20, 30]))") 3)
 
-(er-eval-test "integer_to_list" (ev "integer_to_list(42)") "42")
-(er-eval-test "integer_to_list neg" (ev "integer_to_list(-99)") "-99")
+(er-eval-test "integer_to_list -> charlist length" (ev "length(integer_to_list(42))") 2)
+(er-eval-test "integer_to_list 42 head $4" (ev "hd(integer_to_list(42))") 52)
+(er-eval-test "integer_to_list neg -> charlist length" (ev "length(integer_to_list(-99))") 3)
+(er-eval-test "integer_to_list -99 head $-" (ev "hd(integer_to_list(-99))") 45)
 (er-eval-test "list_to_integer" (ev "list_to_integer(\"123\")") 123)
 (er-eval-test "list_to_integer roundtrip"
-  (ev "list_to_integer(integer_to_list(7))") 7)
+  (ev "list_to_integer(integer_to_list(7))") 7)  ;; round-trip via charlist
 
 (er-eval-test "is_function fun"
   (nm (ev "F = fun (X) -> X end, is_function(F)")) "true")
@@ -1341,6 +1344,42 @@
   (get (nth (get er-rt-cap-result :elements) 4) :name) "true")
 
 
+
+;; ── $X char literals (Step 3b substrate fix 2026-06-04) ──────────
+(er-eval-test "char $A" (ev "$A") 65)
+(er-eval-test "char $a" (ev "$a") 97)
+(er-eval-test "char $0 is digit, not escape-NUL" (ev "$0") 48)
+(er-eval-test "char $\\n is newline (10)" (ev "$\\n") 10)
+(er-eval-test "char $\\t is tab (9)" (ev "$\\t") 9)
+(er-eval-test "char $\\r is CR (13)" (ev "$\\r") 13)
+(er-eval-test "char $\\s is space (32)" (ev "$\\s") 32)
+(er-eval-test "char $\\0 is NUL (0)" (ev "$\\0") 0)
+(er-eval-test "char $\\\\ is backslash (92)" (ev "$\\\\") 92)
+(er-eval-test "[$h,$i] head is 104" (ev "hd([$h, $i])") 104)
+(er-eval-test "list_to_binary char-list -> bytes"
+  (ev "byte_size(list_to_binary([$f, $e, $d]))") 3)
+(er-eval-test "list_to_binary char-list round-trip"
+  (nm (ev "list_to_binary([$h, $i]) =:= <<104, 105>>")) "true")
+
+
+;; ── atom_to_list / integer_to_list charlist semantics (Step 3b substrate fix #3) ──
+(er-eval-test "atom_to_list hd is char code"
+  (ev "hd(atom_to_list(hi))") 104)
+(er-eval-test "atom_to_list maps to bytes via list_to_binary"
+  (ev "byte_size(list_to_binary(atom_to_list(hello)))") 5)
+(er-eval-test "atom_to_list -> list_to_binary -> bytes content"
+  (nm (ev "list_to_binary(atom_to_list(ok)) =:= <<111, 107>>")) "true")
+(er-eval-test "integer_to_list 12345 -> 5 chars"
+  (ev "length(integer_to_list(12345))") 5)
+(er-eval-test "integer_to_list -> bytes -> back"
+  (ev "list_to_integer(integer_to_list(99999))") 99999)
+(er-eval-test "list_to_atom from charlist"
+  (nm (ev "list_to_atom([$f, $o, $o])")) "foo")
+(er-eval-test "list_to_atom from SX-string back-compat"
+  (nm (ev "list_to_atom(\"bar\")")) "bar")
+(er-eval-test "list_to_integer from charlist"
+  (ev "list_to_integer([$1, $0, $0])") 100)
+
 (define
   er-eval-test-summary
   (str "eval " er-eval-test-pass "/" er-eval-test-count))

lib/erlang/tests/ffi.sx

@@ -160,6 +160,51 @@
   (ffi-nm (ffi-ev "element(2, file:list_dir(\"/no/such/dir/xyz\"))"))
   "enoent")
 
+(er-ffi-test
+  "binary_to_list <<1,2,3>> length"
+  (ffi-ev "length(binary_to_list(<<1,2,3,4,5>>))")
+  5)
+
+(er-ffi-test
+  "binary_to_list hd byte"
+  (ffi-ev "hd(binary_to_list(<<7,8,9>>))")
+  7)
+
+(er-ffi-test
+  "binary_to_list empty -> []"
+  (ffi-nm (ffi-ev "case binary_to_list(<<>>) of [] -> empty end"))
+  "empty")
+
+(er-ffi-test
+  "list_to_binary flat list bytes"
+  (ffi-ev "byte_size(list_to_binary([1,2,3]))")
+  3)
+
+(er-ffi-test
+  "list_to_binary nested iolist"
+  (ffi-ev "byte_size(list_to_binary([1, <<2,3>>, [4, [5]]]))")
+  5)
+
+(er-ffi-test
+  "list_to_binary round-trip via binary_to_list"
+  (ffi-nm (ffi-ev "list_to_binary(binary_to_list(<<10,20,30>>)) =:= <<10,20,30>>"))
+  "true")
+
+(er-ffi-test
+  "binary_to_list non-binary -> error:badarg"
+  (ffi-nm (ffi-ev "try binary_to_list(42) catch error:badarg -> ok end"))
+  "ok")
+
+(er-ffi-test
+  "list_to_binary out-of-range byte -> error:badarg"
+  (ffi-nm (ffi-ev "try list_to_binary([300]) catch error:badarg -> ok end"))
+  "ok")
+
+(er-ffi-test
+  "list_to_binary non-iolist -> error:badarg"
+  (ffi-nm (ffi-ev "try list_to_binary(42) catch error:badarg -> ok end"))
+  "ok")
+
 ;; ── Still deferred (no host primitive): httpc (HTTP client, v2),
 ;; sqlite-* (v2 indexes). Assert NOT registered so a future iteration
 ;; that wires them without updating this suite fails fast.

lib/erlang/tokenizer.sx

@@ -229,13 +229,37 @@
                 (= ch "$")
                 (do
                   (er-advance! 1)
-                  (if
-                    (and (< pos src-len) (= (er-cur) "\\"))
-                    (do
-                      (er-advance! 1)
-                      (when (< pos src-len) (er-advance! 1)))
-                    (when (< pos src-len) (er-advance! 1)))
-                  (er-emit! "integer" (slice src start pos) start)
+                  ;; Emit the char's decimal code as the integer token value
+                  ;; (was: raw "$X" text — parse-number then returned nil).
+                  (let
+                    ((code (cond
+                       (>= pos src-len) 0
+                       (= (er-cur) "\\")
+                         (do
+                           (er-advance! 1)
+                           (let ((esc (if (< pos src-len) (er-cur) "")))
+                             (when (< pos src-len) (er-advance! 1))
+                             (cond
+                               (= esc "n")  10
+                               (= esc "t")  9
+                               (= esc "r")  13
+                               (= esc "s")  32
+                               (= esc "b")  8
+                               (= esc "e")  27
+                               (= esc "f")  12
+                               (= esc "v")  11
+                               (= esc "d")  127
+                               (= esc "0")  0
+                               (= esc "\\")  92
+                               (= esc "\"") 34
+                               (= esc "'")  39
+                               (= esc "")   0
+                               :else (char->integer (nth (string->list esc) 0)))))
+                       :else
+                         (let ((c (er-cur)))
+                           (er-advance! 1)
+                           (char->integer (nth (string->list c) 0))))))
+                    (er-emit! "integer" (str code) start))
                   (scan!))
                 (er-lower? ch)
                 (do

lib/erlang/transpile.sx

@@ -107,7 +107,12 @@
     (let
       ((ty (get node :type)))
       (cond
-        (= ty "integer") (parse-number (get node :value))
+        (= ty "integer")
+          (let ((n (parse-number (get node :value))))
+            (cond
+              (= n nil) (error (str "Erlang: invalid integer literal: "
+                                     (get node :value)))
+              :else (truncate n)))
         (= ty "float") (parse-number (get node :value))
         (= ty "atom") (er-mk-atom (get node :value))
         (= ty "string") (get node :value)
@@ -821,16 +826,30 @@
         (len (get v :elements))
         (error "Erlang: tuple_size: not a tuple")))))
 
+(define er-string->charlist
+  (fn (s)
+    (let ((cs (string->list s)) (out (er-mk-nil)))
+      (for-each
+        (fn (i)
+          (set! out (er-mk-cons
+                      (char->integer (nth cs (- (- (len cs) 1) i)))
+                      out)))
+        (range 0 (len cs)))
+      out)))
+
 (define
   er-bif-atom-to-list
   (fn
     (vs)
     (let
       ((v (er-bif-arg1 vs "atom_to_list")))
+      ;; Standard Erlang: atom_to_list/1 returns an Erlang charlist
+      ;; (list of integer char codes). Was: SX string of :name —
+      ;; unusable from Erlang-land for [Char|T] / ++ / binary segments.
       (if
         (er-atom? v)
-        (get v :name)
-        (error "Erlang: atom_to_list: not an atom")))))
+        (er-string->charlist (get v :name))
+        (raise (er-mk-error-marker (er-mk-atom "badarg")))))))
 
 (define
   er-bif-list-to-atom
@@ -838,10 +857,11 @@
     (vs)
     (let
       ((v (er-bif-arg1 vs "list_to_atom")))
-      (if
-        (= (type-of v) "string")
-        (er-mk-atom v)
-        (error "Erlang: list_to_atom: not a string")))))
+      ;; Accept Erlang charlist (cons of ints) or SX string.
+      (let ((s (er-source-to-string v)))
+        (cond
+          (= s nil) (raise (er-mk-error-marker (er-mk-atom "badarg")))
+          :else (er-mk-atom s))))))
 
 ;; ── lists module ─────────────────────────────────────────────────
 (define
@@ -1597,10 +1617,12 @@
     (vs)
     (let
       ((v (er-bif-arg1 vs "integer_to_list")))
+      ;; Standard Erlang: integer_to_list/1 returns an Erlang charlist
+      ;; (e.g. integer_to_list(42) -> [$4, $2] -> [52, 50]).
       (cond
         (not (= (type-of v) "number"))
         (raise (er-mk-error-marker (er-mk-atom "badarg")))
-        :else (str v)))))
+        :else (er-string->charlist (str v))))))
 
 (define
   er-bif-list-to-integer
@@ -1608,15 +1630,14 @@
     (vs)
     (let
       ((v (er-bif-arg1 vs "list_to_integer")))
-      (cond
-        (not (= (type-of v) "string"))
-        (raise (er-mk-error-marker (er-mk-atom "badarg")))
-        :else (let
-          ((n (parse-number v)))
-          (cond
-            (= n nil)
-            (raise (er-mk-error-marker (er-mk-atom "badarg")))
-            :else n))))))
+      ;; Accept Erlang charlist (cons of ints) or SX string.
+      (let ((s (er-source-to-string v)))
+        (cond
+          (= s nil) (raise (er-mk-error-marker (er-mk-atom "badarg")))
+          :else (let ((n (parse-number s)))
+            (cond
+              (= n nil) (raise (er-mk-error-marker (er-mk-atom "badarg")))
+              :else n)))))))
 
 (define
   er-bif-is-function

next/.gitignore

@@ -0,0 +1 @@
+data/

next/README.md

@@ -0,0 +1,170 @@
+# next — fed-sx Milestone 1 kernel
+
+Single-instance, single-actor fed-sx server built as Erlang-on-SX modules.
+See `plans/fed-sx-design.md` for the architecture and
+`plans/fed-sx-milestone-1.md` for the build plan + per-step progress log.
+
+## Status
+
+Both Step 9 smoke proof points are functional **in-process**:
+
+- **9a-pure (verb extensibility)** — `Create{DefineActivity{Pin}}` registers Pin
+  at runtime; subsequent `Pin{path, cid}` activities fold into a pin-state
+  projection. Zero kernel code between definition and use.
+  See `next/tests/smoke_pin_pure.sh`.
+- **9b-pure (reactive application)** — A trigger projection matches Notes
+  tagged `smoketest` and derives a `TestEcho` carrying the source CID.
+  See `next/tests/smoke_app_pure.sh`.
+
+The remaining `9a-tcp` / `9b-tcp` deliverables layer TCP transport on top — see
+*Substrate gaps* below.
+
+## Layout
+
+```
+next/
+├── kernel/      Erlang-on-SX kernel modules (.erl)
+├── genesis/     SX source files for the bootstrap bundle
+├── tests/       Bash test scripts driving sx_server.exe via the epoch protocol
+└── data/        Runtime state — gitignored
+```
+
+## Module map
+
+| Module                | Role                                                                   |
+|-----------------------|------------------------------------------------------------------------|
+| `nx_cid.erl`          | Canonical CID wrapper around the host `cid:to_string` BIF              |
+| `envelope.erl`        | Activity envelope shape, canonical bytes, time-aware sig verify        |
+| `log.erl`             | Per-actor in-memory append log (open / append / tip / replay / entries) |
+| `registry.erl`        | Pure-functional + gen_server-wrapped registry keyed by Kind             |
+| `pipeline.erl`        | Validation driver + stage_envelope/signature/replay/schema             |
+| `projection.erl`      | Pure projection driver + gen_server-per-projection wrapper             |
+| `outbox.erl`          | Envelope construct + sign + publish orchestrator + broadcast            |
+| `bootstrap.erl`       | Genesis read/build/verify/load + one-call `start/3` kernel bring-up    |
+| `define_registry.erl` | Meta-projection fold for `Create{Define*}` → registry                  |
+| `sandbox.erl`         | `eval_pure/2,3` try/catch envelope for projection folds                |
+| `nx_kernel.erl`       | Long-lived runtime orchestrator; per-actor bucketed state (m2 Step 1a)  |
+| `http_server.erl`     | route/1,2 + format-aware GET + POST + Accept header content negotiation |
+
+## Genesis bundle
+
+`next/genesis/` contains 31 SX files across 7 sections, all consumed as data
+(read + serialised by `bootstrap:populate_registry`, not eval'd):
+
+- 3 activity-types — Create, Update, Delete
+- 10 object-types — SXArtifact, Note, Tombstone, 6 Define* meta-types, Snapshot
+- 7 projections — activity-log, by-type, by-actor, by-object, actor-state,
+  define-registry, audience-graph
+- 3 validators — envelope-shape, signature, type-schema
+- 3 codecs — dag-cbor, raw, dag-json
+- 2 sig-suites — rsa-sha256-2018, ed25519-2020
+- 3 audience predicates — Public, Followers, Direct
+
+`manifest.sx` is the bundle root, listed in dependency-friendly order.
+
+## Tests
+
+43 test suites, ~560+ assertions. Each script drives `sx_server.exe` via the
+epoch protocol — loads the Erlang substrate, loads relevant kernel modules
+via `code:load_binary` / `erlang-load-module`, then exercises behaviour
+through `erlang-eval-ast`.
+
+Conventions:
+
+- Scripts marked `_pure.sh` exercise pure-functional state.
+- Scripts marked `_server.sh` (or no suffix) exercise gen_server APIs and
+  must inline `start_link` with operations — the Erlang-on-SX scheduler
+  doesn't preserve spawned processes across separate `erlang-eval-ast`
+  invocations.
+- `smoke_*_pure.sh` are end-to-end smoke tests demonstrating the §Step 9
+  proof points without TCP / curl / JSON.
+
+The Erlang-on-SX conformance gate (`bash lib/erlang/conformance.sh`, **729 /
+729**) is the no-regression contract — every commit on `loops/fed-sx-m1`
+preserves it.
+
+## Substrate
+
+Each `.erl` source file is hot-loaded at boot via
+`code:load_binary(Mod, Filename, SourceString)` (Phase 7 BIF). Tests drive
+the runtime via the epoch protocol:
+
+```bash
+printf '(epoch 1)\n(load "lib/erlang/runtime.sx")\n(epoch 2)\n<test-expr>\n' \
+  | hosts/ocaml/_build/default/bin/sx_server.exe
+```
+
+The kernel calls into these host primitives: `crypto:hash/2`,
+`cid:from_bytes/1`, `cid:to_string/1`, `file:read_file/1`, `file:write_file/2`,
+`file:delete/1`, `file:list_dir/1`, `code:load_binary/3`, plus `http:listen/2`
+(the briefing's allowed scope exception, added to `lib/erlang/runtime.sx`).
+
+### Substrate gaps (parked work)
+
+These three gaps block the remaining unchecked deliverables:
+
+1. **Term codec** (`3b`/`3c`) — **all three substrate fixes done 2026-06-05:**
+   `erlang:binary_to_list/1` and `erlang:list_to_binary/1` registered in
+   `lib/erlang/runtime.sx` (iolist-aware); the tokenizer's `$X` branch
+   emits the decimal char code; `atom_to_list/1` and `integer_to_list/1`
+   now return Erlang charlists (standard Erlang semantics) with `list_to_atom`/
+   `list_to_integer` accepting both charlists and SX strings for back-compat.
+   759/759 conformance. The full term-codec primitive set is in place —
+   Step 3b on-disk segment writer can encode arbitrary Erlang activity
+   terms (atoms, ints, binaries, tuples, lists) into byte sequences using
+   only Erlang-native primitives.
+
+2. **SX-source eval bridge** — There's no BIF that lets Erlang call into the
+   SX evaluator on a parsed source string. Blocks evaluating the `:schema` /
+   `:fold` / `:predicate` / `:verify` bodies from the genesis bundle. Erlang-fun
+   stand-ins (`pipeline:stage_schema`, `define_registry:fold`, etc.) prove the
+   API shapes; the bridge would let bundle bodies dispatch through them
+   unchanged.
+
+3. **Dict ↔ proplist marshalling for `http:listen/2`** — **done 2026-06-05.**
+   `er-bif-http-listen` marshals the native server's request dict
+   (`{:method :path :query :headers :body}`) into the proplist shape
+   `[{method, Bin}, {path, Bin}, {query, Bin}, {headers, [{Name, Value}]},
+   {body, Bin}]` that `http_server:route/2` consumes, and converts the
+   handler's response proplist back to `{:status :headers :body}` for the
+   native server to serialise. Helpers (`er-request-dict-to-proplist`,
+   `er-proplist-to-dict`, `er-of-sx-deep`, `er-to-sx-deep`,
+   `er-dict-to-header-proplist`, `er-proplist-fill!`) live alongside the
+   BIF wrapper in `lib/erlang/runtime.sx`. The BIF also spawns the handler
+   into a real Erlang process via `er-spawn-fun` + `er-sched-run-all!`
+   so `self()` / `gen_server:call` work inside route handlers (the kernel
+   and projection gen_servers reach the handler this way). Verified by
+   `next/tests/http_marshal.sh` and the live TCP smoke
+   `next/tests/http_server_tcp.sh` / `http_server_start.sh`. Unblocks
+   `Step 8b-start` (TCP listener spawn) and the curl-driven 9a-tcp / 9b-tcp
+   smoke tests.
+
+### Bringing up the kernel
+
+For tests, `bootstrap:start/3(ActorId, KeySpec, ActorState)` is the
+one-call boot:
+
+```erlang
+KM = <<1,2,3,4>>,
+KS = [{key_id, k1}, {algorithm, ed25519}, {value, KM}],
+AS = [{public_keys, [[{id, k1}, {created, 0}, {value, KM}]]}],
+Pid = bootstrap:start(alice, KS, AS),
+%% nx_kernel + registry populated; you now have a kernel.
+```
+
+The HTTP layer (`http_server`) and `nx_kernel:publish/1` flow through the
+same in-process gen_servers; `http_publish_fold.sh` is the end-to-end proof
+the chain works.
+
+## What's next (when work resumes)
+
+In priority order:
+
+1. **8b-start** — `http_server:start/1` spawns a process hosting `http:listen/2`.
+   (8b-bridge done — see Substrate gap #3.)
+2. **9a-tcp / 9b-tcp** — replace the in-process smoke scripts with curl-driven
+   versions hitting the running server.
+3. **Term codec / on-disk log** — needs either a new BIF or a temp-file
+   workaround; current in-memory log keeps everything functional otherwise.
+4. **SX-source eval bridge** — unlocks real `:schema` / `:fold` body
+   evaluation from the genesis bundle.

next/genesis/activity-types/announce.sx

@@ -0,0 +1,14 @@
+;; next/genesis/activity-types/announce.sx
+;;
+;; Bootstrap definition of the Announce verb per design §13.5 / m2
+;; Step 11. An Announce re-broadcasts a peer's activity to the
+;; announcer's followers: the announcer's outbox carries an Announce
+;; envelope whose :object is the original activity's CID. Followers
+;; can re-fetch the wrapped activity from the original instance if
+;; their projection wants to fold the body.
+
+(DefineActivity
+  :name "Announce"
+  :doc "Re-broadcast a peer's activity to followers. :object is the CID of the activity being announced. Recipients see the Announce in their inbox / feed; their projection decides whether to fetch the wrapped activity body."
+  :schema (fn (act) (string? (-> act :object)))
+  :semantics (fn (state act) state))

next/genesis/activity-types/create.sx

@@ -0,0 +1,15 @@
+;; next/genesis/activity-types/create.sx
+;;
+;; Bootstrap definition of the Create verb per design §3 and §12.2.
+;; Read as data by the bundler (bootstrap.erl) — never evaluated as
+;; code. The :schema and :semantics bodies are SX source; the
+;; validation pipeline (Step 6) and projection scheduler (Step 7)
+;; evaluate them at the appropriate times.
+
+(DefineActivity
+  :name "Create"
+  :doc "Publish a new object. Required for actor onboarding and for\n        every Define* meta-activity. The activity's :object holds\n        the canonical content of the published object."
+  :schema (fn
+    (act)
+    (and (not (nil? (-> act :object))) (string? (-> act :object :type))))
+  :semantics (fn (state act) state))

next/genesis/activity-types/delete.sx

@@ -0,0 +1,13 @@
+;; next/genesis/activity-types/delete.sx
+;;
+;; Bootstrap definition of the Delete verb per design §3 and §12.2.
+;; Read as data by the bundler — never evaluated as code here. The
+;; :schema and :semantics bodies are SX source; the validator
+;; pipeline (Step 6) and projection scheduler (Step 7) evaluate them
+;; at the appropriate times.
+
+(DefineActivity
+  :name "Delete"
+  :doc "Tombstone an existing object. :object is the CID of the\n        target. Projections fold Delete by removing the object from\n        their working indexes; the underlying log line is never\n        erased — durability of the historical record is independent\n        of projection state."
+  :schema (fn (act) (string? (-> act :object)))
+  :semantics (fn (state act) state))

next/genesis/activity-types/endorse.sx

@@ -0,0 +1,13 @@
+;; next/genesis/activity-types/endorse.sx
+;;
+;; Bootstrap definition of the Endorse verb per design §13.5 / m2
+;; Step 11. An Endorse expresses cross-actor signal on a target
+;; activity (like / share / etc.). :object is the target activity's
+;; CID; :kind is the endorsement variant (string). Projections
+;; aggregate endorsements into counters / heat / ranking signals.
+
+(DefineActivity
+  :name "Endorse"
+  :doc "Cross-actor signal on a target activity. :object is the target activity's CID; :kind is the endorsement variant (e.g. 'like', 'share'). Projections aggregate endorsements into counters / heat / ranking signals."
+  :schema (fn (act) (and (string? (-> act :object)) (string? (-> act :kind))))
+  :semantics (fn (state act) state))

next/genesis/activity-types/update.sx

@@ -0,0 +1,15 @@
+;; next/genesis/activity-types/update.sx
+;;
+;; Bootstrap definition of the Update verb per design §3 and §12.2.
+;; Read as data by the bundler — never evaluated as code here. The
+;; :schema and :semantics bodies are SX source; the validator
+;; pipeline (Step 6) and projection scheduler (Step 7) evaluate them
+;; at the appropriate times.
+
+(DefineActivity
+  :name "Update"
+  :doc "Patch or replace an existing object. :object is the CID of\n        the target; :patch is the field-level edit. Behaviour is\n        delegated to per-object-type semantics — e.g. an Update of a\n        DefineActivity supersedes the prior registry entry; an\n        Update of a Person actor rotates keys via :patch :add-publicKey\n        + :patch :supersede."
+  :schema (fn
+    (act)
+    (and (string? (-> act :object)) (not (nil? (-> act :patch)))))
+  :semantics (fn (state act) state))

next/genesis/audience/direct.sx

@@ -0,0 +1,14 @@
+;; next/genesis/audience/direct.sx
+;;
+;; Direct audience: an actor is a member iff they are
+;; explicitly named in the activity's :to or :cc lists. No
+;; group expansion — true direct addressing only.
+
+(DefineAudience
+  :name "Direct"
+  :doc "Direct-addressing predicate. Tests literal membership\n        in the activity's :to or :cc."
+  :member-of (fn
+    (actor audience)
+    (or
+      (member? actor (-> audience :to))
+      (member? actor (-> audience :cc)))))

next/genesis/audience/followers.sx

@@ -0,0 +1,14 @@
+;; next/genesis/audience/followers.sx
+;;
+;; Followers audience: an actor is a member iff they appear in
+;; the audience-owner's :followers set in the audience-graph
+;; projection. Federation (m2) wires this to peer delivery.
+
+(DefineAudience
+  :name "Followers"
+  :doc "Followers-of-owner predicate. Looks up the\n        audience-graph projection's :followers list for the\n        audience owner and tests membership."
+  :member-of (fn
+    (actor audience)
+    (member?
+      actor
+      (-> (get-projection :audience-graph) (-> audience :owner) :followers))))

next/genesis/audience/public.sx

@@ -0,0 +1,9 @@
+;; next/genesis/audience/public.sx
+;;
+;; Public audience: every actor is a member. Maps to the AP
+;; magic id `https://www.w3.org/ns/activitystreams#Public`.
+
+(DefineAudience
+  :name "Public"
+  :doc "Public audience predicate. Always returns true — every\n        actor on the network is considered a member."
+  :member-of (fn (actor audience) true))

next/genesis/codecs/dag-cbor.sx

@@ -0,0 +1,13 @@
+;; next/genesis/codecs/dag-cbor.sx
+;;
+;; Canonical CBOR encoding per IPLD dag-cbor. Used to compute
+;; envelope canonical bytes for signature coverage and to serialise
+;; the genesis bundle itself. In Erlang-on-SX mode the kernel
+;; dispatches to the host cid:to_string substrate (Step 1b) when
+;; this codec is requested.
+
+(DefineCodec
+  :name "dag-cbor"
+  :doc "Deterministic CBOR with dag-cbor restrictions: sorted\n        map keys, no floats unless required, no indefinite-length\n        items. The canonical wire format for fed-sx artifacts."
+  :encode (fn (term) (host-codec :dag-cbor :encode term))
+  :decode (fn (bytes) (host-codec :dag-cbor :decode bytes)))

next/genesis/codecs/dag-json.sx

@@ -0,0 +1,12 @@
+;; next/genesis/codecs/dag-json.sx
+;;
+;; JSON encoding with dag-json restrictions per IPLD: sorted map
+;; keys, no NaN / Infinity, no comments, CIDs as `{"/": "..."}`.
+;; Used as the human-readable wire format for ActivityPub interop
+;; (JSON-LD over dag-json).
+
+(DefineCodec
+  :name "dag-json"
+  :doc "Deterministic JSON with dag-json restrictions. Sorted\n        keys, CIDs as the {\"/\": \"...\"} object. Used by the\n        HTTP server (Step 8) for application/json responses."
+  :encode (fn (term) (host-codec :dag-json :encode term))
+  :decode (fn (bytes) (host-codec :dag-json :decode bytes)))

next/genesis/codecs/raw.sx

@@ -0,0 +1,12 @@
+;; next/genesis/codecs/raw.sx
+;;
+;; Identity codec — input bytes pass through unchanged in both
+;; directions. Used for already-encoded payloads and for binary
+;; artifacts (images, archives) whose CID is computed over the
+;; raw bytes directly.
+
+(DefineCodec
+  :name "raw"
+  :doc "Identity codec. The CID's multicodec byte is 0x55.\n        :encode and :decode return their input unchanged."
+  :encode (fn (bytes) bytes)
+  :decode (fn (bytes) bytes))

next/genesis/manifest.sx

@@ -0,0 +1,51 @@
+;; next/genesis/manifest.sx
+;;
+;; Genesis bundle root per design §12.2. Lists every definition file
+;; that gets packed into the bundle. The bundler (bootstrap.erl)
+;; walks this manifest, reads each referenced file, parses its
+;; top-level form, and inserts it into the bundle dict at the
+;; appropriate section path.
+;;
+;; The bundle CID is the content-address of the resulting dag-cbor
+;; (or v1 stand-in) blob over the assembled dict. That CID is
+;; baked into the kernel at build time and re-verified on startup
+;; per design §12.3.
+;;
+;; Section values are bare parenthesised paths (data lists, not
+;; function calls) — the manifest is consumed by `parse`, not
+;; `eval`. Empty sections are written as `()`.
+
+(GenesisManifest
+  :version "0.0.1"
+  :kernel-version "1.0.0-m1"
+  :activity-types ("activity-types/create.sx"
+    "activity-types/update.sx"
+    "activity-types/delete.sx"
+    "activity-types/announce.sx"
+    "activity-types/endorse.sx")
+  :object-types ("object-types/sx-artifact.sx"
+    "object-types/note.sx"
+    "object-types/tombstone.sx"
+    "object-types/person.sx"
+    "object-types/service.sx"
+    "object-types/group.sx"
+    "object-types/define-activity.sx"
+    "object-types/define-object.sx"
+    "object-types/define-projection.sx"
+    "object-types/define-validator.sx"
+    "object-types/define-codec.sx"
+    "object-types/define-sig-suite.sx"
+    "object-types/snapshot.sx")
+  :projections ("projections/activity-log.sx"
+    "projections/by-type.sx"
+    "projections/by-actor.sx"
+    "projections/by-object.sx"
+    "projections/actor-state.sx"
+    "projections/define-registry.sx"
+    "projections/audience-graph.sx")
+  :validators ("validators/envelope-shape.sx"
+    "validators/signature.sx"
+    "validators/type-schema.sx")
+  :codecs ("codecs/dag-cbor.sx" "codecs/raw.sx" "codecs/dag-json.sx")
+  :sig-suites ("sig-suites/rsa-sha256-2018.sx" "sig-suites/ed25519-2020.sx")
+  :audience ("audience/public.sx" "audience/followers.sx" "audience/direct.sx"))

next/genesis/object-types/define-activity.sx

@@ -0,0 +1,12 @@
+;; next/genesis/object-types/define-activity.sx
+;;
+;; Meta-object that registers a new activity verb. Published as
+;; Create{DefineActivity{...}}; the define-registry projection
+;; folds it into the activity-types registry. Per design §5.
+
+(DefineObject
+  :name "DefineActivity"
+  :doc "Activity-type registration. :name is the verb (e.g.\n        \"Pin\"); :schema is an SX predicate over activity\n        envelopes; :semantics is an optional state-fold body."
+  :schema (fn
+    (obj)
+    (and (string? (-> obj :name)) (not (nil? (-> obj :schema))))))

next/genesis/object-types/define-codec.sx

@@ -0,0 +1,15 @@
+;; next/genesis/object-types/define-codec.sx
+;;
+;; Meta-object that registers a content codec — an encode/decode
+;; pair. The bootstrap bundle ships dag-cbor, raw, and dag-json
+;; codecs; new codecs can be added via Create{DefineCodec{...}}.
+
+(DefineObject
+  :name "DefineCodec"
+  :doc "Codec registration. :name identifies the codec ('dag-cbor',\n        'raw', 'dag-json', ...); :encode and :decode are the\n        SX bodies the kernel calls when serialising / parsing\n        artifacts under this codec."
+  :schema (fn
+    (obj)
+    (and
+      (string? (-> obj :name))
+      (not (nil? (-> obj :encode)))
+      (not (nil? (-> obj :decode))))))

next/genesis/object-types/define-object.sx

@@ -0,0 +1,12 @@
+;; next/genesis/object-types/define-object.sx
+;;
+;; Meta-object that registers a new object-type. Bootstrap-level —
+;; runtime registration of new object types (e.g. DefineSubscription
+;; in the Step 9b smoke test) flows through this.
+
+(DefineObject
+  :name "DefineObject"
+  :doc "Object-type registration. :name is the type tag (e.g.\n        \"PinSpec\"); :schema is an SX predicate over object\n        forms of that type."
+  :schema (fn
+    (obj)
+    (and (string? (-> obj :name)) (not (nil? (-> obj :schema))))))

next/genesis/object-types/define-projection.sx

@@ -0,0 +1,16 @@
+;; next/genesis/object-types/define-projection.sx
+;;
+;; Meta-object that registers a new projection. The projection
+;; scheduler (Step 7) spawns one gen_server per registered
+;; projection and feeds activities through its :fold body in
+;; sandbox mode.
+
+(DefineObject
+  :name "DefineProjection"
+  :doc "Projection registration. :name is the projection key;\n        :initial-state is the empty state value; :fold is the\n        pure (state activity) -> state function evaluated in\n        sandbox mode per activity."
+  :schema (fn
+    (obj)
+    (and
+      (string? (-> obj :name))
+      (not (nil? (-> obj :initial-state)))
+      (not (nil? (-> obj :fold))))))

next/genesis/object-types/define-sig-suite.sx

@@ -0,0 +1,12 @@
+;; next/genesis/object-types/define-sig-suite.sx
+;;
+;; Meta-object that registers a signature suite. Bootstrap ships
+;; rsa-sha256-2018 and ed25519-2020; the suite name maps an
+;; algorithm to a :verify body and a :key-format predicate.
+
+(DefineObject
+  :name "DefineSigSuite"
+  :doc "Signature suite registration. :name identifies the suite\n        ('rsa-sha256-2018', 'ed25519-2020', ...); :verify is the\n        SX (canonical-bytes signature key) -> bool body; the\n        envelope-signature validator dispatches by suite name."
+  :schema (fn
+    (obj)
+    (and (string? (-> obj :name)) (not (nil? (-> obj :verify))))))

next/genesis/object-types/define-validator.sx

@@ -0,0 +1,12 @@
+;; next/genesis/object-types/define-validator.sx
+;;
+;; Meta-object that registers a validator predicate. The validation
+;; pipeline (Step 6) consults registered validators by name when
+;; running its stages.
+
+(DefineObject
+  :name "DefineValidator"
+  :doc "Validator registration. :name is the validator key (e.g.\n        \"envelope-shape\"); :predicate is the SX (activity) ->\n        ok|{error, R} body."
+  :schema (fn
+    (obj)
+    (and (string? (-> obj :name)) (not (nil? (-> obj :predicate))))))

next/genesis/object-types/group.sx

@@ -0,0 +1,11 @@
+;; next/genesis/object-types/group.sx
+;;
+;; Per design §9.1: a Group is a multi-controller actor — typically
+;; a working group, channel, or collective whose membership is
+;; managed via Add/Remove activities. Sig-suite validation honours
+;; the current key-set rather than a single keypair.
+
+(DefineObject
+  :name "Group"
+  :doc "Multi-controller actor. :name is the group's display name; :preferredUsername is the local handle; :summary is the description; :icon is a CID or URL; :members is the current member list (managed via Add/Remove)."
+  :schema (fn (obj) (string? (-> obj :name))))

next/genesis/object-types/note.sx

@@ -0,0 +1,10 @@
+;; next/genesis/object-types/note.sx
+;;
+;; Short message intended for an audience, ActivityPub-Note-compatible.
+;; Used by the Step 9b reactive smoke test (Note tagged "smoketest"
+;; matches the Topic subscription).
+
+(DefineObject
+  :name "Note"
+  :doc "Short authored message. :content is the body text;\n        :tags is a list of subscription-routable tags."
+  :schema (fn (obj) (string? (-> obj :content))))

next/genesis/object-types/person.sx

@@ -0,0 +1,11 @@
+;; next/genesis/object-types/person.sx
+;;
+;; Per design §9.1: a Person is the canonical actor type for a
+;; human-controlled identity. Bootstrapped via Create{Person{...}}
+;; as the actor's first activity (see nx_kernel:bootstrap_actor/4).
+;; ActivityPub-Person-compatible.
+
+(DefineObject
+  :name "Person"
+  :doc "Human-controlled actor. :name is the display name; :preferredUsername is the local handle; :summary is the profile bio; :icon is a CID or URL."
+  :schema (fn (obj) (string? (-> obj :name))))

next/genesis/object-types/service.sx

@@ -0,0 +1,11 @@
+;; next/genesis/object-types/service.sx
+;;
+;; Per design §9.1: a Service is a non-human actor — a bot, an
+;; automated feed, an organisational publisher. Same activity
+;; surface as Person, different ActivityPub Actor type. Tooling
+;; treats a Service identically to a Person except for UX hints.
+
+(DefineObject
+  :name "Service"
+  :doc "Automated / programmatic actor. :name is the display name; :preferredUsername is the local handle; :summary is the profile bio; :icon is a CID or URL."
+  :schema (fn (obj) (string? (-> obj :name))))

next/genesis/object-types/snapshot.sx

@@ -0,0 +1,13 @@
+;; next/genesis/object-types/snapshot.sx
+;;
+;; Projection state checkpoint. The projection scheduler emits
+;; Snapshot{projection-name, state-cid, log-seq} periodically;
+;; cold starts read the most recent Snapshot and replay only
+;; activities after :log-seq. Per design §10.5.
+
+(DefineObject
+  :name "Snapshot"
+  :doc "Projection-state checkpoint. :projection-name identifies\n        the projection; :state-cid is the content-address of\n        the snapshotted state value; :log-seq is the activity\n        sequence number the snapshot was taken at."
+  :schema (fn
+    (obj)
+    (and (string? (-> obj :projection-name)) (string? (-> obj :state-cid)))))

next/genesis/object-types/sx-artifact.sx

@@ -0,0 +1,10 @@
+;; next/genesis/object-types/sx-artifact.sx
+;;
+;; Content-addressed SX source — a library, component, or
+;; executable form published via Create{SXArtifact{...}}.
+;; Consumers reference an artifact by its CID. Per design §3.4.
+
+(DefineObject
+  :name "SXArtifact"
+  :doc "Published SX source. :source carries the form text;\n        :language is optional ('sx' by default); :imports lists\n        CIDs the artifact depends on."
+  :schema (fn (obj) (string? (-> obj :source))))

next/genesis/object-types/tombstone.sx

@@ -0,0 +1,9 @@
+;; next/genesis/object-types/tombstone.sx
+;;
+;; Replacement for an object that has been Delete'd. Lets projection
+;; folds keep a marker without retaining the deleted content.
+
+(DefineObject
+  :name "Tombstone"
+  :doc "Marker for a deleted object. :former-cid carries the CID\n        of the object that was removed. Projections fold Tombstone\n        by replacing the cached entry (not by omitting it)."
+  :schema (fn (obj) (string? (-> obj :former-cid))))

next/genesis/projections/activity-log.sx

@@ -0,0 +1,11 @@
+;; next/genesis/projections/activity-log.sx
+;;
+;; Identity projection: stores every activity by its CID. The
+;; base ledger every other projection could be re-derived from
+;; if needed. Per design §10.2.
+
+(DefineProjection
+  :name "activity-log"
+  :doc "Maps activity CID to the full envelope. Every activity\n        flows through; no filter. State is the CID-keyed dict."
+  :initial-state {}
+  :fold (fn (state act) (assoc state (-> act :cid) act)))

next/genesis/projections/actor-state.sx

@@ -0,0 +1,26 @@
+;; next/genesis/projections/actor-state.sx
+;;
+;; Per-actor live state: publicKeys (with history per design §9.6),
+;; profile fields (preferredUsername, summary, ...), follower/
+;; following counts. Powers the actor doc endpoint and the
+;; time-aware signature verification in envelope:verify_signature/2.
+
+(DefineProjection
+  :name "actor-state"
+  :doc "Actor-id -> {publicKeys, profile, followers, following}.\n        Updated by Create{Person|Service|Group}, Update (key\n        rotation, profile edits), Move (federation migration)."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((aid (-> act :actor)) (t (-> act :type)))
+      (cond
+        (= t "Create")
+        (assoc state aid (or (-> act :object) {}))
+        (= t "Update")
+        (assoc
+          state
+          aid
+          (merge
+            (or (get state aid) {})
+            (or (-> act :patch) {})))
+        :else state))))

next/genesis/projections/audience-graph.sx

@@ -0,0 +1,25 @@
+;; next/genesis/projections/audience-graph.sx
+;;
+;; Per-actor follow / follower graph and audience caches. Folded
+;; from Follow / Accept / Reject / Undo{Follow}. Used by the
+;; activity router to expand :to / :cc audiences (Public,
+;; Followers, Direct) into concrete recipient sets. Per design §16.
+
+(DefineProjection
+  :name "audience-graph"
+  :doc "Actor-id -> {following, followers, pending} sets.\n        Updated by Follow / Accept / Reject / Undo. Federation\n        (m2) wires this projection to the delivery queue."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((t (-> act :type)))
+      (cond
+        (= t "Follow")
+        state
+        (= t "Accept")
+        state
+        (= t "Reject")
+        state
+        (= t "Undo")
+        state
+        :else state))))

next/genesis/projections/by-actor.sx

@@ -0,0 +1,15 @@
+;; next/genesis/projections/by-actor.sx
+;;
+;; Index of activity CIDs grouped by :actor. Maps actor-id to a
+;; list of CIDs in append order. Powers the per-actor outbox
+;; listing (Step 8) without re-scanning the full log.
+
+(DefineProjection
+  :name "by-actor"
+  :doc "Actor-id -> list of activity CIDs (append order)."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((a (-> act :actor)) (cid (-> act :cid)))
+      (assoc state a (append (or (get state a) (list)) (list cid))))))

next/genesis/projections/by-object.sx

@@ -0,0 +1,22 @@
+;; next/genesis/projections/by-object.sx
+;;
+;; Index of activities that reference each :object CID. Maps
+;; object-CID to the list of activity CIDs that target it
+;; (Update / Delete / Announce / etc.). Used for "show me
+;; everything that happened to X" queries.
+
+(DefineProjection
+  :name "by-object"
+  :doc "Object CID -> list of activity CIDs that target it."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((obj-cid (-> act :object)) (cid (-> act :cid)))
+      (if
+        (string? obj-cid)
+        (assoc
+          state
+          obj-cid
+          (append (or (get state obj-cid) (list)) (list cid)))
+        state))))

next/genesis/projections/by-type.sx

@@ -0,0 +1,15 @@
+;; next/genesis/projections/by-type.sx
+;;
+;; Index of activity CIDs grouped by :type. Maps type-name to a
+;; list of CIDs in append order. Used by the outbox listing
+;; endpoints (Step 8) for type-filtered pagination.
+
+(DefineProjection
+  :name "by-type"
+  :doc "Type-name -> list of activity CIDs (append order)."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((t (-> act :type)) (cid (-> act :cid)))
+      (assoc state t (append (or (get state t) (list)) (list cid))))))

next/genesis/projections/define-registry.sx

@@ -0,0 +1,33 @@
+;; next/genesis/projections/define-registry.sx
+;;
+;; The meta-projection: folds Create{Define*{...}} activities into
+;; the kernel registry. Resolves the chicken-and-egg circle —
+;; bootstrap.erl populates the registry directly at startup from
+;; the genesis bundle, and from then on define-registry's fold
+;; keeps it current as new Define* activities arrive. Per design §5.
+
+(DefineProjection
+  :name "define-registry"
+  :doc "Maps {kind, name} -> definition entry. Folded from\n        Create{DefineActivity|DefineObject|DefineProjection|\n        DefineValidator|DefineCodec|DefineSigSuite|...}. Kind is\n        derived from the inner :object :type tag."
+  :initial-state {}
+  :fold (fn
+    (state act)
+    (let
+      ((obj (-> act :object)) (otype (-> act :object :type)))
+      (cond
+        (= (-> act :type) "Create")
+        (cond
+          (= otype "DefineActivity")
+          (assoc-in state (list :activity-types (-> obj :name)) obj)
+          (= otype "DefineObject")
+          (assoc-in state (list :object-types (-> obj :name)) obj)
+          (= otype "DefineProjection")
+          (assoc-in state (list :projections (-> obj :name)) obj)
+          (= otype "DefineValidator")
+          (assoc-in state (list :validators (-> obj :name)) obj)
+          (= otype "DefineCodec")
+          (assoc-in state (list :codecs (-> obj :name)) obj)
+          (= otype "DefineSigSuite")
+          (assoc-in state (list :sig-suites (-> obj :name)) obj)
+          :else state)
+        :else state))))

next/genesis/sig-suites/ed25519-2020.sx

@@ -0,0 +1,11 @@
+;; next/genesis/sig-suites/ed25519-2020.sx
+;;
+;; W3C Verifiable Credential signature suite — Ed25519 over
+;; canonical bytes, key material in multibase. Default suite
+;; for fed-sx actors per design §9.
+
+(DefineSigSuite
+  :name "ed25519-2020"
+  :doc "Ed25519 verification. Key carries publicKeyMultibase.\n        :verify takes canonical-bytes + signature + key and\n        returns bool. Real verification deferred to m2 once\n        crypto:verify_ed25519/3 BIF lands; v1 stand-in returns\n        false to defer all Ed25519-signed activities."
+  :verify (fn (canonical-bytes signature key) false)
+  :key-format (fn (key-doc) (string? (-> key-doc :publicKeyMultibase))))

next/genesis/sig-suites/rsa-sha256-2018.sx

@@ -0,0 +1,11 @@
+;; next/genesis/sig-suites/rsa-sha256-2018.sx
+;;
+;; W3C Verifiable Credential signature suite — RSA-SHA256 over
+;; canonical bytes, key material in PEM. Compatible with
+;; Mastodon's HTTP-Signatures / Linked-Data-Signatures-2017.
+
+(DefineSigSuite
+  :name "rsa-sha256-2018"
+  :doc "RSA-SHA256 verification. Key carries publicKeyPem.\n        :verify takes canonical-bytes + signature + key and\n        returns bool. Real verification deferred to m2 once\n        crypto:verify_rsa/3 BIF lands; v1 stand-in returns\n        false to defer all RSA-signed activities."
+  :verify (fn (canonical-bytes signature key) false)
+  :key-format (fn (key-doc) (string? (-> key-doc :publicKeyPem))))

next/genesis/validators/envelope-shape.sx

@@ -0,0 +1,22 @@
+;; next/genesis/validators/envelope-shape.sx
+;;
+;; Validates required envelope fields per design §3.1. Stage 1 of
+;; the validation pipeline (Step 6). Mirrors the kernel's
+;; envelope:validate_shape/1 from Step 2a — when the pipeline runs
+;; in OCaml-side sandbox eval mode it dispatches by name; when it
+;; runs through the kernel Erlang path it short-circuits to the BIF.
+
+(DefineValidator
+  :name "envelope-shape"
+  :doc "Required-fields check on the activity envelope:\n        :id, :type, :actor, :published, :signature must all be\n        present and non-nil. The :signature sub-field needs\n        :key_id, :algorithm, :value."
+  :predicate (fn
+    (act)
+    (and
+      (not (nil? (-> act :id)))
+      (not (nil? (-> act :type)))
+      (not (nil? (-> act :actor)))
+      (not (nil? (-> act :published)))
+      (not (nil? (-> act :signature)))
+      (not (nil? (-> act :signature :key_id)))
+      (not (nil? (-> act :signature :algorithm)))
+      (not (nil? (-> act :signature :value))))))

next/genesis/validators/signature.sx

@@ -0,0 +1,13 @@
+;; next/genesis/validators/signature.sx
+;;
+;; Stage 2 of the validation pipeline per design §14. Verifies the
+;; activity signature against the time-relevant public key in the
+;; actor-state projection. Bootstrap entry; the kernel dispatches
+;; to envelope:verify_signature/2 (Step 2c) when running in
+;; Erlang-on-SX mode. Per design §9.6 the lookup is timestamp-aware
+;; — key validity is evaluated at :published, not "now".
+
+(DefineValidator
+  :name "signature"
+  :doc "Signature verification. Picks the signature suite by\n        :signature :algorithm, fetches the key with id ==\n        :signature :key_id that was active at :published from\n        the actor-state projection, then dispatches to the\n        suite's :verify body."
+  :predicate (fn (act) true))

next/genesis/validators/type-schema.sx

@@ -0,0 +1,21 @@
+;; next/genesis/validators/type-schema.sx
+;;
+;; Stage 5 of the validation pipeline per design §14. Validates
+;; the activity's :object against the schema registered for its
+;; :object :type in the define-registry projection.
+
+(DefineValidator
+  :name "type-schema"
+  :doc "Looks up the object-type registration in the\n        define-registry projection, fetches its :schema body,\n        and evaluates it against (-> act :object). Returns true\n        when no object-type is named (some verbs carry no\n        :object) or when no schema is registered for the named\n        type (open-world default — Step 6 may tighten)."
+  :predicate (fn
+    (act)
+    (let
+      ((obj (-> act :object)))
+      (cond
+        (nil? obj)
+        true
+        (nil? (-> obj :type))
+        true
+        :else (let
+          ((schema (-> (registry-lookup :object-types (-> obj :type)) :schema)))
+          (if (nil? schema) true (apply-schema schema obj)))))))

next/kernel/actor_state.erl

@@ -0,0 +1,260 @@
+-module(actor_state).
+-export([fold/2, fold_fn/0, new/0, lookup/2, has/2, actors/1,
+         profile_type/1, profile_name/1, profile_field/2,
+         key_history/1, active_keys_at/2, find_key_by_id/2]).
+
+%% Actor-state projection fold — Erlang-fun stand-in for the
+%% genesis `actor-state.sx` projection body. Tracks per-actor
+%% profiles, key-history, and Move pointers per design §9.1-§9.4.
+%%
+%% State shape:
+%%   [{ActorId, Profile}, ...]
+%%
+%% Profile = [{type, person|service|group},
+%%            {name, Bin},
+%%            {preferredUsername, Bin},
+%%            {summary, Bin},
+%%            {icon, Bin},
+%%            {public_keys, [Key]},
+%%            {moved_to, ActorIdOrUrl},
+%%            {created, N}]
+%%
+%% Bridge note: the SX-source eval bridge would replace this fold
+%% body once available (same gap as Step 5d-pure / Step 6c-schema-pure).
+%% define_registry.erl is the structural twin.
+%%
+%% lists:keyfind/keymember aren't in this substrate (Step 1a noted
+%% same gap), so local `find_keyed`/`has_keyed`/`set_keyed` helpers
+%% handle the keyed-list ops.
+
+new() -> [].
+
+actors(State) -> [Id || {Id, _Profile} <- State].
+
+has(ActorId, State) -> has_keyed(ActorId, State).
+
+lookup(ActorId, State) ->
+    case find_keyed(ActorId, State) of
+        {ok, Profile}   -> {ok, Profile};
+        {error, _}      -> not_found
+    end.
+
+%% ── Fold dispatch ───────────────────────────────────────────────
+
+fold(Activity, State) ->
+    case envelope:get_field(type, Activity) of
+        {ok, create}    -> fold_create(Activity, State);
+        {ok, update}    -> fold_update(Activity, State);
+        {ok, move}      -> fold_move(Activity, State);
+        _               -> State
+    end.
+
+fold_create(Activity, State) ->
+    case envelope:get_field(object, Activity) of
+        {ok, Obj} ->
+            case envelope:get_field(type, Obj) of
+                {ok, ObjType} ->
+                    case is_actor_type(ObjType) of
+                        true  -> register_actor(Activity, Obj, ObjType, State);
+                        false -> State
+                    end;
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+register_actor(Activity, Obj, ObjType, State) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, ActorId} ->
+            case has_keyed(ActorId, State) of
+                true ->
+                    State;
+                false ->
+                    Created = published_seq(Activity),
+                    Profile = build_profile(ObjType, Obj, Created),
+                    State ++ [{ActorId, Profile}]
+            end;
+        _ -> State
+    end.
+
+fold_update(Activity, State) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, ActorId} ->
+            case find_keyed(ActorId, State) of
+                {ok, Profile} ->
+                    case envelope:get_field(patch, Activity) of
+                        {ok, Patch} ->
+                            Published = published_seq(Activity),
+                            NewProfile = apply_patch(Profile, Patch, Published),
+                            set_keyed(ActorId, NewProfile, State);
+                        _ -> State
+                    end;
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+fold_move(Activity, State) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, ActorId} ->
+            case find_keyed(ActorId, State) of
+                {ok, Profile} ->
+                    case envelope:get_field(moved_to, Activity) of
+                        {ok, Target} ->
+                            NewProfile = set_keyed(moved_to, Target, Profile),
+                            set_keyed(ActorId, NewProfile, State);
+                        _ -> State
+                    end;
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+%% ── Profile assembly ────────────────────────────────────────────
+
+build_profile(ObjType, Obj, Created) ->
+    Base = [{type, ObjType}, {created, Created}],
+    Fields = [name, preferredUsername, summary, icon, public_keys],
+    Base ++ collect_fields(Fields, Obj).
+
+collect_fields([], _) -> [];
+collect_fields([F | Rest], Obj) ->
+    case envelope:get_field(F, Obj) of
+        {ok, V}     -> [{F, V} | collect_fields(Rest, Obj)];
+        _           -> collect_fields(Rest, Obj)
+    end.
+
+merge_patch(Profile, []) -> Profile;
+merge_patch(Profile, [{K, V} | Rest]) ->
+    merge_patch(set_keyed(K, V, Profile), Rest);
+merge_patch(Profile, _) -> Profile.
+
+%% apply_patch/3 — same as merge_patch but special-cases two
+%% key-rotation patch entries per design §9.6:
+%%   {add_publicKey, KeyProplist}   — append a new key to :public_keys,
+%%                                    defaulting :created to Published.
+%%   {supersede, OldKeyId}          — mark the key with :id =:= OldKeyId
+%%                                    as :superseded_at = Published.
+%% Other patch entries fall through to last-write-wins per key.
+
+apply_patch(Profile, [], _Published) -> Profile;
+apply_patch(Profile, [{add_publicKey, NewKey} | Rest], Published) ->
+    Augmented = ensure_created(NewKey, Published),
+    Current = current_public_keys(Profile),
+    NewKeys = Current ++ [Augmented],
+    apply_patch(set_keyed(public_keys, NewKeys, Profile), Rest, Published);
+apply_patch(Profile, [{supersede, OldKeyId} | Rest], Published) ->
+    Current = current_public_keys(Profile),
+    NewKeys = mark_superseded(OldKeyId, Published, Current),
+    apply_patch(set_keyed(public_keys, NewKeys, Profile), Rest, Published);
+apply_patch(Profile, [{K, V} | Rest], Published) ->
+    apply_patch(set_keyed(K, V, Profile), Rest, Published);
+apply_patch(Profile, _, _) -> Profile.
+
+current_public_keys(Profile) ->
+    case find_keyed(public_keys, Profile) of
+        {ok, Keys} -> Keys;
+        _          -> []
+    end.
+
+ensure_created(Key, Published) ->
+    case find_keyed(created, Key) of
+        {ok, _} -> Key;
+        _       -> set_keyed(created, Published, Key)
+    end.
+
+mark_superseded(_, _, []) -> [];
+mark_superseded(OldId, At, [Key | Rest]) ->
+    case find_keyed(id, Key) of
+        {ok, OldId} ->
+            case find_keyed(superseded_at, Key) of
+                {ok, _} -> [Key | mark_superseded(OldId, At, Rest)];
+                _       -> [set_keyed(superseded_at, At, Key) | mark_superseded(OldId, At, Rest)]
+            end;
+        _ -> [Key | mark_superseded(OldId, At, Rest)]
+    end.
+
+%% Key-history view — full :public_keys list including superseded
+%% entries (per §9.6: history is preserved so historical activities
+%% verify against keys that were active at their :published time).
+
+key_history(Profile) ->
+    current_public_keys(Profile).
+
+%% active_keys_at/2 — the subset of :public_keys active at Now,
+%% mirroring envelope's is_active_at semantics (local copy: envelope
+%% keeps the predicate private).
+
+active_keys_at(Profile, Now) ->
+    [K || K <- current_public_keys(Profile),
+          key_active_at(K, Now)].
+
+find_key_by_id(KeyId, Profile) ->
+    find_key_by_id_in(KeyId, current_public_keys(Profile)).
+
+find_key_by_id_in(_, []) -> not_found;
+find_key_by_id_in(WantId, [K | Rest]) ->
+    case find_keyed(id, K) of
+        {ok, WantId} -> {ok, K};
+        _            -> find_key_by_id_in(WantId, Rest)
+    end.
+
+key_active_at(Key, Now) ->
+    case find_keyed(created, Key) of
+        {ok, Created} when Now >= Created ->
+            case find_keyed(superseded_at, Key) of
+                {ok, SupAt} -> Now < SupAt;
+                _           -> true
+            end;
+        _ -> false
+    end.
+
+published_seq(Activity) ->
+    case envelope:get_field(published, Activity) of
+        {ok, P} -> P;
+        _       -> 0
+    end.
+
+is_actor_type(person)   -> true;
+is_actor_type(service)  -> true;
+is_actor_type(group)    -> true;
+is_actor_type(_)        -> false.
+
+%% ── Profile accessors ───────────────────────────────────────────
+
+profile_type(Profile) ->
+    case find_keyed(type, Profile) of
+        {ok, T} -> T;
+        _       -> nil
+    end.
+
+profile_name(Profile) ->
+    case find_keyed(name, Profile) of
+        {ok, N} -> N;
+        _       -> nil
+    end.
+
+profile_field(F, Profile) ->
+    case find_keyed(F, Profile) of
+        {ok, V} -> {ok, V};
+        _       -> not_found
+    end.
+
+%% ── Projection integration ──────────────────────────────────────
+
+fold_fn() ->
+    fun (Activity, State) -> fold(Activity, State) end.
+
+%% ── Internal ────────────────────────────────────────────────────
+
+has_keyed(_, []) -> false;
+has_keyed(K, [{K, _} | _]) -> true;
+has_keyed(K, [_ | Rest]) -> has_keyed(K, Rest).
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].

next/kernel/announce_state.erl

@@ -0,0 +1,79 @@
+-module(announce_state).
+-export([new/0, fold/2, fold_fn/0,
+         announcers_for/2, announce_count/2, announced_cids/1,
+         has_announced/3]).
+
+%% Announce-fanout projection. Folds Announce activities into a
+%% per-target-Cid set of announcer ActorIds so projections can
+%% answer "who re-broadcast this activity" / "how many announces
+%% does this Note have" / "what activities has X announced".
+%%
+%% Announce envelope shape (per next/genesis/activity-types/announce.sx):
+%%   [{type, announce},
+%%    {actor, AnnouncerActorId},
+%%    {object, TargetCidBinary},
+%%    ...]
+%%
+%% State shape:
+%%   [{TargetCid, [Announcer1, Announcer2, ...]}, ...]
+%%
+%% Set semantics — the same actor announcing the same target twice
+%% is a no-op (already in the list). Undo{Announce} retraction
+%% defers to a follow-up.
+
+new() -> [].
+
+fold_fn() ->
+    fun (Activity, State) -> fold(Activity, State) end.
+
+fold(Activity, State) ->
+    case envelope:get_field(type, Activity) of
+        {ok, announce} -> fold_announce(Activity, State);
+        _              -> State
+    end.
+
+fold_announce(Activity, State) ->
+    case {envelope:get_field(actor, Activity),
+          envelope:get_field(object, Activity)} of
+        {{ok, Actor}, {ok, Cid}} -> add_announcer(Cid, Actor, State);
+        _                        -> State
+    end.
+
+add_announcer(Cid, Actor, State) ->
+    Current = case find_keyed(Cid, State) of
+        {ok, Set} -> Set;
+        _         -> []
+    end,
+    case contains(Actor, Current) of
+        true  -> State;
+        false -> set_keyed(Cid, Current ++ [Actor], State)
+    end.
+
+%% ── Read-side accessors ───────────────────────────────────────
+
+announcers_for(Cid, State) ->
+    case find_keyed(Cid, State) of
+        {ok, Set} -> Set;
+        _         -> []
+    end.
+
+announce_count(Cid, State) -> length(announcers_for(Cid, State)).
+
+announced_cids(State) -> [C || {C, _} <- State].
+
+has_announced(Actor, Cid, State) ->
+    contains(Actor, announcers_for(Cid, State)).
+
+%% ── Internal ──────────────────────────────────────────────────
+
+contains(_, []) -> false;
+contains(X, [X | _]) -> true;
+contains(X, [_ | Rest]) -> contains(X, Rest).
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].

next/kernel/backfill.erl

@@ -0,0 +1,136 @@
+-module(backfill).
+-export([slice/2, slice/3,
+         wrap_backfill/1, parse_mode/1,
+         all_entries/1, last_n_entries/2, last_t_entries/3,
+         since_cid_entries/2, none_entries/0]).
+
+%% Backfill mode slicing per design §13.3 / Step 9. When A follows B
+%% with a backfill spec, B's kernel slices the outbox log into the
+%% appropriate window and delivers each entry as
+%% `{backfilled, true}`-marked envelopes alongside forward-going
+%% activity.
+%%
+%% Mode shapes (per the Follow activity's `:backfill` field):
+%%   none                   — newer follower sees only forward content
+%%   {last_n, N}            — backfill last N activities (FIFO order)
+%%   {last_t, T, NowFn}     — backfill activities with :published in
+%%                            (Now - T .. Now]. NowFn is a 0-arity fun
+%%                            so tests can fake-time it.
+%%   full                   — backfill the entire outbox
+%%
+%% slice/2 returns the activity list. slice/3 also wraps each entry
+%% with `{backfilled, true}` so projections can decide whether to
+%% re-fold or skip (the §13.3 Backfilled bodies preserve the
+%% original `:id` so replay defence still works on the receiver).
+%%
+%% parse_mode/1 lifts the Follow activity's `:backfill` proplist
+%% (or atom) into the internal mode tuple. Unknown shapes fall back
+%% to `none` — the default open-world policy.
+
+slice(Mode, LogState) ->
+    slice(Mode, LogState, false).
+
+slice(Mode, LogState, Wrap) ->
+    Entries = log:entries(LogState),
+    Slice = case Mode of
+        none                  -> none_entries();
+        full                  -> all_entries(Entries);
+        {last_n, N}           -> last_n_entries(N, Entries);
+        {last_t, T, NowFn}    -> last_t_entries(T, NowFn, Entries);
+        {since_cid, Cid}      -> since_cid_entries(Cid, Entries);
+        _                     -> none_entries()
+    end,
+    case Wrap of
+        true  -> wrap_backfill(Slice);
+        _     -> Slice
+    end.
+
+%% ── Mode-specific entry selection ─────────────────────────────
+
+all_entries(Entries) -> Entries.
+
+none_entries() -> [].
+
+%% last_n_entries/2 — tail N entries in FIFO order.
+
+last_n_entries(N, _) when N =< 0 -> [];
+last_n_entries(N, Entries) ->
+    Len = length(Entries),
+    case Len =< N of
+        true  -> Entries;
+        false -> drop_n(Len - N, Entries)
+    end.
+
+drop_n(0, L) -> L;
+drop_n(_, []) -> [];
+drop_n(N, [_ | Rest]) -> drop_n(N - 1, Rest).
+
+%% last_t_entries/3 — entries whose :published is within the last
+%% T units of (NowFn() - T .. NowFn()]. T and :published are
+%% integers (seconds-since-epoch in production; opaque ints in tests).
+
+last_t_entries(T, NowFn, Entries) when is_integer(T), T >= 0 ->
+    Now = NowFn(),
+    Cutoff = Now - T,
+    [E || E <- Entries, in_window(E, Cutoff, Now)];
+last_t_entries(_, _, _) -> [].
+
+in_window(Activity, Cutoff, Now) ->
+    case envelope:get_field(published, Activity) of
+        {ok, P} when is_integer(P), P > Cutoff, P =< Now -> true;
+        _ -> false
+    end.
+
+%% since_cid_entries/2 — every entry after the one with :id = Cid.
+%% If Cid isn't in the log, returns [] (caller's pointer is stale).
+%% Used by `GET /actors/<id>/outbox?since=Cid` pagination.
+
+since_cid_entries(_Cid, []) -> [];
+since_cid_entries(Cid, [E | Rest]) ->
+    case envelope:get_field(id, E) of
+        {ok, Cid} -> Rest;
+        _         -> since_cid_entries(Cid, Rest)
+    end.
+
+%% wrap_backfill/1 — append `{backfilled, true}` to each entry.
+%% The receiving projection scheduler reads this field and chooses
+%% whether to fold (re-emit) or skip (already known via replay
+%% defence on `:id`).
+
+wrap_backfill([]) -> [];
+wrap_backfill([E | Rest]) ->
+    [E ++ [{backfilled, true}] | wrap_backfill(Rest)].
+
+%% parse_mode/1 — Lift a Follow activity's `:backfill` value into the
+%% internal mode tuple. Accepts:
+%%   nil / not_found       -> none
+%%   none                  -> none
+%%   full                  -> full
+%%   {last_n, N}           -> {last_n, N}     (already-parsed shape)
+%%   {last_t, T, NowFn}    -> pass-through
+%%   Proplist with :mode + :limit / :duration -> parsed
+%% Unknown shape -> none (open-world default).
+
+parse_mode(nil)                  -> none;
+parse_mode(none)                 -> none;
+parse_mode(full)                 -> full;
+parse_mode({last_n, N})          -> {last_n, N};
+parse_mode({last_t, T, NowFn})   -> {last_t, T, NowFn};
+parse_mode({since_cid, Cid})     -> {since_cid, Cid};
+parse_mode(List) when is_list(List) ->
+    case envelope:get_field(mode, List) of
+        {ok, last_n} ->
+            case envelope:get_field(limit, List) of
+                {ok, N} when is_integer(N) -> {last_n, N};
+                _ -> none
+            end;
+        {ok, last_t} ->
+            case envelope:get_field(duration, List) of
+                {ok, T} when is_integer(T) -> {last_t, T, fun () -> 0 end};
+                _ -> none
+            end;
+        {ok, full} -> full;
+        {ok, none} -> none;
+        _ -> none
+    end;
+parse_mode(_) -> none.

next/kernel/bootstrap.erl

@@ -0,0 +1,223 @@
+-module(bootstrap).
+-export([read_genesis/0, read_genesis/1,
+         read_section/2, sections/0, section_subdir/1,
+         default_base/0, ends_with_sx/1,
+         build_genesis/1, verify_genesis/2,
+         cidhash_path/1, write_cidhash/2, read_cidhash/1,
+         load_genesis/1, strip_sx_suffix/1,
+         populate_registry/0,
+         start/3]).
+
+%% Genesis bundle reader per design §12.2.
+%%
+%% read_genesis/0,1 walks the seven canonical section subdirectories
+%% under `next/genesis/`, filters .sx files, reads each file into a
+%% binary, and returns a structured snapshot:
+%%
+%%   {ok, [{Section :: atom,
+%%          [{FileName :: binary, FileBytes :: binary}, ...]},
+%%         ...]}
+%%
+%% Step 4d will compute the bundle CID by hashing the assembled
+%% byte string across all entries; Step 4e will register the parsed
+%% definitions in the kernel registry.
+%%
+%% Port note: this module does NOT parse the .sx contents. The
+%% Erlang-on-SX port has no in-Erlang path from binary bytes to SX
+%% structured terms (same substrate gap that parked Step 3b); the
+%% bundle CID needs only the raw bytes, and registry registration
+%% will happen via an SX-side helper that the kernel hands the
+%% binary contents to. read_genesis/1 ignores its arg in v1 except
+%% to swap the BasePath — `default_base/0` is "next/genesis".
+%%
+%% Port note 2: string-literal binary segments `<<"abc">>` truncate
+%% to one byte in this port, so all path constants are hand-spelled
+%% as integer-segment binaries.
+
+%% ── Public API ──────────────────────────────────────────────────
+
+%% "next/genesis"
+default_base() ->
+    <<110,101,120,116,47,103,101,110,101,115,105,115>>.
+
+read_genesis() ->
+    read_genesis(default_base()).
+
+read_genesis(BasePath) ->
+    {ok, lists:map(
+           fun (S) -> {S, read_section(BasePath, S)} end,
+           sections())}.
+
+sections() ->
+    [activity_types, object_types, projections,
+     validators, codecs, sig_suites, audience].
+
+%% "activity-types"
+section_subdir(activity_types) ->
+    <<97,99,116,105,118,105,116,121,45,116,121,112,101,115>>;
+%% "object-types"
+section_subdir(object_types) ->
+    <<111,98,106,101,99,116,45,116,121,112,101,115>>;
+%% "projections"
+section_subdir(projections) ->
+    <<112,114,111,106,101,99,116,105,111,110,115>>;
+%% "validators"
+section_subdir(validators) ->
+    <<118,97,108,105,100,97,116,111,114,115>>;
+%% "codecs"
+section_subdir(codecs) ->
+    <<99,111,100,101,99,115>>;
+%% "sig-suites"
+section_subdir(sig_suites) ->
+    <<115,105,103,45,115,117,105,116,101,115>>;
+%% "audience"
+section_subdir(audience) ->
+    <<97,117,100,105,101,110,99,101>>.
+
+read_section(BasePath, Section) ->
+    SubDir = section_subdir(Section),
+    %% 47 = '/'
+    Path = <<BasePath/binary, 47, SubDir/binary>>,
+    case file:list_dir(Path) of
+        {ok, Names} ->
+            SxNames = lists:filter(fun (N) -> ends_with_sx(N) end, Names),
+            lists:map(fun (Name) -> read_one(Path, Name) end, SxNames);
+        {error, _} ->
+            []
+    end.
+
+%% Suffix check on the .sx extension. 46='.' 115='s' 120='x'.
+ends_with_sx(<<46, 115, 120>>) -> true;
+ends_with_sx(<<>>) -> false;
+ends_with_sx(<<_, Rest/binary>>) -> ends_with_sx(Rest).
+
+%% ── Internal ────────────────────────────────────────────────────
+
+read_one(DirPath, Name) ->
+    Full = <<DirPath/binary, 47, Name/binary>>,
+    case file:read_file(Full) of
+        {ok, Bytes} -> {Name, Bytes};
+        {error, R}  -> {Name, {error, R}}
+    end.
+
+%% ── Step 4d: bundle CID compute + verify ────────────────────────
+%%
+%% The bundle CID is the canonical content-address of everything in
+%% read_genesis/0's result. We delegate to the host `cid:to_string/1`
+%% BIF (Step 1b substrate): it walks the term via `er-format-value`,
+%% feeds the deterministic textual form into `cid-from-sx`, returns
+%% a CIDv1 (raw codec, sha2-256 multihash) as a binary.
+%%
+%% Design §12.3: at startup the kernel computes this CID and
+%% compares against a hardcoded value (here: a sibling `.cidhash`
+%% file). A mismatch is a hard refuse-to-start.
+
+build_genesis(ReadResult) ->
+    case ReadResult of
+        {ok, Sections} ->
+            Cid = cid:to_string({genesis_bundle, Sections}),
+            {ok, [{cid, Cid}, {sections, Sections}]};
+        Other ->
+            {error, {bad_read_result, Other}}
+    end.
+
+verify_genesis(ReadResult, ExpectedCid) ->
+    case build_genesis(ReadResult) of
+        {ok, [{cid, Cid}, _]} ->
+            case Cid =:= ExpectedCid of
+                true  -> ok;
+                false -> {error, {cid_mismatch, Cid, ExpectedCid}}
+            end;
+        Err -> Err
+    end.
+
+%% Sibling-file CID storage. "/.cidhash" appended to BasePath as
+%% an integer-segment binary (string-literal segments are broken).
+
+%% "/.cidhash" — 47='/' 46='.' c i d h a s h
+cidhash_path(BasePath) ->
+    <<BasePath/binary, 47, 46, 99, 105, 100, 104, 97, 115, 104>>.
+
+write_cidhash(BasePath, Cid) ->
+    file:write_file(cidhash_path(BasePath), Cid).
+
+read_cidhash(BasePath) ->
+    file:read_file(cidhash_path(BasePath)).
+
+%% ── Step 4e: load_genesis → registry ────────────────────────────
+%%
+%% Walks the read_genesis result and registers each file as a
+%% registry entry. The section atom is the registry kind directly
+%% (both name spaces are identical — see Step 4c sections/0 and
+%% Step 5a registry:kinds/0). The entry Name is the filename minus
+%% the `.sx` suffix, kept as a binary; the entry value is the
+%% file's raw bytes.
+%%
+%% Returns `{ok, RegistryState}` on success. Later steps (4f / the
+%% SX-parser bridge) will replace the raw bytes with parsed forms;
+%% the binary stand-in is enough to prove the bridge works.
+
+load_genesis(ReadResult) ->
+    case ReadResult of
+        {ok, Sections} ->
+            {ok, load_sections(Sections, registry:new())};
+        Other ->
+            {error, {bad_read_result, Other}}
+    end.
+
+load_sections([], State) -> State;
+load_sections([{Kind, Entries} | Rest], State) ->
+    load_sections(Rest, load_entries(Kind, Entries, State)).
+
+load_entries(_Kind, [], State) -> State;
+load_entries(Kind, [{Name, Bytes} | Rest], State) ->
+    BaseName = strip_sx_suffix(Name),
+    {ok, NewState} = registry:register(Kind, BaseName, Bytes, State),
+    load_entries(Kind, Rest, NewState).
+
+%% strip_sx_suffix(Binary) — drops the trailing ".sx" if present.
+%% 46='.' 115='s' 120='x'.
+strip_sx_suffix(B) when is_binary(B) ->
+    case ends_with_sx(B) of
+        false -> B;
+        true  -> take_prefix(B, byte_size(B) - 3)
+    end.
+
+take_prefix(_, 0) -> <<>>;
+take_prefix(<<H, Rest/binary>>, N) when N > 0 ->
+    Tail = take_prefix(Rest, N - 1),
+    <<H, Tail/binary>>.
+
+%% populate_registry/0 — load the canonical genesis bundle and
+%% register every entry in the running registry gen_server. The
+%% caller is expected to have started the registry (via
+%% registry:start_link/0) before calling this. Returns the count
+%% of entries registered across all kinds.
+populate_registry() ->
+    {ok, Sections} = read_genesis(),
+    populate_sections(Sections, 0).
+
+populate_sections([], Count) -> Count;
+populate_sections([{Kind, Entries} | Rest], Count) ->
+    populate_sections(Rest, Count + populate_entries(Kind, Entries, 0)).
+
+populate_entries(_, [], Count) -> Count;
+populate_entries(Kind, [{Name, Bytes} | Rest], Count) ->
+    BaseName = strip_sx_suffix(Name),
+    ok = registry:register(Kind, BaseName, Bytes),
+    populate_entries(Kind, Rest, Count + 1).
+
+%% start/3 — one-call bring-up of the kernel substrate. Starts
+%% the registry gen_server, populates it from the canonical
+%% genesis bundle, then starts the nx_kernel gen_server with the
+%% supplied actor identity / key / state. Returns the nx_kernel
+%% Pid (gen_server start_link convention in this port returns the
+%% raw Pid, not {ok, Pid}).
+%%
+%% Tests + production bring-up share this entry point. The
+%% caller is still responsible for starting any application-level
+%% projections and wiring them via nx_kernel:with_projections/1.
+start(ActorId, KeySpec, ActorState) ->
+    registry:start_link(),
+    populate_registry(),
+    nx_kernel:start_link(ActorId, KeySpec, ActorState).

next/kernel/define_registry.erl

@@ -0,0 +1,68 @@
+-module(define_registry).
+-export([fold/2, fold_fn/0, define_kind/1]).
+
+%% Define-registry projection fold — Erlang-fun stand-in for the
+%% genesis `define-registry.sx` body. The intent is identical: a
+%% projection whose state is a registry-shaped property list, fed
+%% by every `Create{Define*{...}}` activity. The SX body would
+%% eventually replace this once an SX-source eval bridge lets the
+%% kernel evaluate the genesis fold directly; until then this
+%% Erlang module proves the meta-projection mechanism wires
+%% through `projection:fold_fn` and `nx_kernel` cleanly.
+%%
+%% State shape mirrors `registry:new()` exactly:
+%%   [{Kind, [{Name, Entry}, ...]}, ...]
+%% so callers can use `registry:lookup/3` etc. on the result.
+%%
+%% Type discrimination uses atoms (`define_activity`, …). Real SX
+%% would carry the string forms ("DefineActivity", …); the bridge
+%% will translate. See define_kind/1 for the mapping.
+
+fold(Activity, State) ->
+    case envelope:get_field(type, Activity) of
+        {ok, create} -> fold_create(Activity, State);
+        _ -> State
+    end.
+
+fold_create(Activity, State) ->
+    case envelope:get_field(object, Activity) of
+        {ok, Obj} ->
+            case envelope:get_field(type, Obj) of
+                {ok, ObjType} ->
+                    case define_kind(ObjType) of
+                        not_a_define -> State;
+                        Kind -> fold_register(Kind, Obj, State)
+                    end;
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+fold_register(Kind, Obj, State) ->
+    case envelope:get_field(name, Obj) of
+        {ok, Name} ->
+            case registry:register(Kind, Name, Obj, State) of
+                {ok, NewState}     -> NewState;
+                {error, unknown_kind} -> State
+            end;
+        not_found -> State
+    end.
+
+%% fold_fn/0 — a 2-arity Erlang fun the projection module plants
+%% in its record's :fold slot. Lets `projection:start_link/3`
+%% wire define-registry directly.
+fold_fn() ->
+    fun (Activity, State) -> fold(Activity, State) end.
+
+%% define_kind/1 — discriminator from the inner Define* object's
+%% :type atom to the registry kind atom. Anything unrecognised
+%% returns not_a_define so the fold treats it as a pass-through.
+
+define_kind(define_activity)   -> activity_types;
+define_kind(define_object)     -> object_types;
+define_kind(define_projection) -> projections;
+define_kind(define_validator)  -> validators;
+define_kind(define_codec)      -> codecs;
+define_kind(define_sig_suite)  -> sig_suites;
+define_kind(define_audience)   -> audience;
+define_kind(_)                 -> not_a_define.

next/kernel/delivery.erl

@@ -0,0 +1,86 @@
+-module(delivery).
+-export([delivery_set/2, delivery_set/3,
+         collect_recipients/1, suppress_self/2, dedup/1,
+         expand_audience/3]).
+
+%% Audience-resolving delivery set computation per design §13.4.
+%%
+%% delivery_set/2(Activity, KernelState) returns a sorted, deduped
+%% list of ActorId atoms — every actor the outgoing Activity needs
+%% to be POSTed to. Sources:
+%%   - Activity's `:to` field   (single ActorId or list)
+%%   - Activity's `:cc` field   (single ActorId or list)
+%%   - audience-symbol expansion of `public` and `followers`
+%%
+%% Self-delivery (the publishing actor reading their own activity
+%% on a peer's behalf) is suppressed.
+%%
+%% Output for Step 7a is the bare ActorId list; Step 8 will resolve
+%% each entry to `{PeerInstanceUrl, ActorId}` via the peer-actors
+%% cache.
+
+delivery_set(Activity, KernelState) ->
+    delivery_set(Activity, KernelState, follower_graph:new()).
+
+delivery_set(Activity, KernelState, FollowerGraph) ->
+    Self = sender(Activity),
+    Raw = collect_recipients(Activity),
+    Expanded = expand_all(Raw, Self, KernelState, FollowerGraph),
+    Suppressed = suppress_self(Expanded, Self),
+    dedup(Suppressed).
+
+%% collect_recipients/1 — flat list from :to + :cc, normalised so
+%% each element is either an ActorId atom or an audience symbol
+%% (`public` / `followers`).
+
+collect_recipients(Activity) ->
+    To = envelope_field_list(to, Activity),
+    Cc = envelope_field_list(cc, Activity),
+    To ++ Cc.
+
+envelope_field_list(Field, Activity) ->
+    case envelope:get_field(Field, Activity) of
+        not_found -> [];
+        {ok, V} when is_list(V) -> V;
+        {ok, V} -> [V]
+    end.
+
+%% expand_audience/3 — `followers` -> the sender's followers
+%% proplist entry from a follower_graph state. `public` for v2
+%% expands to the same list (per design §13.4: practical Public
+%% fan-out is "every follower of the publishing actor"). The
+%% explicit shared-inbox peer-instance model defers to v3.
+%% Other symbols / explicit ActorIds pass through unchanged.
+
+expand_audience(public, Sender, Graph) ->
+    follower_graph:followers(Sender, Graph);
+expand_audience(followers, Sender, Graph) ->
+    follower_graph:followers(Sender, Graph);
+expand_audience(X, _Sender, _Graph) -> [X].
+
+expand_all([], _Self, _State, _Graph) -> [];
+expand_all([X | Rest], Self, State, Graph) ->
+    expand_audience(X, Self, Graph) ++ expand_all(Rest, Self, State, Graph).
+
+suppress_self([], _Self) -> [];
+suppress_self([Self | Rest], Self) -> suppress_self(Rest, Self);
+suppress_self([X | Rest], Self) -> [X | suppress_self(Rest, Self)].
+
+dedup(L) -> dedup_acc(L, []).
+
+dedup_acc([], Acc) -> Acc;
+dedup_acc([X | Rest], Acc) ->
+    case contains(X, Acc) of
+        true  -> dedup_acc(Rest, Acc);
+        false -> dedup_acc(Rest, Acc ++ [X])
+    end.
+
+contains(_, []) -> false;
+contains(X, [X | _]) -> true;
+contains(X, [_ | Rest]) -> contains(X, Rest).
+
+sender(Activity) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, A} -> A;
+        _ -> nil
+    end.

next/kernel/delivery_state.erl

@@ -0,0 +1,209 @@
+-module(delivery_state).
+-export([new/0, fold/2, fold_fn/0,
+         peer_state/2, peers/1,
+         pending/2, attempts/2, next_retry/2, dead_letter/2]).
+
+%% Delivery-state projection. Folds delivery events (enqueue /
+%% delivered / failed / dead_lettered) into a per-peer worker-shaped
+%% snapshot so the outbound queue survives kernel restart. Per design
+%% §13.4 the worker state on restart is loaded from this projection
+%% rather than reconstructed by re-driving the outbox log.
+%%
+%% Event proplist shape:
+%%   [{type, enqueued},      {peer, _}, {activity, _}]
+%%   [{type, delivered},     {peer, _}, {cid, _}]
+%%   [{type, failed},        {peer, _}, {cid, _}, {now, _}]
+%%   [{type, dead_lettered}, {peer, _}, {cid, _}]
+%%
+%% Projection state shape:
+%%   [{PeerId, WorkerProplist}, ...]
+%%
+%% WorkerProplist mirrors `delivery_worker:new/1`'s output so a fresh
+%% gen_server can be hydrated with `delivery_worker:state_from_proj`
+%% (lands when 8b-timer wires up). For Step 8c the projection only
+%% tracks data — Step 8d-restart will wire the hydration helper.
+
+new() -> [].
+
+fold_fn() ->
+    fun (Event, State) -> fold(Event, State) end.
+
+fold(Event, State) ->
+    case envelope:get_field(type, Event) of
+        {ok, enqueued}      -> fold_enqueued(Event, State);
+        {ok, delivered}     -> fold_delivered(Event, State);
+        {ok, failed}        -> fold_failed(Event, State);
+        {ok, dead_lettered} -> fold_dead_lettered(Event, State);
+        _                   -> State
+    end.
+
+fold_enqueued(Event, State) ->
+    case {envelope:get_field(peer, Event),
+          envelope:get_field(activity, Event)} of
+        {{ok, Peer}, {ok, Act}} ->
+            Worker = ensure_peer(Peer, State),
+            Pending = field(pending, Worker),
+            Worker1 = set_field(pending, Pending ++ [Act], Worker),
+            set_peer(Peer, Worker1, State);
+        _ -> State
+    end.
+
+fold_delivered(Event, State) ->
+    case {envelope:get_field(peer, Event),
+          envelope:get_field(cid, Event)} of
+        {{ok, Peer}, {ok, Cid}} ->
+            case find_keyed(Peer, State) of
+                {ok, Worker} ->
+                    Worker1 = drop_pending_by_cid(Cid, Worker),
+                    Worker2 = clear_retry_for(Cid, Worker1),
+                    set_peer(Peer, Worker2, State);
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+fold_failed(Event, State) ->
+    case {envelope:get_field(peer, Event),
+          envelope:get_field(cid, Event),
+          envelope:get_field(now, Event)} of
+        {{ok, Peer}, {ok, Cid}, {ok, Now}} ->
+            case find_keyed(Peer, State) of
+                {ok, Worker} ->
+                    Attempts = field(attempts, Worker),
+                    Current = case find_keyed(Cid, Attempts) of
+                        {ok, N} -> N;
+                        _ -> 0
+                    end,
+                    New = Current + 1,
+                    Attempts1 = set_keyed(Cid, New, Attempts),
+                    Worker1 = set_field(attempts, Attempts1, Worker),
+                    Worker2 = case delivery_worker:backoff_for(New) of
+                        dead_letter ->
+                            dead_letter_pending(Cid, Worker1);
+                        Seconds ->
+                            NR = field(next_retry, Worker1),
+                            NextAt = Now + Seconds,
+                            set_field(next_retry, set_keyed(Cid, NextAt, NR), Worker1)
+                    end,
+                    set_peer(Peer, Worker2, State);
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+fold_dead_lettered(Event, State) ->
+    case {envelope:get_field(peer, Event),
+          envelope:get_field(cid, Event)} of
+        {{ok, Peer}, {ok, Cid}} ->
+            case find_keyed(Peer, State) of
+                {ok, Worker} ->
+                    set_peer(Peer, dead_letter_pending(Cid, Worker), State);
+                _ -> State
+            end;
+        _ -> State
+    end.
+
+%% ── Accessors ─────────────────────────────────────────────────
+
+peer_state(Peer, State) ->
+    case find_keyed(Peer, State) of
+        {ok, Worker} -> {ok, Worker};
+        _            -> not_found
+    end.
+
+peers(State) -> [P || {P, _} <- State].
+
+pending(Peer, State) ->
+    worker_field(Peer, pending, State, []).
+
+attempts(Peer, State) ->
+    worker_field(Peer, attempts, State, []).
+
+next_retry(Peer, State) ->
+    worker_field(Peer, next_retry, State, []).
+
+dead_letter(Peer, State) ->
+    worker_field(Peer, dead_letter, State, []).
+
+%% ── Internal ──────────────────────────────────────────────────
+
+worker_field(Peer, Field, State, Default) ->
+    case find_keyed(Peer, State) of
+        {ok, Worker} ->
+            case find_keyed(Field, Worker) of
+                {ok, V} -> V;
+                _       -> Default
+            end;
+        _ -> Default
+    end.
+
+ensure_peer(Peer, State) ->
+    case find_keyed(Peer, State) of
+        {ok, Worker} -> Worker;
+        _            -> empty_worker(Peer)
+    end.
+
+empty_worker(Peer) ->
+    [{peer, Peer},
+     {pending, []},
+     {attempts, []},
+     {next_retry, []},
+     {dead_letter, []}].
+
+set_peer(Peer, Worker, State) ->
+    set_keyed(Peer, Worker, State).
+
+drop_pending_by_cid(Cid, Worker) ->
+    Pending = field(pending, Worker),
+    Kept = [A || A <- Pending, activity_cid(A) =/= Cid],
+    set_field(pending, Kept, Worker).
+
+clear_retry_for(Cid, Worker) ->
+    A1 = del_keyed(Cid, field(attempts, Worker)),
+    NR1 = del_keyed(Cid, field(next_retry, Worker)),
+    set_field(attempts, A1, set_field(next_retry, NR1, Worker)).
+
+dead_letter_pending(Cid, Worker) ->
+    Pending = field(pending, Worker),
+    {Match, Rest} = split_by_cid(Cid, Pending),
+    DL = field(dead_letter, Worker),
+    Worker1 = set_field(pending, Rest, Worker),
+    Worker2 = case Match of
+        none -> Worker1;
+        Act  -> set_field(dead_letter, DL ++ [Act], Worker1)
+    end,
+    clear_retry_for(Cid, Worker2).
+
+split_by_cid(Cid, List) -> split_by_cid(Cid, List, []).
+split_by_cid(_, [], Acc) -> {none, lists:reverse(Acc)};
+split_by_cid(Cid, [A | Rest], Acc) ->
+    case activity_cid(A) of
+        Cid -> {A, lists:reverse(Acc) ++ Rest};
+        _   -> split_by_cid(Cid, Rest, [A | Acc])
+    end.
+
+activity_cid(Activity) ->
+    case envelope:get_field(id, Activity) of
+        {ok, Cid} -> Cid;
+        _         -> nil
+    end.
+
+field(K, [{K, V} | _]) -> V;
+field(K, [_ | Rest]) -> field(K, Rest);
+field(_, []) -> undefined.
+
+set_field(K, V, []) -> [{K, V}];
+set_field(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_field(K, V, [P | Rest]) -> [P | set_field(K, V, Rest)].
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].
+
+del_keyed(_, []) -> [];
+del_keyed(K, [{K, _} | Rest]) -> Rest;
+del_keyed(K, [P | Rest]) -> [P | del_keyed(K, Rest)].

next/kernel/delivery_worker.erl

@@ -0,0 +1,286 @@
+-module(delivery_worker).
+-behaviour(gen_server).
+-export([new/1, pending/1, peer/1,
+         enqueue_pure/3, drain_pure/1, deliver_one_pure/2,
+         backoff_for/1, schedule_for/1,
+         record_failure_pure/3, record_success_pure/2,
+         next_due_pure/2, attempts_for/2, next_retry_at/2,
+         dead_letter_list/1,
+         start_link/1, start_link/2, stop/1,
+         enqueue/2, flush/1, pending_srv/1, set_dispatch_fn/2]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+
+%% Outbound delivery worker per design §13.4. One gen_server per
+%% peer instance (peer-id atom) holding a FIFO queue of pending
+%% activities to deliver. v2 lands in stages:
+%%
+%%   Step 8a  pure-functional state shape, enqueue / drain /
+%%            schedule semantics + gen_server skeleton + tests
+%%   Step 8b  retry / backoff schedule (30s / 5m / 30m / 6h / 24h)
+%%            + dead-letter list
+%%   Step 8c  delivery-state projection so the queue survives
+%%            kernel restart
+%%   Step 8d  outbox:publish/2 dispatches each delivery-set entry
+%%            to the matching worker
+%%   Step 8e  httpc:request/4 BIF (substrate exception per briefing)
+%%   Step 8f  real HTTP POST through the BIF + content-type wiring
+%%
+%% This file is 8a only — pure state + skeleton gen_server with the
+%% APIs Step 8b-d will fill in. Real HTTP dispatch is stubbed via a
+%% caller-supplied `:dispatch_fn` so tests can intercept and Step 8f
+%% can plug in the live httpc call without touching the queue logic.
+%%
+%% State shape (pure):
+%%   [{peer, PeerId},
+%%    {pending, [Activity, ...]},          %% FIFO; head delivered first
+%%    {attempts, [{Cid, AttemptCount}, ...]},
+%%    {next_retry, [{Cid, NextRetryAt}, ...]}, %% Step 8b-pure
+%%    {dead_letter, [Activity, ...]},
+%%    {dispatch_fn, fun/1 | undefined}]
+%%
+%% gen_server registers under the peer-id atom (one worker per peer);
+%% the same APIs work as pure-functional state transitions for tests.
+
+%% ── Pure-functional API ─────────────────────────────────────────
+
+new(PeerId) ->
+    [{peer, PeerId},
+     {pending, []},
+     {attempts, []},
+     {next_retry, []},
+     {dead_letter, []},
+     {dispatch_fn, undefined}].
+
+pending(State) -> field(pending, State).
+peer(State) -> field(peer, State).
+
+%% enqueue_pure/3 — append an activity to the queue. Returns new
+%% state. Duplicate :id activities aren't deduplicated here — that's
+%% the caller's job (Step 8d will pass each delivery-set entry once).
+
+enqueue_pure(_PeerId, Activity, State) ->
+    Pending = field(pending, State),
+    set_field(pending, Pending ++ [Activity], State).
+
+%% drain_pure/1 — attempt to deliver every queued activity through
+%% the configured dispatch_fn. Returns {NewState, DeliveredCids,
+%% RetryCids}. Activities that fail dispatch stay in :pending with
+%% an incremented attempt counter — Step 8b will use the count to
+%% pick a backoff slot.
+
+drain_pure(State) ->
+    Pending = field(pending, State),
+    drain_loop(Pending, [], State, [], []).
+
+drain_loop([], Kept, State, Delivered, Retry) ->
+    {set_field(pending, Kept, State), Delivered, Retry};
+drain_loop([A | Rest], Kept, State, Delivered, Retry) ->
+    case deliver_one_pure(A, State) of
+        {ok, Cid} ->
+            drain_loop(Rest, Kept, State, Delivered ++ [Cid], Retry);
+        {error, Cid, _Reason} ->
+            State1 = bump_attempt(Cid, State),
+            drain_loop(Rest, Kept ++ [A], State1, Delivered, Retry ++ [Cid])
+    end.
+
+%% deliver_one_pure/2 — single-activity dispatch via the caller-
+%% supplied dispatch_fn. Returns {ok, Cid} on success or {error,
+%% Cid, Reason} on failure. With no dispatch_fn configured returns
+%% {error, _, no_dispatch_fn} so callers know to wire one before
+%% the worker is useful.
+
+deliver_one_pure(Activity, State) ->
+    Cid = activity_cid(Activity),
+    case field(dispatch_fn, State) of
+        undefined -> {error, Cid, no_dispatch_fn};
+        Fn when is_function(Fn, 1) ->
+            case Fn(Activity) of
+                ok              -> {ok, Cid};
+                {ok, _}         -> {ok, Cid};
+                {error, Reason} -> {error, Cid, Reason};
+                Other           -> {error, Cid, {bad_dispatch_return, Other}}
+            end;
+        _ -> {error, Cid, bad_dispatch_fn}
+    end.
+
+%% backoff_for/1 — Step 8a returns the static schedule per the
+%% plan; Step 8b wires it into the retry loop. Attempts are
+%% 1-indexed (first retry uses slot 1).
+%%
+%%   30s / 5m / 30m / 6h / 24h then dead_letter.
+
+backoff_for(0)              -> 0;
+backoff_for(1)              -> 30;
+backoff_for(2)              -> 300;       % 5 * 60
+backoff_for(3)              -> 1800;      % 30 * 60
+backoff_for(4)              -> 21600;     % 6 * 3600
+backoff_for(5)              -> 86400;     % 24 * 3600
+backoff_for(_)              -> dead_letter.
+
+schedule_for(Attempts) ->
+    case backoff_for(Attempts) of
+        dead_letter -> dead_letter;
+        Seconds     -> {retry_in, Seconds}
+    end.
+
+%% ── Step 8b-pure: retry-time bookkeeping ───────────────────────
+%%
+%% `record_failure_pure/3(Cid, Now, State)` — call after a failed
+%% deliver_one. Bumps the per-cid attempt counter; if the new
+%% attempt is past the dead-letter threshold, moves the matching
+%% activity from :pending to :dead_letter. Otherwise records the
+%% next retry time as Now + backoff_for(NewAttempt).
+%%
+%% Real timer wiring (erlang:send_after self-cast on the worker
+%% pid) needs substrate support — Step 8b-timer when that lands.
+%%
+%% `record_success_pure/2(Cid, State)` — clears :attempts and
+%% :next_retry entries for the cid; called after a successful
+%% deliver_one.
+%%
+%% `next_due_pure/2(Now, State)` — returns the list of Cids whose
+%% NextRetryAt has passed, in insertion order.
+
+record_failure_pure(Cid, Now, State) ->
+    Attempts = field(attempts, State),
+    Current  = case find_keyed(Cid, Attempts) of
+        {ok, N} -> N;
+        _       -> 0
+    end,
+    New = Current + 1,
+    State1 = set_field(attempts, set_keyed(Cid, New, Attempts), State),
+    case backoff_for(New) of
+        dead_letter ->
+            move_to_dead_letter(Cid, State1);
+        Seconds ->
+            NextAt = Now + Seconds,
+            NR = field(next_retry, State1),
+            set_field(next_retry, set_keyed(Cid, NextAt, NR), State1)
+    end.
+
+record_success_pure(Cid, State) ->
+    A1 = del_keyed(Cid, field(attempts, State)),
+    NR1 = del_keyed(Cid, field(next_retry, State)),
+    set_field(attempts, A1, set_field(next_retry, NR1, State)).
+
+%% next_due_pure/2 — Cids whose NextRetryAt <= Now. Preserves
+%% insertion order so the worker drains them in FIFO retry order.
+
+next_due_pure(Now, State) ->
+    [Cid || {Cid, At} <- field(next_retry, State), At =< Now].
+
+attempts_for(Cid, State) ->
+    case find_keyed(Cid, field(attempts, State)) of
+        {ok, N} -> N;
+        _       -> 0
+    end.
+
+next_retry_at(Cid, State) ->
+    case find_keyed(Cid, field(next_retry, State)) of
+        {ok, At} -> At;
+        _        -> undefined
+    end.
+
+dead_letter_list(State) -> field(dead_letter, State).
+
+move_to_dead_letter(Cid, State) ->
+    Pending = field(pending, State),
+    {Match, Rest} = take_by_cid(Cid, Pending, [], []),
+    DL = field(dead_letter, State),
+    State1 = set_field(pending, Rest, State),
+    State2 = case Match of
+        none -> State1;
+        Act  -> set_field(dead_letter, DL ++ [Act], State1)
+    end,
+    NR = field(next_retry, State2),
+    set_field(next_retry, del_keyed(Cid, NR), State2).
+
+take_by_cid(_, [], Acc, _) -> {none, lists:reverse(Acc)};
+take_by_cid(Cid, [A | Rest], Acc, _) ->
+    case activity_cid(A) of
+        Cid -> {A, lists:reverse(Acc) ++ Rest};
+        _   -> take_by_cid(Cid, Rest, [A | Acc], 0)
+    end.
+
+%% ── gen_server wrapper ──────────────────────────────────────────
+
+start_link(PeerId) ->
+    start_link(PeerId, undefined).
+
+start_link(PeerId, DispatchFn) ->
+    Pid = gen_server:start_link(delivery_worker, [PeerId, DispatchFn]),
+    erlang:register(PeerId, Pid),
+    Pid.
+
+stop(PeerId) ->
+    R = gen_server:call(PeerId, '$gen_stop'),
+    erlang:unregister(PeerId),
+    R.
+
+enqueue(PeerId, Activity) ->
+    gen_server:call(PeerId, {enqueue, Activity}).
+
+flush(PeerId) ->
+    gen_server:call(PeerId, flush).
+
+pending_srv(PeerId) ->
+    gen_server:call(PeerId, get_pending).
+
+set_dispatch_fn(PeerId, Fn) ->
+    gen_server:call(PeerId, {set_dispatch_fn, Fn}).
+
+%% gen_server callbacks
+
+init([PeerId, DispatchFn]) ->
+    S0 = new(PeerId),
+    {ok, set_field(dispatch_fn, DispatchFn, S0)}.
+
+handle_call({enqueue, Activity}, _From, State) ->
+    {reply, ok, enqueue_pure(field(peer, State), Activity, State)};
+handle_call(flush, _From, State) ->
+    {NewState, Delivered, Retry} = drain_pure(State),
+    {reply, {ok, Delivered, Retry}, NewState};
+handle_call(get_pending, _From, State) ->
+    {reply, field(pending, State), State};
+handle_call({set_dispatch_fn, Fn}, _From, State) ->
+    {reply, ok, set_field(dispatch_fn, Fn, State)}.
+
+handle_cast(_, S) -> {noreply, S}.
+
+handle_info(_, S) -> {noreply, S}.
+
+%% ── Internal ────────────────────────────────────────────────────
+
+activity_cid(Activity) ->
+    case envelope:get_field(id, Activity) of
+        {ok, Cid} -> Cid;
+        _         -> nil
+    end.
+
+bump_attempt(Cid, State) ->
+    Attempts = field(attempts, State),
+    Current = case find_keyed(Cid, Attempts) of
+        {ok, N}     -> N;
+        _           -> 0
+    end,
+    set_field(attempts, set_keyed(Cid, Current + 1, Attempts), State).
+
+field(K, [{K, V} | _]) -> V;
+field(K, [_ | Rest]) -> field(K, Rest);
+field(_, []) -> undefined.
+
+set_field(K, V, []) -> [{K, V}];
+set_field(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_field(K, V, [P | Rest]) -> [P | set_field(K, V, Rest)].
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].
+
+del_keyed(_, []) -> [];
+del_keyed(K, [{K, _} | Rest]) -> Rest;
+del_keyed(K, [P | Rest]) -> [P | del_keyed(K, Rest)].

next/kernel/discovery.erl

@@ -0,0 +1,98 @@
+-module(discovery).
+-export([parse_acct/1, parse_resource/1,
+         actor_url_for/2, webfinger_body/3]).
+
+%% Discovery primitives per design §13.7. Step 10a covers the
+%% local-side webfinger endpoint (responding when a peer asks
+%% "where does acct:alice@here live?"); the peer-fetch direction
+%% (loading a peer's actor doc lazily on first inbound) is Step 10b
+%% and gates on Blockers #2 (native http-request primitive).
+%%
+%% parse_acct/1 — accept a binary in either form:
+%%   <<"acct:alice@host:port">>   (full prefixed URI)
+%%   <<"alice@host:port">>         (bare account, prefix optional)
+%% Returns {ok, User, Host} | {error, Reason}.
+%%
+%% parse_resource/1 — the resource= query parameter from
+%% /.well-known/webfinger. Same shape as parse_acct.
+%%
+%% actor_url_for/2(User, Host) — synthesises the canonical
+%% per-actor URL `<scheme>://<host>/actors/<user>`. v2 hardcodes
+%% http://; TLS / https is v3 (Blockers gate).
+%%
+%% webfinger_body/3 — builds the JSON response body.
+
+%% ── parse_acct / parse_resource ─────────────────────────────────
+
+%% "acct:" -> 5 bytes: 97 99 99 116 58
+parse_acct(Bin) when is_binary(Bin) ->
+    AcctPrefix = <<97,99,99,116,58>>,
+    case strip_prefix(AcctPrefix, Bin) of
+        {ok, Rest} -> split_user_host(Rest);
+        nomatch    -> split_user_host(Bin)
+    end;
+parse_acct(_) -> {error, bad_input}.
+
+parse_resource(Bin) -> parse_acct(Bin).
+
+%% strip_prefix/2 — return {ok, Rest} when Bin starts with Prefix,
+%% else nomatch. Substrate has no proper prefix-match BIF; this
+%% byte-walks.
+
+strip_prefix(<<>>, Rest) -> {ok, Rest};
+strip_prefix(<<B, PRest/binary>>, <<B, RRest/binary>>) ->
+    strip_prefix(PRest, RRest);
+strip_prefix(_, _) -> nomatch.
+
+%% split_user_host/1 — split a `user@host[:port]` binary at the
+%% first `@`. Returns {ok, User, Host} where Host may include the
+%% optional port suffix.
+
+split_user_host(Bin) ->
+    case split_at(64, Bin) of  % 64 = '@'
+        {Before, After} when byte_size(Before) > 0, byte_size(After) > 0 ->
+            {ok, Before, After};
+        _ ->
+            {error, bad_acct}
+    end.
+
+split_at(Byte, Bin) ->
+    split_at(Byte, Bin, <<>>).
+
+split_at(_, <<>>, Acc) ->
+    {Acc, <<>>};
+split_at(Byte, <<Byte, Rest/binary>>, Acc) ->
+    {Acc, Rest};
+split_at(Byte, <<B, Rest/binary>>, Acc) ->
+    split_at(Byte, Rest, <<Acc/binary, B>>).
+
+%% ── URL synthesis ──────────────────────────────────────────────
+
+%% "http://"  -> 7 bytes  | "/actors/" -> 8 bytes
+actor_url_for(User, Host) ->
+    Pre = <<104,116,116,112,58,47,47>>,            % "http://"
+    Mid = <<47,97,99,116,111,114,115,47>>,         % "/actors/"
+    <<Pre/binary, Host/binary, Mid/binary, User/binary>>.
+
+%% ── webfinger JSON body ────────────────────────────────────────
+%%
+%% Mastodon-shape per RFC 7033:
+%%   {"subject":"acct:<user>@<host>",
+%%    "links":[{"rel":"self",
+%%              "type":"application/activity+json",
+%%              "href":"<actor_url>"}]}
+%%
+%% Hand-rolled byte concatenation — no JSON BIF on this port. The
+%% caller has already validated User + Host; we don't need to
+%% re-escape (Mastodon's webfinger inputs are alphanumeric +
+%% .-_ in practice).
+
+webfinger_body(User, Host, ActorUrl) ->
+    AcctPre = <<123,34,115,117,98,106,101,99,116,34,58,34,97,99,99,116,58>>,  % '{"subject":"acct:'
+    AcctAt  = <<64>>,                                                          % '@'
+    LinksHd = <<34,44,34,108,105,110,107,115,34,58,91,123,34,114,101,108,34,58,34,115,101,108,102,34,44,
+                34,116,121,112,101,34,58,34,97,112,112,108,105,99,97,116,105,111,110,47,97,99,116,
+                105,118,105,116,121,43,106,115,111,110,34,44,34,104,114,101,102,34,58,34>>,         % '","links":[{"rel":"self","type":"application/activity+json","href":"'
+    LinksTl = <<34,125,93,125,10>>,                                            % '"}]}\n'
+    <<AcctPre/binary, User/binary, AcctAt/binary, Host/binary,
+      LinksHd/binary, ActorUrl/binary, LinksTl/binary>>.

next/kernel/endorsement_state.erl

@@ -0,0 +1,118 @@
+-module(endorsement_state).
+-export([new/0, fold/2, fold_fn/0,
+         counters_for/2, total_for/2, kinds_for/2,
+         endorsers_for/3, has_endorsed/4]).
+
+%% Endorsement counter projection. Folds Endorse activities into a
+%% per-target-Cid + per-kind counter so projections can serve
+%% "how many likes does this Note have" / "list everyone who shared
+%% this Announce" queries.
+%%
+%% Endorse envelope shape (per next/genesis/activity-types/endorse.sx):
+%%   [{type, endorse},
+%%    {actor, ActorId},
+%%    {object, TargetCidBinary},
+%%    {kind, KindAtomOrBinary},
+%%    ...]
+%%
+%% State shape:
+%%   [{TargetCid, [{Kind, [{ActorId, Count}, ...]}, ...]}, ...]
+%%
+%% Each ActorId can endorse the same target multiple times under
+%% the same kind (e.g. like → unlike → like → ...); the counter
+%% tracks how many *net* endorsement events fired. Step 11b ships
+%% the additive counter only; the unlike / un-endorse semantics
+%% (Undo{Endorse}) and reaction-toggling defer to a follow-up.
+
+new() -> [].
+
+fold_fn() ->
+    fun (Activity, State) -> fold(Activity, State) end.
+
+fold(Activity, State) ->
+    case envelope:get_field(type, Activity) of
+        {ok, endorse} -> fold_endorse(Activity, State);
+        _             -> State
+    end.
+
+fold_endorse(Activity, State) ->
+    case {envelope:get_field(actor, Activity),
+          envelope:get_field(object, Activity),
+          envelope:get_field(kind, Activity)} of
+        {{ok, Actor}, {ok, Cid}, {ok, Kind}} ->
+            bump(Cid, Kind, Actor, State);
+        _ ->
+            State
+    end.
+
+bump(Cid, Kind, Actor, State) ->
+    KindMap = case find_keyed(Cid, State) of
+        {ok, KM} -> KM;
+        _        -> []
+    end,
+    ActorMap = case find_keyed(Kind, KindMap) of
+        {ok, AM} -> AM;
+        _        -> []
+    end,
+    Current = case find_keyed(Actor, ActorMap) of
+        {ok, N} -> N;
+        _       -> 0
+    end,
+    ActorMap1 = set_keyed(Actor, Current + 1, ActorMap),
+    KindMap1  = set_keyed(Kind, ActorMap1, KindMap),
+    set_keyed(Cid, KindMap1, State).
+
+%% ── Read-side accessors ───────────────────────────────────────
+
+%% counters_for(Cid, State) -> [{Kind, TotalCount}, ...]
+%% Sum per-kind across all endorsers.
+
+counters_for(Cid, State) ->
+    case find_keyed(Cid, State) of
+        {ok, KindMap} ->
+            [{K, sum_counts(AM)} || {K, AM} <- KindMap];
+        _ -> []
+    end.
+
+total_for(Cid, State) ->
+    lists:foldl(fun ({_, N}, Acc) -> N + Acc end, 0, counters_for(Cid, State)).
+
+kinds_for(Cid, State) ->
+    [K || {K, _} <- counters_for(Cid, State)].
+
+endorsers_for(Cid, Kind, State) ->
+    case find_keyed(Cid, State) of
+        {ok, KindMap} ->
+            case find_keyed(Kind, KindMap) of
+                {ok, AM} -> [A || {A, _} <- AM];
+                _        -> []
+            end;
+        _ -> []
+    end.
+
+has_endorsed(Actor, Cid, Kind, State) ->
+    case find_keyed(Cid, State) of
+        {ok, KindMap} ->
+            case find_keyed(Kind, KindMap) of
+                {ok, AM} ->
+                    case find_keyed(Actor, AM) of
+                        {ok, N} -> N > 0;
+                        _       -> false
+                    end;
+                _ -> false
+            end;
+        _ -> false
+    end.
+
+%% ── Internal ──────────────────────────────────────────────────
+
+sum_counts([]) -> 0;
+sum_counts([{_, N} | Rest]) -> N + sum_counts(Rest).
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].

next/kernel/envelope.erl

@@ -0,0 +1,177 @@
+-module(envelope).
+-export([validate_shape/1, get_field/2, canonical_bytes/1, verify_signature/2]).
+
+%% Activity envelope per design §3.1.
+%%
+%% Erlang maps (#{...}) are not supported by this port, so envelopes
+%% are represented as property lists of {atom_key, value} pairs. This
+%% port's binary syntax also can't carry string literals; values that
+%% would naturally be binaries in real Erlang are kept as atoms or
+%% integer-segment binaries in the test corpus.
+%%
+%% Required fields: id, type, actor, published, signature.
+%% The signature value is itself a property list with key_id,
+%% algorithm, value.
+%%
+%% validate_shape/1 returns ok | {error, Reason}. Reasons:
+%%   not_a_proplist
+%%   {missing_field, FieldName}
+%%   {bad_signature, BadSigReason}
+%%
+%% get_field/2 returns {ok, Value} | not_found.
+
+validate_shape(Env) when is_list(Env) ->
+    case check_required([id, type, actor, published, signature], Env) of
+        ok -> validate_signature_shape(Env);
+        Err -> Err
+    end;
+validate_shape(_) ->
+    {error, not_a_proplist}.
+
+get_field(_, []) -> not_found;
+get_field(K, [{K, V} | _]) -> {ok, V};
+get_field(K, [_ | Rest]) -> get_field(K, Rest).
+
+check_required([], _) -> ok;
+check_required([F | Rest], Env) ->
+    case get_field(F, Env) of
+        {ok, _} -> check_required(Rest, Env);
+        not_found -> {error, {missing_field, F}}
+    end.
+
+validate_signature_shape(Env) ->
+    {ok, Sig} = get_field(signature, Env),
+    case is_list(Sig) of
+        true ->
+            case check_required([key_id, algorithm, value], Sig) of
+                ok -> ok;
+                {error, {missing_field, F}} ->
+                    {error, {bad_signature, {missing_field, F}}}
+            end;
+        false ->
+            {error, {bad_signature, not_a_proplist}}
+    end.
+
+%% canonical_bytes/1 — the byte string the signature covers.
+%%
+%% Real fed-sx will use dag-cbor over a JSON-LD-canonicalised form
+%% (design §3.2). For milestone 1 we stand in for that with the host
+%% BIF `cid:to_string/1`, which produces a CIDv1 over the deterministic
+%% textual form of the term. Two prior steps make this work:
+%%   1. The signature pair is stripped (sig covers everything except
+%%      itself).
+%%   2. The top-level property list is sorted by key so field order in
+%%      the source envelope is not load-bearing.
+%%
+%% The result is an Erlang binary suitable as the sig-cover input.
+
+canonical_bytes(Env) when is_list(Env) ->
+    Stripped = strip_signature(Env),
+    Sorted = sort_pairs(Stripped),
+    cid:to_string(Sorted).
+
+strip_signature([]) -> [];
+strip_signature([{signature, _} | Rest]) -> strip_signature(Rest);
+strip_signature([P | Rest]) -> [P | strip_signature(Rest)].
+
+sort_pairs([]) -> [];
+sort_pairs([H | T]) -> insert_pair(H, sort_pairs(T)).
+
+insert_pair(P, []) -> [P];
+insert_pair({K1, V1}, [{K2, V2} | Rest]) ->
+    case K1 < K2 of
+        true  -> [{K1, V1}, {K2, V2} | Rest];
+        false -> [{K2, V2} | insert_pair({K1, V1}, Rest)]
+    end.
+
+%% verify_signature/2 — time-aware sig verification per design §9.6.
+%%
+%% Activity carries a `signature` proplist with `key_id`, `algorithm`,
+%% `value`. ActorState carries `public_keys` — a list of key proplists
+%% with `id`, `created`, optionally `superseded_at`, and `value` (the
+%% key material).
+%%
+%% A key is active at time T iff `created =< T` AND
+%% (no `superseded_at` OR T < `superseded_at`). Verification picks the
+%% first matching active key whose `id == signature.key_id` at the
+%% activity's `published` timestamp, then recomputes the MAC
+%% `crypto:hash(sha256, <<KeyMaterial/binary, CanonicalBytes/binary>>)`
+%% and compares it to `signature.value`.
+%%
+%% Returns ok | {error, Reason}. Reasons:
+%%   no_signature | no_key_id | no_published | no_keys |
+%%   no_active_key | bad_signature
+%%
+%% Real RSA-SHA256 / Ed25519 verification is deferred to milestone 2:
+%% Phase 8 only ships `crypto:hash/2`, so we stand in with an HMAC-shaped
+%% MAC that exercises the same key-lookup and canonical-bytes pipeline.
+
+verify_signature(Activity, ActorState) ->
+    case get_field(signature, Activity) of
+        not_found -> {error, no_signature};
+        {ok, Sig} ->
+            case get_field(key_id, Sig) of
+                not_found -> {error, no_key_id};
+                {ok, KeyId} ->
+                    case get_field(published, Activity) of
+                        not_found -> {error, no_published};
+                        {ok, Published} ->
+                            verify_with_keys(Activity, Sig, KeyId,
+                                             Published, ActorState)
+                    end
+            end
+    end.
+
+verify_with_keys(Activity, Sig, KeyId, Published, ActorState) ->
+    case get_field(public_keys, ActorState) of
+        not_found -> {error, no_keys};
+        {ok, Keys} ->
+            case find_active_key(KeyId, Published, Keys) of
+                not_found -> {error, no_active_key};
+                {ok, Key} -> verify_mac(Activity, Sig, Key)
+            end
+    end.
+
+find_active_key(_, _, []) -> not_found;
+find_active_key(KeyId, Now, [Key | Rest]) ->
+    case is_matching_active_key(Key, KeyId, Now) of
+        true -> {ok, Key};
+        false -> find_active_key(KeyId, Now, Rest)
+    end.
+
+is_matching_active_key(Key, WantId, Now) ->
+    case get_field(id, Key) of
+        {ok, WantId} -> is_active_at(Key, Now);
+        _ -> false
+    end.
+
+is_active_at(Key, Now) ->
+    case get_field(created, Key) of
+        not_found -> false;
+        {ok, Created} ->
+            case Now >= Created of
+                false -> false;
+                true ->
+                    case get_field(superseded_at, Key) of
+                        not_found -> true;
+                        {ok, SupAt} -> Now < SupAt
+                    end
+            end
+    end.
+
+verify_mac(Activity, Sig, Key) ->
+    case get_field(value, Sig) of
+        not_found -> {error, bad_signature};
+        {ok, SigValue} ->
+            case get_field(value, Key) of
+                not_found -> {error, bad_signature};
+                {ok, KeyMat} ->
+                    Bytes = canonical_bytes(Activity),
+                    Computed = crypto:hash(sha256,
+                        <<KeyMat/binary, Bytes/binary>>),
+                    case SigValue =:= Computed of
+                        true -> ok;
+                        false -> {error, bad_signature}
+                    end
+            end
+    end.

next/kernel/follower_graph.erl

@@ -0,0 +1,237 @@
+-module(follower_graph).
+-export([fold/2, fold_fn/0, new/0, lookup/2, actors/1,
+         following/2, followers/2,
+         pending_outbound/2, pending_inbound/2,
+         is_following/3, has_follower/3,
+         is_pending_outbound/3, is_pending_inbound/3]).
+
+%% Follower-graph projection — Erlang-fun stand-in for the genesis
+%% `follower-graph.sx` body. Tracks per-actor follow relationships
+%% per design §13.2:
+%%
+%%   Follow {actor: A, object: B}      A asks to follow B
+%%   Accept {actor: B, object: F}      B accepts A's Follow F (= F.actor → F.object)
+%%   Reject {actor: B, object: F}      B rejects A's Follow F
+%%   Undo   {actor: A, object: F}      A retracts F or unfollows
+%%
+%% Where F = Follow{A→B} is embedded as the activity's :object
+%% proplist for Accept / Reject / Undo.
+%%
+%% State shape:
+%%   [{ActorId, ActorEntry}, ...]
+%%
+%% ActorEntry = [{following,        [PeerId, ...]},
+%%               {followers,        [PeerId, ...]},
+%%               {pending_outbound, [PeerId, ...]},  %% I asked, no answer yet
+%%               {pending_inbound,  [PeerId, ...]}]  %% asked me, I haven't answered
+%%
+%% Sets keep insertion order; duplicates aren't added. lists:keyfind/
+%% keymember aren't in this substrate, so local find_keyed/has_keyed/
+%% set_keyed helpers (same convention as actor_state, define_registry,
+%% nx_kernel).
+
+%% ── Public API ──────────────────────────────────────────────────
+
+new() -> [].
+
+actors(State) -> [Id || {Id, _Entry} <- State].
+
+lookup(ActorId, State) ->
+    case find_keyed(ActorId, State) of
+        {ok, Entry} -> {ok, Entry};
+        _           -> not_found
+    end.
+
+following(ActorId, State)        -> entry_field(ActorId, following, State).
+followers(ActorId, State)        -> entry_field(ActorId, followers, State).
+pending_outbound(ActorId, State) -> entry_field(ActorId, pending_outbound, State).
+pending_inbound(ActorId, State)  -> entry_field(ActorId, pending_inbound, State).
+
+is_following(ActorId, PeerId, State) ->
+    contains(PeerId, following(ActorId, State)).
+
+has_follower(ActorId, PeerId, State) ->
+    contains(PeerId, followers(ActorId, State)).
+
+is_pending_outbound(ActorId, PeerId, State) ->
+    contains(PeerId, pending_outbound(ActorId, State)).
+
+is_pending_inbound(ActorId, PeerId, State) ->
+    contains(PeerId, pending_inbound(ActorId, State)).
+
+%% ── Fold dispatch ───────────────────────────────────────────────
+
+fold(Activity, State) ->
+    case envelope:get_field(type, Activity) of
+        {ok, follow} -> fold_follow(Activity, State);
+        {ok, accept} -> fold_accept(Activity, State);
+        {ok, reject} -> fold_reject(Activity, State);
+        {ok, undo}   -> fold_undo(Activity, State);
+        _            -> State
+    end.
+
+fold_fn() ->
+    fun (Activity, State) -> fold(Activity, State) end.
+
+%% Follow {actor: A, object: B}:
+%%   add B to A's pending_outbound
+%%   add A to B's pending_inbound
+fold_follow(Activity, State) ->
+    case follow_actor_object(Activity) of
+        {ok, A, B} when A =/= B ->
+            S1 = add_to_field(A, pending_outbound, B, State),
+            add_to_field(B, pending_inbound, A, S1);
+        _ -> State
+    end.
+
+%% Accept {actor: B, object: Follow{A→B}}:
+%%   move A from B's pending_inbound to B's followers
+%%   move B from A's pending_outbound to A's following
+fold_accept(Activity, State) ->
+    case nested_follow_actor_object(Activity) of
+        {ok, B, A, OrigA, OrigB} when B =:= OrigB, A =:= OrigA, A =/= B ->
+            S1 = move_field(B, pending_inbound, followers, A, State),
+            move_field(A, pending_outbound, following, B, S1);
+        _ -> State
+    end.
+
+%% Reject {actor: B, object: Follow{A→B}}:
+%%   drop A from B's pending_inbound
+%%   drop B from A's pending_outbound
+fold_reject(Activity, State) ->
+    case nested_follow_actor_object(Activity) of
+        {ok, B, A, OrigA, OrigB} when B =:= OrigB, A =:= OrigA, A =/= B ->
+            S1 = drop_from_field(B, pending_inbound, A, State),
+            drop_from_field(A, pending_outbound, B, S1);
+        _ -> State
+    end.
+
+%% Undo {actor: X, object: Follow{A→B}}:
+%%   Only the original Follow's actor (A) can Undo it.
+%%   Drops A↔B from every list on either side.
+fold_undo(Activity, State) ->
+    case nested_follow_actor_object(Activity) of
+        {ok, X, OrigA, OrigA, OrigB} when X =:= OrigA, OrigA =/= OrigB ->
+            S1 = drop_from_field(OrigA, following,        OrigB, State),
+            S2 = drop_from_field(OrigA, pending_outbound, OrigB, S1),
+            S3 = drop_from_field(OrigB, followers,        OrigA, S2),
+            drop_from_field(OrigB, pending_inbound, OrigA, S3);
+        _ -> State
+    end.
+
+%% ── Extraction helpers ─────────────────────────────────────────
+
+follow_actor_object(Activity) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, A} ->
+            case envelope:get_field(object, Activity) of
+                {ok, B} when is_atom(B) -> {ok, A, B};
+                _ -> not_follow
+            end;
+        _ -> not_follow
+    end.
+
+%% nested_follow_actor_object/1 — pull (Actor, FollowActor, FollowObject)
+%% out of an envelope whose :object is itself a Follow proplist.
+%% Returns {ok, OuterActor, InferredPeer, InnerActor, InnerObject}.
+nested_follow_actor_object(Activity) ->
+    case envelope:get_field(actor, Activity) of
+        {ok, Outer} ->
+            case envelope:get_field(object, Activity) of
+                {ok, Inner} when is_list(Inner) ->
+                    case nested_is_follow(Inner) of
+                        true  ->
+                            case {envelope:get_field(actor, Inner),
+                                  envelope:get_field(object, Inner)} of
+                                {{ok, IA}, {ok, IO}} when is_atom(IO) ->
+                                    {ok, Outer, peer_from_inner(Outer, IA, IO), IA, IO};
+                                _ -> not_a_follow_wrapper
+                            end;
+                        false -> not_a_follow_wrapper
+                    end;
+                _ -> not_a_follow_wrapper
+            end;
+        _ -> not_a_follow_wrapper
+    end.
+
+nested_is_follow(Inner) ->
+    case envelope:get_field(type, Inner) of
+        {ok, follow} -> true;
+        _ -> false
+    end.
+
+%% peer_from_inner — for an Accept/Reject by B of Follow{A→B},
+%% Outer = B; the "peer" we move state for is A. For an Undo by A,
+%% Outer = A; the peer is B. Picking the inner actor/object that
+%% isn't Outer gives us the right pair-mate.
+peer_from_inner(Outer, IA, _IO) when Outer =:= IA -> IA;
+peer_from_inner(_Outer, IA, _IO) -> IA.
+
+%% ── Entry / field accessors ────────────────────────────────────
+
+entry_field(ActorId, Field, State) ->
+    case find_keyed(ActorId, State) of
+        {ok, Entry} ->
+            case find_keyed(Field, Entry) of
+                {ok, Val} -> Val;
+                _ -> []
+            end;
+        _ -> []
+    end.
+
+empty_entry() ->
+    [{following, []},
+     {followers, []},
+     {pending_outbound, []},
+     {pending_inbound, []}].
+
+ensure_entry(ActorId, State) ->
+    case find_keyed(ActorId, State) of
+        {ok, _} -> State;
+        _       -> State ++ [{ActorId, empty_entry()}]
+    end.
+
+add_to_field(ActorId, Field, PeerId, State) ->
+    S1 = ensure_entry(ActorId, State),
+    {ok, Entry} = find_keyed(ActorId, S1),
+    Current = entry_field(ActorId, Field, S1),
+    NewList = case contains(PeerId, Current) of
+        true  -> Current;
+        false -> Current ++ [PeerId]
+    end,
+    NewEntry = set_keyed(Field, NewList, Entry),
+    set_keyed(ActorId, NewEntry, S1).
+
+drop_from_field(ActorId, Field, PeerId, State) ->
+    case find_keyed(ActorId, State) of
+        {ok, Entry} ->
+            Current = entry_field(ActorId, Field, State),
+            NewList = remove_member(PeerId, Current),
+            NewEntry = set_keyed(Field, NewList, Entry),
+            set_keyed(ActorId, NewEntry, State);
+        _ -> State
+    end.
+
+move_field(ActorId, FromField, ToField, PeerId, State) ->
+    S1 = drop_from_field(ActorId, FromField, PeerId, State),
+    add_to_field(ActorId, ToField, PeerId, S1).
+
+%% ── List helpers ───────────────────────────────────────────────
+
+contains(_, []) -> false;
+contains(X, [X | _]) -> true;
+contains(X, [_ | Rest]) -> contains(X, Rest).
+
+remove_member(_, []) -> [];
+remove_member(X, [X | Rest]) -> remove_member(X, Rest);
+remove_member(X, [Y | Rest]) -> [Y | remove_member(X, Rest)].
+
+%% ── Keyed-list helpers ─────────────────────────────────────────
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].

next/kernel/log.erl

@@ -0,0 +1,362 @@
+-module(log).
+-export([open/2, open_disk/2, open_disk/3,
+         append/2, tip/1, replay/3, entries/1,
+         segments/1]).
+
+%% Per-actor activity log — the canonical record of everything an
+%% actor has emitted, in chronological order. Per design §15.2 this
+%% lives on disk as numbered segment files; v1 started with an
+%% in-memory backend (Step 3a) so the API + seq-number machinery
+%% could be locked down before on-disk persistence (Step 3b) and
+%% segment rotation (Step 3c.a — this revision).
+%%
+%% On-disk layout:
+%%   <BasePath>/<ActorId>-NNNNNN.log
+%%
+%% NNNNNN is a 6-digit zero-padded segment index (000000..999999) so
+%% file:list_dir's alphabetical ordering coincides with numeric. Each
+%% segment file is the concat of length-prefixed frames; each frame
+%% is `<<Len:32/big>>` + `term_codec:encode(Activity)`.
+%%
+%% In-memory state (a property list):
+%%   [{actor, ActorId},
+%%    {base, BasePath},          %% binary | charlist
+%%    {seq, NextSeq},            %% next seq the log will assign
+%%    {entries, [Activity, ...]}, %% flat, append order, oldest first
+%%    {persisted, true|false},   %% does append write through?
+%%    {seg_size, MaxBytes},      %% rotate when active segment > this
+%%    {seg_lens, [N0, N1, ...]}]  %% entry count per segment in order
+%%
+%% `seg_lens` is the sole bookkeeping needed to compute (a) which
+%% segment any given seq lives in, and (b) which slice of `entries`
+%% is the active segment's contents to rewrite on append. The last
+%% element is the active segment's length.
+
+%% In-memory only — atoms accepted as BasePath for back-compat with
+%% Step 3a tests that just want the API surface.
+open(ActorId, BasePath) ->
+    {ok, [{actor, ActorId}, {base, BasePath},
+          {seq, 0}, {entries, []},
+          {persisted, false}]}.
+
+%% Disk-backed; default segment size = effectively unlimited (no
+%% rotation). Use open_disk/3 with {segment_size, N} to enable.
+open_disk(ActorId, BasePath) ->
+    open_disk(ActorId, BasePath, [{segment_size, 1073741824}]). %% 1 GiB
+
+open_disk(ActorId, BasePath, Opts) ->
+    SegSize = proplist_get(segment_size, Opts, 1073741824),
+    case load_all_segments(ActorId, BasePath) of
+        {ok, SegEntries} ->
+            %% SegEntries :: [[Entry, ...]] in segment-index order
+            %% (empty list when no segments exist on disk).
+            Lens0 = [length(S) || S <- SegEntries],
+            %% Always have at least one active segment, even if empty.
+            Lens = case Lens0 of
+                       [] -> [0];
+                       _ -> Lens0
+                   end,
+            Flat = flatten_segs(SegEntries),
+            State = [{actor, ActorId}, {base, BasePath},
+                     {seq, length(Flat)},
+                     {entries, Flat},
+                     {persisted, true},
+                     {seg_size, SegSize},
+                     {seg_lens, Lens}],
+            {ok, State};
+        {error, _} = E ->
+            E
+    end.
+
+append(LogState, Activity) ->
+    Seq = field(seq, LogState),
+    Entries = field(entries, LogState),
+    case lookup(persisted, LogState) of
+        true ->
+            SegLens = field(seg_lens, LogState),
+            SegSize = field(seg_size, LogState),
+            {NewSegLens, ActiveIdx, ActiveEntries} =
+                place_append(Entries, Activity, SegLens, SegSize),
+            Path = segment_path(field(actor, LogState),
+                                field(base, LogState),
+                                ActiveIdx),
+            ok = write_segment(Path, ActiveEntries),
+            NewState = replace_field(seq, Seq + 1,
+                       replace_field(entries, Entries ++ [Activity],
+                       replace_field(seg_lens, NewSegLens, LogState))),
+            {ok, NewState, Seq};
+        _ ->
+            NewState = replace_field(seq, Seq + 1,
+                       replace_field(entries, Entries ++ [Activity],
+                                     LogState)),
+            {ok, NewState, Seq}
+    end.
+
+tip(LogState) ->
+    field(seq, LogState).
+
+replay(LogState, InitAcc, Fun) ->
+    Entries = field(entries, LogState),
+    replay_loop(Entries, 0, InitAcc, Fun).
+
+entries(LogState) ->
+    field(entries, LogState).
+
+%% Debug accessor: returns the in-memory seg_lens (count per segment
+%% in index order). Used by rotation tests to assert that rotation
+%% happened.
+segments(LogState) ->
+    case lookup(seg_lens, LogState) of
+        undefined -> [];
+        L -> L
+    end.
+
+%% --- internals ---
+
+replay_loop([], _, Acc, _) -> Acc;
+replay_loop([Act | Rest], Seq, Acc, Fun) ->
+    replay_loop(Rest, Seq + 1, Fun(Act, Seq, Acc), Fun).
+
+%% place_append/4 decides whether the new Activity extends the current
+%% active segment or opens a fresh one, returning the resulting
+%% seg_lens, the active segment's index, and the active segment's
+%% complete entry list (the slice that needs to be (re)written to
+%% disk).
+%%
+%% Rotation rule: if the active segment already on disk is at or past
+%% the size threshold (encoded_size(OldActive) >= SegSize) AND it
+%% already holds at least one entry, the new Activity opens a new
+%% segment. A single entry larger than the threshold therefore lives
+%% on its own — we never recurse rotating a one-entry segment.
+%%
+%% This is decided BEFORE the append (looking at the pre-append size),
+%% so each segment file is written exactly once per append cycle.
+place_append(OldEntries, Activity, SegLens, SegSize) ->
+    {Pre, Last} = split_last(SegLens),
+    PreCount = sum(Pre),
+    OldActive = drop(PreCount, OldEntries),
+    OldActiveSize = encoded_size(OldActive),
+    case (OldActiveSize >= SegSize) andalso (Last >= 1) of
+        true ->
+            %% Rotate: new entry starts a brand-new segment.
+            NewSegLens = SegLens ++ [1],
+            NewActiveIdx = length(SegLens),
+            {NewSegLens, NewActiveIdx, [Activity]};
+        false ->
+            %% Stay: extend current active.
+            NewSegLens = Pre ++ [Last + 1],
+            NewActiveIdx = length(Pre),
+            {NewSegLens, NewActiveIdx, OldActive ++ [Activity]}
+    end.
+
+split_last([X]) -> {[], X};
+split_last([H | T]) ->
+    {Tl, Last} = split_last(T),
+    {[H | Tl], Last}.
+
+sum(L) -> sum_(L, 0).
+sum_([], A) -> A;
+sum_([H | T], A) -> sum_(T, A + H).
+
+drop(0, L) -> L;
+drop(_, []) -> [];
+drop(N, [_ | T]) -> drop(N - 1, T).
+
+%% flatten_segs/1 — concat a list of segments (each itself a list of
+%% entries) into a single flat list, preserving order. Used by
+%% open_disk to assemble the on-disk activity history from per-
+%% segment loads. Implemented locally because lists:append/1 isn't
+%% registered in this port — only lists:append/2.
+flatten_segs([]) -> [];
+flatten_segs([Seg | Rest]) -> Seg ++ flatten_segs(Rest).
+
+encoded_size(Entries) ->
+    byte_size(list_to_binary(
+        [frame(term_codec:encode(E)) || E <- Entries])).
+
+%% Try to read every segment file under BasePath matching the actor.
+%% Returns {ok, [[Entry, ...]]} where the outer list is in segment-
+%% index order. Empty when no segments exist.
+load_all_segments(ActorId, BasePath) ->
+    %% list_dir returns {ok, [Binary]} of entry names in sorted order
+    %% per fed-prims contract.
+    BaseChars = base_chars(BasePath),
+    case file:list_dir(BaseChars) of
+        {ok, Names} ->
+            %% Erlang string literals are NOT charlists in this port,
+            %% so build prefix/suffix as explicit char-code lists.
+            Prefix = atom_to_list(ActorId) ++ [$-],
+            Suffix = [$., $l, $o, $g],
+            Indices = collect_segment_indices(Names, Prefix, Suffix),
+            read_segments_in_order(Indices, ActorId, BasePath, []);
+        {error, enoent} ->
+            {ok, []};
+        {error, R} ->
+            {error, {read, R}}
+    end.
+
+collect_segment_indices([], _, _) -> [];
+collect_segment_indices([Name | Rest], Prefix, Suffix) ->
+    case parse_segment_name(Name, Prefix, Suffix) of
+        {ok, N} ->
+            [N | collect_segment_indices(Rest, Prefix, Suffix)];
+        not_ours ->
+            collect_segment_indices(Rest, Prefix, Suffix)
+    end.
+
+parse_segment_name(NameBin, Prefix, Suffix) when is_binary(NameBin) ->
+    parse_segment_name(binary_to_list(NameBin), Prefix, Suffix);
+parse_segment_name(Name, Prefix, Suffix) ->
+    case strip_prefix(Name, Prefix) of
+        {ok, Rest} ->
+            case strip_suffix(Rest, Suffix) of
+                {ok, NumStr} ->
+                    case is_all_digits(NumStr) of
+                        true -> {ok, list_to_integer(NumStr)};
+                        false -> not_ours
+                    end;
+                not_ours -> not_ours
+            end;
+        not_ours -> not_ours
+    end.
+
+strip_prefix(Str, []) -> {ok, Str};
+strip_prefix([C | Rest], [P | PRest]) ->
+    case C =:= P of
+        true -> strip_prefix(Rest, PRest);
+        false -> not_ours
+    end;
+strip_prefix(_, _) -> not_ours.
+
+strip_suffix(Str, Suffix) ->
+    SL = length(Str),
+    XL = length(Suffix),
+    case SL >= XL of
+        true ->
+            Head = take_n_pl(SL - XL, Str),
+            Tail = drop(SL - XL, Str),
+            case Tail =:= Suffix of
+                true -> {ok, Head};
+                false -> not_ours
+            end;
+        false -> not_ours
+    end.
+
+take_n_pl(0, _) -> [];
+take_n_pl(_, []) -> [];
+take_n_pl(N, [H | T]) -> [H | take_n_pl(N - 1, T)].
+
+is_all_digits([]) -> false;
+is_all_digits(Chars) -> all_digits(Chars).
+
+all_digits([]) -> true;
+all_digits([C | Rest]) when C >= $0, C =< $9 -> all_digits(Rest);
+all_digits(_) -> false.
+
+%% read_segments_in_order/4 — fed-prims sorts list_dir alphabetically;
+%% with 6-digit zero-padded names that coincides with numeric order.
+%% But we also accept legacy unpadded names, so sort by index to be
+%% defensive.
+read_segments_in_order(Indices, ActorId, BasePath, Acc) ->
+    Sorted = isort(Indices),
+    read_each(Sorted, ActorId, BasePath, Acc).
+
+read_each([], _, _, Acc) ->
+    {ok, lists:reverse(Acc)};
+read_each([Idx | Rest], ActorId, BasePath, Acc) ->
+    Path = segment_path(ActorId, BasePath, Idx),
+    case try_read_segment(Path) of
+        {ok, Entries} ->
+            read_each(Rest, ActorId, BasePath, [Entries | Acc]);
+        {error, _} = E -> E
+    end.
+
+%% Tiny insertion sort over a small list of integers.
+isort([]) -> [];
+isort([H | T]) -> insert(H, isort(T)).
+insert(X, []) -> [X];
+insert(X, [Y | Rest]) when X =< Y -> [X, Y | Rest];
+insert(X, [Y | Rest]) -> [Y | insert(X, Rest)].
+
+%% segment_path/3 — charlist path to the Idx'th segment file.
+segment_path(ActorId, BasePath, Idx) ->
+    base_chars(BasePath) ++ [$/] ++ atom_to_list(ActorId)
+        ++ [$-] ++ pad_int(Idx, 6) ++ [$., $l, $o, $g].
+
+base_chars(B) when is_binary(B) -> binary_to_list(B);
+base_chars(L) when is_list(L) -> L.
+
+%% Zero-pad an integer to Width digits as a charlist.
+pad_int(N, Width) ->
+    Cs = integer_to_list(N),
+    pad_left(Cs, Width).
+
+pad_left(Cs, Width) ->
+    case length(Cs) >= Width of
+        true -> Cs;
+        false -> pad_left([$0 | Cs], Width)
+    end.
+
+write_segment(Path, Entries) ->
+    Frames = [frame(term_codec:encode(E)) || E <- Entries],
+    file:write_file(Path, list_to_binary(Frames)).
+
+%% frame/1 — prepend 4-byte big-endian length to Payload.
+frame(Payload) when is_binary(Payload) ->
+    L = byte_size(Payload),
+    B3 = (L div 16777216) rem 256,
+    B2 = (L div 65536) rem 256,
+    B1 = (L div 256) rem 256,
+    B0 = L rem 256,
+    [B3, B2, B1, B0, Payload].
+
+try_read_segment(Path) ->
+    case file:read_file(Path) of
+        {ok, Bin} ->
+            try {ok, decode_frames(binary_to_list(Bin), [])}
+            catch
+                throw:Reason -> {error, {corrupt, Reason}};
+                error:Reason -> {error, {corrupt, Reason}}
+            end;
+        {error, enoent} ->
+            {ok, []};
+        {error, R} ->
+            {error, {read, R}}
+    end.
+
+decode_frames([], Acc) ->
+    lists:reverse(Acc);
+decode_frames([B3, B2, B1, B0 | Rest], Acc) ->
+    Len = B3 * 16777216 + B2 * 65536 + B1 * 256 + B0,
+    {Payload, Rest2} = take_n(Len, Rest),
+    case term_codec:decode(list_to_binary(Payload)) of
+        {ok, Term, _} -> decode_frames(Rest2, [Term | Acc]);
+        {error, R} -> throw({decode, R})
+    end;
+decode_frames(_, _) ->
+    throw(truncated_header).
+
+take_n(0, R) -> {[], R};
+take_n(N, [H | T]) ->
+    {Hs, Tl} = take_n(N - 1, T),
+    {[H | Hs], Tl};
+take_n(_, []) ->
+    throw(truncated_body).
+
+%% --- proplist helpers ---
+
+field(K, [{K, V} | _]) -> V;
+field(K, [_ | Rest]) -> field(K, Rest);
+field(_, []) -> erlang:error(badkey).
+
+lookup(K, [{K, V} | _]) -> V;
+lookup(K, [_ | Rest]) -> lookup(K, Rest);
+lookup(_, []) -> undefined.
+
+replace_field(K, V, []) -> [{K, V}];
+replace_field(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+replace_field(K, V, [P | Rest]) -> [P | replace_field(K, V, Rest)].
+
+proplist_get(K, [{K, V} | _], _) -> V;
+proplist_get(K, [_ | Rest], Default) -> proplist_get(K, Rest, Default);
+proplist_get(_, [], Default) -> Default.

next/kernel/log_server.erl

@@ -0,0 +1,85 @@
+-module(log_server).
+-behaviour(gen_server).
+-export([start_link/2, start_link/3,
+         append/2, tip/1, entries/1, replay/3,
+         segments/1, stop/1]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+
+%% Step 3c.b — gen_server in front of `log` that owns a single
+%% per-actor disk-backed log state and serialises concurrent
+%% appenders through `gen_server:call`.
+%%
+%% Architecture: the pure `log` module from Step 3c.a remains the
+%% canonical substrate (open_disk, append, tip, replay, entries,
+%% segments). This wrapper owns one log state per process; every
+%% public op (append/tip/entries/replay/segments) routes through
+%% gen_server:call so that the on-disk segment writer sees one
+%% append at a time, regardless of how many writer processes are
+%% pushing concurrently.
+%%
+%% Port notes carried from Step 5b's registry_server:
+%%   * `gen_server:start_link/2` returns the raw Pid, not `{ok,Pid}`.
+%%   * Spawned processes don't survive across separate
+%%     `erlang-eval-ast` invocations — every concurrency test has
+%%     to start the server, spin writers, join them, and assert all
+%%     within one eval expression.
+%%
+%% API takes the server Pid (not a registered name) so multiple
+%% per-actor servers can coexist without colliding on the registry.
+
+%% --- public API ---
+
+start_link(ActorId, BasePath) ->
+    gen_server:start_link(log_server, [ActorId, BasePath, []]).
+
+start_link(ActorId, BasePath, Opts) ->
+    gen_server:start_link(log_server, [ActorId, BasePath, Opts]).
+
+append(Pid, Activity) ->
+    gen_server:call(Pid, {append, Activity}).
+
+tip(Pid) ->
+    gen_server:call(Pid, tip).
+
+entries(Pid) ->
+    gen_server:call(Pid, entries).
+
+replay(Pid, InitAcc, Fun) ->
+    %% The fold runs server-side so the state stays consistent
+    %% with concurrent writers; the caller's Fun is closed over
+    %% the message and shipped opaque through gen_server:call.
+    gen_server:call(Pid, {replay, InitAcc, Fun}).
+
+segments(Pid) ->
+    gen_server:call(Pid, segments).
+
+stop(Pid) ->
+    gen_server:call(Pid, '$gen_stop').
+
+%% --- gen_server callbacks ---
+
+init([ActorId, BasePath, Opts]) ->
+    case Opts of
+        [] ->
+            {ok, LogState} = log:open_disk(ActorId, BasePath),
+            {ok, LogState};
+        _ ->
+            {ok, LogState} = log:open_disk(ActorId, BasePath, Opts),
+            {ok, LogState}
+    end.
+
+handle_call({append, Activity}, _From, State) ->
+    {ok, NewState, Seq} = log:append(State, Activity),
+    {reply, {ok, Seq}, NewState};
+handle_call(tip, _From, State) ->
+    {reply, log:tip(State), State};
+handle_call(entries, _From, State) ->
+    {reply, log:entries(State), State};
+handle_call({replay, InitAcc, Fun}, _From, State) ->
+    {reply, log:replay(State, InitAcc, Fun), State};
+handle_call(segments, _From, State) ->
+    {reply, log:segments(State), State}.
+
+handle_cast(_, S) -> {noreply, S}.
+
+handle_info(_, S) -> {noreply, S}.

next/kernel/nx_cid.erl

@@ -0,0 +1,24 @@
+-module(nx_cid).
+-export([from_sx/1, to_string/1, from_string/1, equals/2]).
+
+%% The kernel-side CID wrapper. The host BIF `cid:to_string/1` already
+%% produces a canonical CIDv1 (raw codec, sha2-256 multihash) over the
+%% deterministic textual form of any term (er-format-value); we expose
+%% it under the kernel namespace and add the equality + round-trip
+%% helpers the rest of the kernel needs.
+%%
+%% Naming note: the BIF module is `cid`, so we use `nx_cid` to avoid
+%% shadowing. Plans/fed-sx-milestone-1.md §Step 1 spells the file as
+%% `cid.erl`; the briefing flags Erlang snippets as illustrative.
+
+from_sx(V) ->
+    cid:to_string(V).
+
+to_string(Cid) ->
+    Cid.
+
+from_string(S) ->
+    S.
+
+equals(A, B) ->
+    A =:= B.

next/kernel/nx_kernel.erl

@@ -0,0 +1,451 @@
+-module(nx_kernel).
+-behaviour(gen_server).
+
+%% Pure-functional API
+-export([new/0, new/3,
+         add_actor/4, has_actor/2, actors/1, actor_count/1,
+         publish/2, publish/3,
+         bootstrap_actor/4,
+         actor_id/1, log_state/1, log_tip/1,
+         key_spec/1, actor_state/1, projections/1, next_published/1,
+         actor_log_state/2, actor_log_tip/2,
+         actor_inbox_state/2, actor_inbox_tip/2,
+         append_to_actor_inbox/3,
+         actor_key_spec/2, actor_state/2, actor_projections/2,
+         actor_next_published/2, actor_bucket/2,
+         with_projections/2, with_actor_projections/3,
+         next_actor_seq/1]).
+
+%% gen_server API
+-export([start_link/3, publish/1, query/0, log_tip/0,
+         with_projections/1, stop/0,
+         add_actor/3, publish_to/2, log_tip_for/1, log_state_for/1,
+         inbox_tip_for/1, inbox_state_for/1, append_inbox/2,
+         actors/0, state_for/1, bucket_for/1,
+         with_projections_for/2,
+         bootstrap_actor/3]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+
+%% Kernel orchestrator — the long-lived runtime state held by the
+%% running fed-sx instance. Step 1 (m2) refactor: state is now
+%% per-actor bucketed so one kernel hosts any number of actors.
+%%
+%% New state shape (property list):
+%%   [{actors, [{ActorId, ActorBucket}, ...]},
+%%    {next_actor_seq, NextN}]
+%%
+%% ActorBucket = [{key_spec, KS},
+%%                {actor_state, AS},
+%%                {log, L},
+%%                {projections, [Name]},
+%%                {next_published, NextSeq}]
+%%
+%% Legacy single-actor accessors (actor_id/1, key_spec/1, etc.)
+%% continue to read from the first registered actor — keeps every
+%% pre-m2 test passing through bootstrap:start/3.
+%%
+%% next_actor_seq is a monotonic counter handed out to add_actor for
+%% future use (e.g. per-actor URL paths in Step 4). It's not yet
+%% read by the rest of the kernel.
+
+%% ── Pure-functional API ──────────────────────────────────────────
+
+new() ->
+    [{actors, []}, {next_actor_seq, 1}].
+
+new(ActorId, KeySpec, ActorStateProplist) ->
+    {ok, S} = add_actor(ActorId, KeySpec, ActorStateProplist, new()),
+    S.
+
+add_actor(ActorId, KeySpec, AS, State) ->
+    Actors = field(actors, State),
+    case has_keyed(ActorId, Actors) of
+        true ->
+            {error, already_present};
+        false ->
+            {ok, L0} = log:open(ActorId, base_stub()),
+            {ok, I0} = log:open(ActorId, inbox_base_stub()),
+            Bucket = [{key_spec, KeySpec},
+                      {actor_state, AS},
+                      {log, L0},
+                      {actor_inbox, I0},
+                      {projections, []},
+                      {next_published, 1}],
+            Seq = field(next_actor_seq, State),
+            State1 = set(actors, Actors ++ [{ActorId, Bucket}], State),
+            State2 = set(next_actor_seq, Seq + 1, State1),
+            {ok, State2}
+    end.
+
+has_actor(ActorId, State) ->
+    has_keyed(ActorId, field(actors, State)).
+
+actors(State) ->
+    [Id || {Id, _Bucket} <- field(actors, State)].
+
+actor_count(State) ->
+    length(field(actors, State)).
+
+next_actor_seq(State) ->
+    field(next_actor_seq, State).
+
+actor_bucket(ActorId, State) ->
+    find_keyed(ActorId, field(actors, State)).
+
+%% publish/3 — per-actor publish.
+publish(ActorId, Request, State) ->
+    case actor_bucket(ActorId, State) of
+        {error, no_actor} ->
+            {error, no_actor, State};
+        {ok, Bucket} ->
+            P = field(next_published, Bucket),
+            Ctx = [{actor_id,    ActorId},
+                   {published,   P},
+                   {key_spec,    field(key_spec, Bucket)},
+                   {actor_state, field(actor_state, Bucket)},
+                   {log,         field(log, Bucket)},
+                   {projections, field(projections, Bucket)}],
+            case outbox:publish(Request, Ctx) of
+                {ok, Result, NewLog} ->
+                    B1 = set(log, NewLog, Bucket),
+                    B2 = set(next_published, P + 1, B1),
+                    NewState = set_bucket(ActorId, B2, State),
+                    {ok, Result, NewState};
+                {error, Reason, _} ->
+                    {error, Reason, State}
+            end
+    end.
+
+%% publish/2 — legacy single-actor publish; routes to first actor.
+publish(Request, State) ->
+    case actors(State) of
+        [] -> {error, no_actor, State};
+        [First | _] -> publish(First, Request, State)
+    end.
+
+%% bootstrap_actor/4 — register an actor bucket and immediately
+%% publish a Create{Person|Service|Group} as that actor's first
+%% activity. Profile carries the object fields plus :public_keys.
+%% Returns {ok, Result, NewState} where Result has the published
+%% Create's CID, or {error, Reason, State} on validation halt.
+
+bootstrap_actor(ActorId, Profile, KeySpec, State) ->
+    PublicKeys = case field(public_keys, Profile) of
+        nil -> [];
+        KS  -> KS
+    end,
+    AS = [{public_keys, PublicKeys}],
+    case add_actor(ActorId, KeySpec, AS, State) of
+        {ok, State1} ->
+            ActorType = case field(type, Profile) of
+                nil -> person;
+                T   -> T
+            end,
+            Object = [{type, ActorType}] ++ collect_profile_fields(
+                [name, preferredUsername, summary, icon, public_keys],
+                Profile),
+            Request = [{type, create}, {object, Object}],
+            publish(ActorId, Request, State1);
+        {error, Reason} ->
+            {error, Reason, State}
+    end.
+
+collect_profile_fields([], _) -> [];
+collect_profile_fields([F | Rest], Profile) ->
+    case field(F, Profile) of
+        nil -> collect_profile_fields(Rest, Profile);
+        V   -> [{F, V} | collect_profile_fields(Rest, Profile)]
+    end.
+
+with_actor_projections(ActorId, Names, State) ->
+    case actor_bucket(ActorId, State) of
+        {error, no_actor} ->
+            {error, no_actor};
+        {ok, Bucket} ->
+            B1 = set(projections, Names, Bucket),
+            {ok, set_bucket(ActorId, B1, State)}
+    end.
+
+with_projections(Names, State) ->
+    case actors(State) of
+        [] -> State;
+        [First | _] ->
+            {ok, NewState} = with_actor_projections(First, Names, State),
+            NewState
+    end.
+
+%% Per-actor accessors
+
+actor_log_state(ActorId, State) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(log, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+actor_log_tip(ActorId, State) ->
+    case actor_log_state(ActorId, State) of
+        {ok, L}     -> log:tip(L);
+        {error, _}  -> nil
+    end.
+
+actor_inbox_state(ActorId, State) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(actor_inbox, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+actor_inbox_tip(ActorId, State) ->
+    case actor_inbox_state(ActorId, State) of
+        {ok, I}     -> log:tip(I);
+        {error, _}  -> nil
+    end.
+
+%% append_to_actor_inbox/3 — pure-functional inbox append. Mirrors
+%% publish/3's bucket-update shape; the activity is already signed
+%% + validated by the time it lands here (Step 5's pipeline handles
+%% sig verify + replay before this call).
+
+append_to_actor_inbox(ActorId, Activity, State) ->
+    case actor_bucket(ActorId, State) of
+        {error, no_actor} ->
+            {error, no_actor, State};
+        {ok, Bucket} ->
+            Inbox = field(actor_inbox, Bucket),
+            {ok, NewInbox, _Seq} = log:append(Inbox, Activity),
+            B1 = set(actor_inbox, NewInbox, Bucket),
+            {ok, log:tip(NewInbox), set_bucket(ActorId, B1, State)}
+    end.
+
+actor_key_spec(ActorId, State) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(key_spec, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+actor_state(ActorId, State) when is_list(State), is_atom(ActorId) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(actor_state, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+actor_projections(ActorId, State) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(projections, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+actor_next_published(ActorId, State) ->
+    case actor_bucket(ActorId, State) of
+        {ok, B}     -> {ok, field(next_published, B)};
+        {error, _}  -> {error, no_actor}
+    end.
+
+%% Legacy single-actor accessors — read from first bucket. Keeps
+%% every M1 test (smoke_app_pure, bootstrap_start, http_publish,
+%% nx_kernel_server, http_post_format) passing.
+
+actor_id(State) ->
+    case field(actors, State) of
+        []                        -> nil;
+        [{First, _Bucket} | _]    -> First
+    end.
+
+key_spec(State) ->
+    bucket_field(key_spec, State).
+
+actor_state(State) ->
+    bucket_field(actor_state, State).
+
+log_state(State) ->
+    bucket_field(log, State).
+
+log_tip(State) ->
+    log:tip(log_state(State)).
+
+projections(State) ->
+    case bucket_field(projections, State) of
+        nil -> [];
+        Ps  -> Ps
+    end.
+
+next_published(State) ->
+    bucket_field(next_published, State).
+
+%% ── Internal helpers ──────────────────────────────────────────────
+
+base_stub() ->
+    <<98,97,115,101,95,115,116,117,98>>.
+
+%% "inbox_base_stub" — distinct path stub so the in-memory log
+%% module's open/2 returns a fresh log state for the per-actor
+%% inbox bucket. Disk paths will namespace on this once Step 3b
+%% on-disk persistence is reactivated for inbox buckets.
+inbox_base_stub() ->
+    <<105,110,98,111,120,95,115,116,117,98>>.
+
+bucket_field(Key, State) ->
+    case field(actors, State) of
+        []                        -> nil;
+        [{_First, Bucket} | _]    -> field(Key, Bucket)
+    end.
+
+set_bucket(ActorId, NewBucket, State) ->
+    Actors = field(actors, State),
+    NewActors = set_keyed(ActorId, NewBucket, Actors),
+    set(actors, NewActors, State).
+
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)];
+set_keyed(_, _, []) -> [].
+
+has_keyed(_, []) -> false;
+has_keyed(K, [{K, _} | _]) -> true;
+has_keyed(K, [_ | Rest]) -> has_keyed(K, Rest).
+
+find_keyed(_, []) -> {error, no_actor};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+field(K, [{K, V} | _]) -> V;
+field(K, [_ | Rest]) -> field(K, Rest);
+field(_, []) -> nil.
+
+set(K, V, []) -> [{K, V}];
+set(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set(K, V, [P | Rest]) -> [P | set(K, V, Rest)].
+
+%% ── gen_server wrapper ──────────────────────────────────────────
+%%
+%% Mirrors the registry / projection gen_server patterns from
+%% Steps 5b and 7b. Same port quirks: raw Pid return, no `?MODULE`
+%% macro, spawned processes don't persist across separate
+%% erlang-eval-ast calls — tests inline start_link with operations.
+%%
+%% Step 1b (m2) adds multi-actor gen_server calls:
+%% add_actor/3, publish_to/2, log_tip_for/1, actors/0, state_for/1,
+%% with_projections_for/2 — all delegating to the pure-functional
+%% bucket APIs. Existing single-actor calls (publish/1, log_tip/0,
+%% with_projections/1) continue to route through bucket 0.
+
+start_link(ActorId, KeySpec, ActorStateProplist) ->
+    Pid = gen_server:start_link(nx_kernel,
+            [ActorId, KeySpec, ActorStateProplist]),
+    erlang:register(nx_kernel, Pid),
+    Pid.
+
+stop() ->
+    R = gen_server:call(nx_kernel, '$gen_stop'),
+    erlang:unregister(nx_kernel),
+    R.
+
+publish(Request) ->
+    gen_server:call(nx_kernel, {publish, Request}).
+
+query() ->
+    gen_server:call(nx_kernel, get_state).
+
+log_tip() ->
+    gen_server:call(nx_kernel, get_log_tip).
+
+with_projections(Names) ->
+    gen_server:call(nx_kernel, {set_projections, Names}).
+
+%% Step 1b — multi-actor gen_server calls.
+
+add_actor(ActorId, KeySpec, AS) ->
+    gen_server:call(nx_kernel, {add_actor, ActorId, KeySpec, AS}).
+
+publish_to(ActorId, Request) ->
+    gen_server:call(nx_kernel, {publish_to, ActorId, Request}).
+
+log_tip_for(ActorId) ->
+    gen_server:call(nx_kernel, {log_tip_for, ActorId}).
+
+log_state_for(ActorId) ->
+    gen_server:call(nx_kernel, {log_state_for, ActorId}).
+
+inbox_tip_for(ActorId) ->
+    gen_server:call(nx_kernel, {inbox_tip_for, ActorId}).
+
+inbox_state_for(ActorId) ->
+    gen_server:call(nx_kernel, {inbox_state_for, ActorId}).
+
+append_inbox(ActorId, Activity) ->
+    gen_server:call(nx_kernel, {append_inbox, ActorId, Activity}).
+
+actors() ->
+    gen_server:call(nx_kernel, get_actors).
+
+state_for(ActorId) ->
+    gen_server:call(nx_kernel, {state_for, ActorId}).
+
+bucket_for(ActorId) ->
+    gen_server:call(nx_kernel, {bucket_for, ActorId}).
+
+with_projections_for(ActorId, Names) ->
+    gen_server:call(nx_kernel, {set_projections_for, ActorId, Names}).
+
+bootstrap_actor(ActorId, Profile, KeySpec) ->
+    gen_server:call(nx_kernel, {bootstrap_actor, ActorId, Profile, KeySpec}).
+
+%% gen_server callbacks
+
+init([ActorId, KeySpec, AS]) ->
+    {ok, new(ActorId, KeySpec, AS)}.
+
+handle_call({publish, Request}, _From, State) ->
+    case publish(Request, State) of
+        {ok, Result, NewState} ->
+            {reply, {ok, Result}, NewState};
+        {error, Reason, SameState} ->
+            {reply, {error, Reason}, SameState}
+    end;
+handle_call(get_state, _From, State) ->
+    {reply, State, State};
+handle_call(get_log_tip, _From, State) ->
+    {reply, log_tip(State), State};
+handle_call({set_projections, Names}, _From, State) ->
+    {reply, ok, with_projections(Names, State)};
+handle_call({add_actor, ActorId, KeySpec, AS}, _From, State) ->
+    case add_actor(ActorId, KeySpec, AS, State) of
+        {ok, NewState}      -> {reply, ok, NewState};
+        {error, Reason}     -> {reply, {error, Reason}, State}
+    end;
+handle_call({publish_to, ActorId, Request}, _From, State) ->
+    case publish(ActorId, Request, State) of
+        {ok, Result, NewState}      -> {reply, {ok, Result}, NewState};
+        {error, Reason, SameState}  -> {reply, {error, Reason}, SameState}
+    end;
+handle_call({log_tip_for, ActorId}, _From, State) ->
+    {reply, actor_log_tip(ActorId, State), State};
+handle_call({log_state_for, ActorId}, _From, State) ->
+    {reply, actor_log_state(ActorId, State), State};
+handle_call({inbox_tip_for, ActorId}, _From, State) ->
+    {reply, actor_inbox_tip(ActorId, State), State};
+handle_call({inbox_state_for, ActorId}, _From, State) ->
+    {reply, actor_inbox_state(ActorId, State), State};
+handle_call({append_inbox, ActorId, Activity}, _From, State) ->
+    case append_to_actor_inbox(ActorId, Activity, State) of
+        {ok, Tip, NewState}     -> {reply, {ok, Tip}, NewState};
+        {error, Reason, Same}   -> {reply, {error, Reason}, Same}
+    end;
+handle_call(get_actors, _From, State) ->
+    {reply, actors(State), State};
+handle_call({state_for, ActorId}, _From, State) ->
+    {reply, actor_state(ActorId, State), State};
+handle_call({bucket_for, ActorId}, _From, State) ->
+    {reply, actor_bucket(ActorId, State), State};
+handle_call({set_projections_for, ActorId, Names}, _From, State) ->
+    case with_actor_projections(ActorId, Names, State) of
+        {ok, NewState}      -> {reply, ok, NewState};
+        {error, Reason}     -> {reply, {error, Reason}, State}
+    end;
+handle_call({bootstrap_actor, ActorId, Profile, KeySpec}, _From, State) ->
+    case bootstrap_actor(ActorId, Profile, KeySpec, State) of
+        {ok, Result, NewState}      -> {reply, {ok, Result}, NewState};
+        {error, Reason, SameState}  -> {reply, {error, Reason}, SameState}
+    end.
+
+handle_cast(_, S) -> {noreply, S}.
+
+handle_info(_, S) -> {noreply, S}.

next/kernel/outbox.erl

@@ -0,0 +1,188 @@
+-module(outbox).
+-export([construct/4, sign/2, cid_of/1, publish/2]).
+
+%% Outbox envelope construction + signing per design §3.1.
+%%
+%% construct/4 builds an unsigned activity envelope from caller-supplied
+%% (Type, ActorId, Published, Object). The envelope's `:id` field is
+%% derived from the host `cid:to_string` BIF over a skeleton tag, so
+%% recipients can address the activity by its content hash. The
+%% returned property list is the canonical key-sorted form that
+%% `envelope:canonical_bytes/1` operates on.
+%%
+%% sign/2 takes the unsigned envelope plus a KeySpec proplist that
+%% mirrors a `public_keys` entry: `[{key_id, _}, {algorithm, _},
+%% {value, KeyMaterial}]`. It computes the v1 HMAC stand-in
+%% `crypto:hash(sha256, <<KeyMaterial/binary, CanonicalBytes/binary>>)`
+%% — the same scheme `envelope:verify_signature/2` checks — and
+%% appends a `:signature` pair.
+%%
+%% Real Ed25519 / RSA signing arrives in milestone 2 once
+%% `crypto:sign_ed25519/2` BIFs land; the API shape doesn't change.
+
+%% construct/4 — Type and ActorId are atoms; Published is an
+%% integer timestamp the caller supplies (no clock BIF in this
+%% port; the HTTP layer / outbox:publish caller injects it).
+%% Object can be any term, including a property list of inner
+%% fields.
+construct(Type, ActorId, Published, Object) ->
+    Skeleton = [{actor, ActorId},
+                {object, Object},
+                {published, Published},
+                {type, Type}],
+    Id = cid:to_string({activity_envelope, Skeleton}),
+    [{actor, ActorId},
+     {id, Id},
+     {object, Object},
+     {published, Published},
+     {type, Type}].
+
+%% sign/2 — KeySpec carries key_id, algorithm, value (key material).
+sign(Envelope, KeySpec) ->
+    {ok, KeyId} = envelope:get_field(key_id, KeySpec),
+    {ok, Alg}   = envelope:get_field(algorithm, KeySpec),
+    {ok, KM}    = envelope:get_field(value, KeySpec),
+    CB = envelope:canonical_bytes(Envelope),
+    SigValue = crypto:hash(sha256, <<KM/binary, CB/binary>>),
+    Sig = [{algorithm, Alg}, {key_id, KeyId}, {value, SigValue}],
+    Envelope ++ [{signature, Sig}].
+
+%% cid_of/1 — extract the :id field from a constructed envelope.
+%% Convenience for callers that don't want to thread the CID
+%% separately when both the envelope and its ID matter.
+cid_of(Envelope) ->
+    {ok, Id} = envelope:get_field(id, Envelope),
+    Id.
+
+%% publish/2 — the outbound activity pipeline orchestrator.
+%%
+%% Request shape:   [{type, T}, {object, O}]
+%% Context shape:   [{actor_id, A}, {published, P}, {key_spec, KS},
+%%                   {actor_state, AS}, {log, L}]
+%%
+%% Returns:
+%%   {ok, [{cid, Cid}, {activity, Signed}], NewLog}   — happy path
+%%   {error, Reason, LogState}                         — validation halted
+%%
+%% Stages run in order: envelope shape, signature, replay. The
+%% replay check uses the log state pre-append, so if the caller
+%% publishes the same Request twice with the same Published
+%% timestamp the second call halts with {error, replay, _}.
+%%
+%% Projection-scheduler dispatch (the async fold the design calls
+%% for) is deferred to Step 7 — once the projection gen_server
+%% exists, this function will broadcast `Signed` to it.
+
+publish(Request, Context) ->
+    Type      = envelope_field(type, Request),
+    Object    = envelope_field(object, Request),
+    ActorId   = envelope_field(actor_id, Context),
+    Published = envelope_field(published, Context),
+    KeySpec   = envelope_field(key_spec, Context),
+    ActorState = envelope_field(actor_state, Context),
+    LogState   = envelope_field(log, Context),
+    Unsigned = construct(Type, ActorId, Published, Object),
+    Signed = sign(Unsigned, KeySpec),
+    Stages = [
+        fun (A) -> pipeline:stage_envelope(A) end,
+        pipeline:stage_signature(ActorState),
+        pipeline:stage_replay(LogState)
+    ],
+    case pipeline:run_stages(Signed, Stages) of
+        ok ->
+            {ok, NewLog, _Seq} = log:append(LogState, Signed),
+            broadcast(Signed, envelope_field(projections, Context)),
+            DeliverySet = compute_delivery_set(Request, Signed, Context),
+            dispatch_deliveries(Signed, DeliverySet, Context),
+            Result = [{cid, cid_of(Signed)},
+                      {activity, Signed},
+                      {delivery_set, DeliverySet}],
+            {ok, Result, NewLog};
+        {error, Reason} ->
+            {error, Reason, LogState}
+    end.
+
+%% dispatch_deliveries/3 — Step 8d. For each ActorId in the
+%% delivery_set, enqueue the signed activity onto the matching
+%% delivery_worker if the worker is registered under that atom.
+%% Missing workers are silently skipped — lazy creation belongs
+%% to the kernel manager (later in Step 8). The Context
+%% `:dispatch_deliveries` field gates the call so existing
+%% outbox callers that don't yet care about delivery (e.g. all of
+%% M1's tests) stay back-compat.
+%%
+%% No-op when:
+%%   - :dispatch_deliveries is absent or not the atom true
+%%   - delivery_set is []
+%%   - the per-peer worker isn't registered (whereis returns undefined)
+
+dispatch_deliveries(Activity, DeliverySet, Context) ->
+    case envelope_field(dispatch_deliveries, Context) of
+        true -> enqueue_each(Activity, DeliverySet);
+        _    -> ok
+    end.
+
+enqueue_each(_Activity, []) -> ok;
+enqueue_each(Activity, [PeerId | Rest]) when is_atom(PeerId) ->
+    case erlang:whereis(PeerId) of
+        undefined -> enqueue_each(Activity, Rest);
+        _         ->
+            delivery_worker:enqueue(PeerId, Activity),
+            enqueue_each(Activity, Rest)
+    end;
+enqueue_each(Activity, [_ | Rest]) ->
+    enqueue_each(Activity, Rest).
+
+%% compute_delivery_set/3 — Step 7c. Pulls the audience-resolved
+%% recipient list off the Request's `:to` / `:cc` fields (the
+%% envelope itself doesn't carry them — construct/4 only takes
+%% type / actor / published / object). Context's optional
+%% `:follower_graph` field carries a follower_graph state for
+%% `public` / `followers` audience expansion; absent -> empty graph,
+%% so explicit `:to` / `:cc` lists still resolve. Synthesises a
+%% recipient-shaped envelope from Request + Signed so the existing
+%% delivery:delivery_set/3 (which reads `:actor`, `:to`, `:cc`) can
+%% process it as-is.
+%%
+%% Step 8's delivery-queue worker reads `{delivery_set, [ActorId, ...]}`
+%% off the publish result and routes one HTTP POST per entry.
+
+compute_delivery_set(Request, Signed, Context) ->
+    Graph = case envelope_field(follower_graph, Context) of
+        nil -> follower_graph:new();
+        G   -> G
+    end,
+    Recipients = recipients_envelope(Request, Signed),
+    delivery:delivery_set(Recipients, [], Graph).
+
+recipients_envelope(Request, Signed) ->
+    Base = case envelope:get_field(actor, Signed) of
+        {ok, A} -> [{actor, A}];
+        _       -> []
+    end,
+    To = case envelope:get_field(to, Request) of
+        {ok, T} -> [{to, T}];
+        _       -> []
+    end,
+    Cc = case envelope:get_field(cc, Request) of
+        {ok, C} -> [{cc, C}];
+        _       -> []
+    end,
+    Base ++ To ++ Cc.
+
+%% broadcast/2 — fire-and-forget cast to each named projection.
+%% Missing/nil/empty list is a no-op; the publish API does not
+%% require projections to exist. Activity is the post-sign Signed
+%% envelope (same value that landed in the log).
+broadcast(_Activity, nil) -> ok;
+broadcast(_Activity, []) -> ok;
+broadcast(Activity, [Name | Rest]) ->
+    projection:async_fold(Name, Activity),
+    broadcast(Activity, Rest).
+
+envelope_field(K, PL) ->
+    case envelope:get_field(K, PL) of
+        {ok, V}   -> V;
+        not_found -> nil
+    end.
+

next/kernel/peer_actors.erl

@@ -0,0 +1,140 @@
+-module(peer_actors).
+-export([new/0, lookup/2, store/3, evict/2, peers/1,
+         lookup_or_fetch/3,
+         start_link/0, start_link/1, stop/0,
+         lookup_srv/1, store_srv/2, lookup_or_fetch_srv/2,
+         peers_srv/0, evict_srv/1]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+-behaviour(gen_server).
+
+%% Peer-actors cache. On first inbound from a new peer, the
+%% federation layer needs the peer's `:public_keys` (and eventually
+%% other actor-doc fields) to verify the inbound signature. Fetching
+%% the peer's actor doc on every inbound would be wasteful, so we
+%% cache the peer-AS keyed by ActorId atom. Per design §13.6 stale-
+%% key invalidation defers to v3 — for v2 entries are TTL-free.
+%%
+%% State shape (pure-functional):
+%%   [{PeerActorId, PeerActorState}, ...]
+%%
+%% PeerActorState is the same shape that envelope:verify_signature/2
+%% reads — a proplist with :public_keys (a list of key proplists).
+%%
+%% lookup_or_fetch/3 is the load-bearing entry point: a miss invokes
+%% the caller-supplied FetchFn (1-arity, takes PeerActorId, returns
+%% {ok, PeerAS} | {error, Reason}). The cache stores successful
+%% fetches; errors do NOT poison the cache so the caller can retry.
+%%
+%% gen_server wrapper exposes the same API for the http inbox
+%% handler. Tests inline start_link with operations (same port quirks
+%% as registry / projection / nx_kernel).
+
+%% ── Pure-functional API ─────────────────────────────────────────
+
+new() -> [].
+
+lookup(PeerId, State) ->
+    case find_keyed(PeerId, State) of
+        {ok, PeerAS} -> {ok, PeerAS};
+        {error, _}   -> not_found
+    end.
+
+store(PeerId, PeerAS, State) ->
+    set_keyed(PeerId, PeerAS, State).
+
+evict(PeerId, State) ->
+    delete_keyed(PeerId, State).
+
+peers(State) -> [Id || {Id, _AS} <- State].
+
+%% lookup_or_fetch/3 — cache hit returns {ok, PeerAS, State}
+%% unchanged. Cache miss calls FetchFn; success path stores and
+%% returns {ok, PeerAS, NewState}; failure returns {error, Reason,
+%% State} so the caller knows the cache state and can retry on
+%% transient errors.
+
+lookup_or_fetch(PeerId, FetchFn, State) ->
+    case find_keyed(PeerId, State) of
+        {ok, PeerAS} -> {ok, PeerAS, State};
+        {error, _}   ->
+            case FetchFn(PeerId) of
+                {ok, PeerAS}    -> {ok, PeerAS, store(PeerId, PeerAS, State)};
+                {error, Reason} -> {error, Reason, State};
+                Other           -> {error, {bad_fetch_return, Other}, State}
+            end
+    end.
+
+%% ── gen_server wrapper ──────────────────────────────────────────
+%%
+%% Mirrors registry / projection / nx_kernel patterns. Registered
+%% name `peer_actors` so callers (http_server inbox handler) can
+%% find it without threading the Pid through Cfg.
+
+start_link() ->
+    start_link([]).
+
+start_link(InitialState) ->
+    Pid = gen_server:start_link(peer_actors, [InitialState]),
+    erlang:register(peer_actors, Pid),
+    Pid.
+
+stop() ->
+    R = gen_server:call(peer_actors, '$gen_stop'),
+    erlang:unregister(peer_actors),
+    R.
+
+lookup_srv(PeerId) ->
+    gen_server:call(peer_actors, {lookup, PeerId}).
+
+store_srv(PeerId, PeerAS) ->
+    gen_server:call(peer_actors, {store, PeerId, PeerAS}).
+
+%% lookup_or_fetch_srv/2 — same shape as the pure form. FetchFn must
+%% be a 1-arity fun. Reply is {ok, PeerAS} on hit-or-fetched,
+%% {error, Reason} on fetch failure.
+
+lookup_or_fetch_srv(PeerId, FetchFn) ->
+    gen_server:call(peer_actors, {lookup_or_fetch, PeerId, FetchFn}).
+
+peers_srv() ->
+    gen_server:call(peer_actors, get_peers).
+
+evict_srv(PeerId) ->
+    gen_server:call(peer_actors, {evict, PeerId}).
+
+%% gen_server callbacks
+
+init([InitialState]) ->
+    {ok, InitialState}.
+
+handle_call({lookup, PeerId}, _From, State) ->
+    {reply, lookup(PeerId, State), State};
+handle_call({store, PeerId, PeerAS}, _From, State) ->
+    {reply, ok, store(PeerId, PeerAS, State)};
+handle_call({lookup_or_fetch, PeerId, FetchFn}, _From, State) ->
+    case lookup_or_fetch(PeerId, FetchFn, State) of
+        {ok, PeerAS, NewState}      -> {reply, {ok, PeerAS}, NewState};
+        {error, Reason, SameState}  -> {reply, {error, Reason}, SameState}
+    end;
+handle_call(get_peers, _From, State) ->
+    {reply, peers(State), State};
+handle_call({evict, PeerId}, _From, State) ->
+    {reply, ok, evict(PeerId, State)}.
+
+handle_cast(_, S) -> {noreply, S}.
+
+handle_info(_, S) -> {noreply, S}.
+
+%% ── Internal helpers ────────────────────────────────────────────
+
+find_keyed(_, []) -> {error, not_found};
+find_keyed(K, [{K, V} | _]) -> {ok, V};
+find_keyed(K, [_ | Rest]) -> find_keyed(K, Rest).
+
+set_keyed(K, V, []) -> [{K, V}];
+set_keyed(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_keyed(K, V, [P | Rest]) -> [P | set_keyed(K, V, Rest)].
+
+delete_keyed(_, []) -> [];
+delete_keyed(K, [{K, _} | Rest]) -> Rest;
+delete_keyed(K, [P | Rest]) -> [P | delete_keyed(K, Rest)].

next/kernel/pipeline.erl

@@ -0,0 +1,167 @@
+-module(pipeline).
+-export([run_stages/2,
+         validate_inbound/1, validate_inbound/3,
+         validate_outbound/1,
+         inbound_stages/0, inbound_stages/2, outbound_stages/0,
+         stage_envelope/1,
+         stage_signature/1, stage_signature/2,
+         stage_replay/1, stage_replay/2,
+         stage_schema/1, stage_schema/2]).
+
+%% Validation pipeline per design §14.
+%%
+%% A stage is a 1-arity fun `(Activity) -> ok | {error, Reason}`.
+%% The driver folds the activity through the stage list, halting
+%% on the first error. The pure-functional driver itself takes a
+%% stage list directly so tests can inject ad-hoc stage sequences
+%% without depending on the bundled inbound/outbound lists.
+%%
+%% Inbound pipeline (full set per design §14): envelope, signature,
+%% replay, audience, activity_schema, object_schema, content_validators,
+%% capabilities, trust. Outbound is a subset (no replay, no trust;
+%% auth handled at the HTTP layer).
+%%
+%% This sub-deliverable (6a) wires only the driver and the empty
+%% stage lists. Concrete stages land in 6b-6c.
+
+run_stages(_Activity, []) -> ok;
+run_stages(Activity, [Stage | Rest]) ->
+    Result = Stage(Activity),
+    case Result of
+        ok         -> run_stages(Activity, Rest);
+        {error, _} -> Result
+    end.
+
+validate_inbound(Activity) ->
+    run_stages(Activity, inbound_stages()).
+
+%% validate_inbound/3 — Step 5b federation inbound pipeline.
+%%
+%% Activity:      the signed envelope as received from the peer.
+%% PeerActorState: the peer's actor-state proplist carrying
+%%                 :public_keys for signature verification. Caller
+%%                 resolves this — for v2 it's either pre-populated
+%%                 from a peer-actors cache (Step 5c) or known from
+%%                 a two-instance test fixture.
+%% InboxLog:      the receiving actor's :actor_inbox log state.
+%%                Used by stage_replay to reject duplicate :id.
+%%
+%% Stages (per design §13.2 + §14):
+%%   stage_envelope                 — shape check
+%%   stage_signature(PeerAS)        — peer sig verify
+%%   stage_replay(InboxLog)         — replay defence against
+%%                                    receiving actor's inbox
+%%
+%% Returns ok | {error, Reason}. The driver halts on first failure.
+%% Audience / schema / capabilities / trust stages defer to v3.
+
+validate_inbound(Activity, PeerActorState, InboxLog) ->
+    run_stages(Activity, inbound_stages(PeerActorState, InboxLog)).
+
+validate_outbound(Activity) ->
+    run_stages(Activity, outbound_stages()).
+
+inbound_stages() ->
+    [fun (A) -> stage_envelope(A) end].
+
+%% inbound_stages/2 — the full ordered stage list for federation
+%% inbound (envelope -> peer sig -> replay against inbox).
+
+inbound_stages(PeerActorState, InboxLog) ->
+    [fun (A) -> stage_envelope(A) end,
+     stage_signature(PeerActorState),
+     stage_replay(InboxLog)].
+
+outbound_stages() ->
+    [fun (A) -> stage_envelope(A) end].
+
+%% ── Concrete stages ─────────────────────────────────────────────
+
+%% stage_envelope/1 — wrap envelope:validate_shape/1. The pipeline
+%% driver expects ok | {error, R}; validate_shape returns exactly
+%% that, so delegation is direct.
+stage_envelope(Activity) ->
+    envelope:validate_shape(Activity).
+
+%% stage_signature/2 — direct (Activity, ActorState) check. Wraps
+%% envelope:verify_signature/2 from Step 2c. Useful for tests and
+%% for callers that already have ActorState in scope.
+stage_signature(Activity, ActorState) ->
+    envelope:verify_signature(Activity, ActorState).
+
+%% stage_signature/1 — factory: takes the ActorState and returns a
+%% 1-arity stage fun the pipeline driver can fold. This is how
+%% signature checking gets composed into a stage list at runtime
+%% (the static `inbound_stages/0` list omits it precisely because
+%% ActorState isn't available at static-list build time).
+stage_signature(ActorState) ->
+    fun (Activity) -> envelope:verify_signature(Activity, ActorState) end.
+
+%% stage_replay/2 — checks the in-memory log for an existing
+%% activity with the same :id. Returns ok if the activity is new,
+%% `{error, replay}` if the log already carries it, `{error, no_id}`
+%% if the activity has no :id field. The check is linear scan of
+%% log entries; the projection scheduler (Step 7) will eventually
+%% maintain a CID index that turns this into O(1).
+stage_replay(Activity, LogState) ->
+    case envelope:get_field(id, Activity) of
+        not_found -> {error, no_id};
+        {ok, Id} ->
+            case log_has_id(Id, log:entries(LogState)) of
+                true  -> {error, replay};
+                false -> ok
+            end
+    end.
+
+stage_replay(LogState) ->
+    fun (Activity) -> stage_replay(Activity, LogState) end.
+
+log_has_id(_, []) -> false;
+log_has_id(Id, [Act | Rest]) ->
+    case envelope:get_field(id, Act) of
+        {ok, Id} -> true;
+        _        -> log_has_id(Id, Rest)
+    end.
+
+%% stage_schema/2 — validates the activity's :object against the
+%% schema registered for its :type. SchemaLookup is a caller-
+%% supplied fun (Type) -> {ok, SchemaFn} | not_found; SchemaFn is
+%% itself a fun (Object) -> bool. Returns:
+%%   ok                          when the schema accepts the object
+%%   {error, no_type}            when the activity has no :type
+%%   {error, schema_mismatch}    when SchemaFn returned false
+%%
+%% Open-world default: an unregistered Type returns ok so the
+%% pipeline doesn't block activities the kernel hasn't yet learned
+%% about. Tightening to strict-world happens later in milestone 2.
+%%
+%% Activities with no :object skip the schema check (some verbs
+%% legitimately carry no object).
+%%
+%% The Erlang-fun shape is the substrate-friendly stand-in for the
+%% SX-source :schema bodies stored in the genesis bundle. Once an
+%% SX-source eval bridge exists, the same stage shape will dispatch
+%% through it instead — no API change.
+stage_schema(Activity, SchemaLookup) ->
+    case envelope:get_field(type, Activity) of
+        not_found -> {error, no_type};
+        {ok, Type} ->
+            case SchemaLookup(Type) of
+                not_found -> ok;
+                {ok, SchemaFn} ->
+                    check_object_schema(Activity, SchemaFn)
+            end
+    end.
+
+check_object_schema(Activity, SchemaFn) ->
+    case envelope:get_field(object, Activity) of
+        not_found -> ok;
+        {ok, Obj} ->
+            case SchemaFn(Obj) of
+                true -> ok;
+                false -> {error, schema_mismatch}
+            end
+    end.
+
+stage_schema(SchemaLookup) ->
+    fun (Activity) -> stage_schema(Activity, SchemaLookup) end.

next/kernel/projection.erl

@@ -0,0 +1,97 @@
+-module(projection).
+-behaviour(gen_server).
+-export([new/2, new/3, fold_activity/2, replay/2,
+         name/1, state/1, fold_fn/1]).
+-export([start_link/3, async_fold/2, query/1, stop/1]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+
+%% Pure-functional projection driver per design §10.
+%%
+%% A projection is a property list:
+%%   [{name, atom}, {state, term}, {fold, fun}]
+%%
+%% The fold function is `fun (Activity, State) -> NewState`. v1
+%% uses Erlang funs as the fold body — the genesis bundle's SX
+%% `:fold` bodies are stored as binaries; an SX-source eval
+%% bridge will plug them into the same projection record once
+%% it lands (Step 7d). For now, callers supply Erlang funs
+%% directly when constructing a projection.
+%%
+%% `replay/2` is the cold-start primitive: fold an activity
+%% list (e.g. `log:entries/1`) through the projection from its
+%% initial state.
+
+new(Name, InitialState) ->
+    new(Name, InitialState, fun (_Activity, S) -> S end).
+
+new(Name, InitialState, FoldFn) ->
+    [{name, Name}, {state, InitialState}, {fold, FoldFn}].
+
+fold_activity(Proj, Activity) ->
+    Fn  = fold_fn(Proj),
+    S0  = state(Proj),
+    S1  = Fn(Activity, S0),
+    set_field(state, S1, Proj).
+
+replay(Proj, Activities) ->
+    fold_each(Proj, Activities).
+
+fold_each(Proj, []) -> Proj;
+fold_each(Proj, [A | Rest]) ->
+    fold_each(fold_activity(Proj, A), Rest).
+
+%% Accessors
+
+name(Proj)    -> field(name, Proj).
+state(Proj)   -> field(state, Proj).
+fold_fn(Proj) -> field(fold, Proj).
+
+%% Internal
+
+field(K, [{K, V} | _]) -> V;
+field(K, [_ | Rest]) -> field(K, Rest);
+field(_, []) -> erlang:error(badkey).
+
+set_field(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+set_field(K, V, [P | Rest]) -> [P | set_field(K, V, Rest)];
+set_field(K, V, []) -> [{K, V}].
+
+%% ── Step 7b: gen_server wrapper ─────────────────────────────────
+%%
+%% Each projection runs in its own gen_server, registered under the
+%% projection's Name atom. `async_fold/2` casts an activity into the
+%% process; `query/1` synchronously fetches the current state.
+%%
+%% Port notes (mirroring Step 5b on the registry): `gen_server:start_link`
+%% returns the raw Pid; `?MODULE` macro is unsupported; spawned
+%% processes don't survive across separate `erlang-eval-ast` calls
+%% so tests must inline start_link with their operations.
+
+start_link(Name, InitialState, FoldFn) ->
+    Pid = gen_server:start_link(projection, [Name, InitialState, FoldFn]),
+    erlang:register(Name, Pid),
+    Pid.
+
+async_fold(Name, Activity) ->
+    gen_server:cast(Name, {fold, Activity}).
+
+query(Name) ->
+    gen_server:call(Name, get_state).
+
+stop(Name) ->
+    R = gen_server:call(Name, '$gen_stop'),
+    erlang:unregister(Name),
+    R.
+
+%% gen_server callbacks
+
+init([Name, InitialState, FoldFn]) ->
+    {ok, new(Name, InitialState, FoldFn)}.
+
+handle_call(get_state, _From, Proj) ->
+    {reply, state(Proj), Proj}.
+
+handle_cast({fold, Activity}, Proj) ->
+    {noreply, fold_activity(Proj, Activity)}.
+
+handle_info(_, Proj) -> {noreply, Proj}.

next/kernel/registry.erl

@@ -0,0 +1,120 @@
+-module(registry).
+-behaviour(gen_server).
+-export([new/0, kinds/0, register/4, lookup/3, list/2]).
+-export([start_link/0, register/3, lookup/2, list/1, stop/0]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2]).
+
+%% Pure-functional registry for the seven bootstrap kinds.
+%%
+%% State is a property list keyed by kind atom; each kind's value
+%% is itself a property list of {Name, Entry} pairs. Entry is
+%% opaque — typically a proplist with :cid, :schema, :semantics,
+%% :supersedes fields, but the registry doesn't enforce that here.
+%%
+%% A gen_server wrapper (Step 5b) will own the global registry
+%% process; the pure functions in this module remain the canonical
+%% API and are usable for tests and for offline projection-replay.
+%%
+%% Return shapes:
+%%   new/0            -> State
+%%   kinds/0          -> [Atom, ...]
+%%   register/4       -> {ok, NewState} | {error, unknown_kind}
+%%   lookup/3         -> {ok, Entry} | not_found | {error, unknown_kind}
+%%   list/2           -> [{Name, Entry}, ...] | {error, unknown_kind}
+
+new() -> [].
+
+kinds() ->
+    [activity_types, object_types, projections,
+     validators, codecs, sig_suites, audience].
+
+register(Kind, Name, Entry, State) ->
+    case is_valid_kind(Kind) of
+        false -> {error, unknown_kind};
+        true ->
+            Entries = kind_entries(Kind, State),
+            Updated = put_pair(Name, Entry, Entries),
+            {ok, set_kind_entries(Kind, Updated, State)}
+    end.
+
+lookup(Kind, Name, State) ->
+    case is_valid_kind(Kind) of
+        false -> {error, unknown_kind};
+        true ->
+            find_pair(Name, kind_entries(Kind, State))
+    end.
+
+list(Kind, State) ->
+    case is_valid_kind(Kind) of
+        false -> {error, unknown_kind};
+        true  -> kind_entries(Kind, State)
+    end.
+
+%% ── Internal ────────────────────────────────────────────────────
+
+is_valid_kind(K) -> lists:member(K, kinds()).
+
+kind_entries(Kind, State) ->
+    case find_pair(Kind, State) of
+        not_found -> [];
+        {ok, V}   -> V
+    end.
+
+set_kind_entries(Kind, Entries, State) ->
+    put_pair(Kind, Entries, State).
+
+put_pair(K, V, []) -> [{K, V}];
+put_pair(K, V, [{K, _} | Rest]) -> [{K, V} | Rest];
+put_pair(K, V, [P | Rest]) -> [P | put_pair(K, V, Rest)].
+
+find_pair(_, []) -> not_found;
+find_pair(K, [{K, V} | _]) -> {ok, V};
+find_pair(K, [_ | Rest]) -> find_pair(K, Rest).
+
+%% ── Step 5b: gen_server wrapper ─────────────────────────────────
+%%
+%% The named process owns the registry state; concurrent readers
+%% and writers serialize through gen_server:call. The pure /3 and
+%% /4 functions remain available for offline projection-replay and
+%% for tests that don't need a process at all.
+%%
+%% Port notes: gen_server:start_link returns the raw Pid (not
+%% `{ok, Pid}` as in OTP). `?MODULE` macro is unsupported here, so
+%% the registered name is the literal `registry` atom in every call.
+
+start_link() ->
+    Pid = gen_server:start_link(registry, []),
+    erlang:register(registry, Pid),
+    Pid.
+
+stop() ->
+    R = gen_server:call(registry, '$gen_stop'),
+    erlang:unregister(registry),
+    R.
+
+register(Kind, Name, Entry) ->
+    gen_server:call(registry, {register, Kind, Name, Entry}).
+
+lookup(Kind, Name) ->
+    gen_server:call(registry, {lookup, Kind, Name}).
+
+list(Kind) ->
+    gen_server:call(registry, {list, Kind}).
+
+%% gen_server callbacks
+
+init(_) -> {ok, new()}.
+
+handle_call({register, Kind, Name, Entry}, _From, State) ->
+    case register(Kind, Name, Entry, State) of
+        {ok, NewState} -> {reply, ok, NewState};
+        {error, R}     -> {reply, {error, R}, State}
+    end;
+handle_call({lookup, Kind, Name}, _From, State) ->
+    {reply, lookup(Kind, Name, State), State};
+handle_call({list, Kind}, _From, State) ->
+    {reply, list(Kind, State), State}.
+
+handle_cast(_, S) -> {noreply, S}.
+
+handle_info(_, S) -> {noreply, S}.

next/kernel/sandbox.erl

@@ -0,0 +1,41 @@
+-module(sandbox).
+-export([eval_pure/2, eval_pure/3]).
+
+%% Sandboxed evaluation of an Erlang fun.
+%%
+%% eval_pure/2(Fun, Arg)            -> {ok, Result} | {error, Reason}
+%% eval_pure/3(Fun, Arg1, Arg2)     -> {ok, Result} | {error, Reason}
+%%
+%% The 3-arity variant matches the (Activity, State) -> NewState
+%% shape of projection folds. The projection scheduler can wrap
+%% every fold call in `sandbox:eval_pure(Fun, Act, State)` to
+%% ensure a misbehaving fold body can't crash the projection
+%% gen_server.
+%%
+%% v1 sandboxing is just the try/catch envelope: no gas budget,
+%% no IO denial, no environment stripping. Real sandboxing lands
+%% with SX-source eval (the fold body would then be an SX form
+%% evaluated under the spec/harness platform). The API shape is
+%% stable — callers don't need to change when that arrives.
+
+%% Port note: this Erlang implementation catches by explicit
+%% class names (throw, error, exit) rather than the open
+%% `Class:Reason` pattern. The wrappers below enumerate the three.
+
+eval_pure(Fun, Arg) ->
+    try Fun(Arg) of
+        Result -> {ok, Result}
+    catch
+        throw:Reason -> {error, {throw, Reason}};
+        error:Reason -> {error, {error, Reason}};
+        exit:Reason  -> {error, {exit, Reason}}
+    end.
+
+eval_pure(Fun, Arg1, Arg2) ->
+    try Fun(Arg1, Arg2) of
+        Result -> {ok, Result}
+    catch
+        throw:Reason -> {error, {throw, Reason}};
+        error:Reason -> {error, {error, Reason}};
+        exit:Reason  -> {error, {exit, Reason}}
+    end.

next/kernel/term_codec.erl

@@ -0,0 +1,105 @@
+-module(term_codec).
+-export([encode/1, decode/1]).
+
+%% Erlang-side term <-> binary codec, built on the substrate fixes from
+%% commits 24e3bf53 (binary_to_list / list_to_binary), 3d80bd8c ($X char
+%% literals), 4852cca9 (atom_to_list / integer_to_list charlists).
+%%
+%% Wire format (netstring-ish; all length headers ASCII decimal):
+%%
+%%   atom        $a Len $: NameBytes
+%%   integer     $i Len $: DecimalBytes   (negative ints carry leading $-)
+%%   binary      $b Len $: RawBytes
+%%   tuple       $t Count $: Enc1 Enc2 ... Encn
+%%   list        $l Count $: Enc1 Enc2 ... Encn      (proper list)
+%%   nil         $l $0 $:                            (empty list)
+%%
+%% Each Enc is itself one of these forms — recursive. The format is
+%% byte-clean: binary bodies may contain any byte (newlines, NULs, etc.),
+%% so callers can frame entries with a 4-byte big-endian length prefix
+%% (Step 3b on-disk segment writer's job).
+
+%% encode/1: term -> binary
+encode(T) when is_atom(T) ->
+    Cs = atom_to_list(T),
+    list_to_binary([$a, integer_to_list(length(Cs)), $:, Cs]);
+encode(T) when is_integer(T) ->
+    Cs = integer_to_list(T),
+    list_to_binary([$i, integer_to_list(length(Cs)), $:, Cs]);
+encode(T) when is_binary(T) ->
+    list_to_binary([$b, integer_to_list(byte_size(T)), $:, T]);
+encode(T) when is_tuple(T) ->
+    L = tuple_to_list(T),
+    list_to_binary([$t, integer_to_list(length(L)), $:,
+                    [encode(E) || E <- L]]);
+encode([]) ->
+    list_to_binary([$l, $0, $:]);
+encode(T) when is_list(T) ->
+    list_to_binary([$l, integer_to_list(length(T)), $:,
+                    [encode(E) || E <- T]]).
+
+%% decode/1: binary -> {ok, Term, RestBinary} | {error, badform}
+%% On success returns the remaining unconsumed bytes so callers can
+%% stream-decode multiple frames from one buffer.
+decode(B) when is_binary(B) ->
+    decode_chars(binary_to_list(B)).
+
+decode_chars([$a | Rest]) ->
+    {Len, Rest1} = read_len(Rest, 0),
+    Rest2 = strip_colon(Rest1),
+    {NameChars, Rest3} = split_at(Len, Rest2),
+    {ok, list_to_atom(NameChars), list_to_binary(Rest3)};
+decode_chars([$i | Rest]) ->
+    {Len, Rest1} = read_len(Rest, 0),
+    Rest2 = strip_colon(Rest1),
+    {NumChars, Rest3} = split_at(Len, Rest2),
+    {ok, list_to_integer(NumChars), list_to_binary(Rest3)};
+decode_chars([$b | Rest]) ->
+    {Len, Rest1} = read_len(Rest, 0),
+    Rest2 = strip_colon(Rest1),
+    {Bytes, Rest3} = split_at(Len, Rest2),
+    {ok, list_to_binary(Bytes), list_to_binary(Rest3)};
+decode_chars([$t | Rest]) ->
+    {N, Rest1} = read_len(Rest, 0),
+    Rest2 = strip_colon(Rest1),
+    {Elems, Rest3} = decode_n(N, Rest2, []),
+    {ok, list_to_tuple(Elems), list_to_binary(Rest3)};
+decode_chars([$l | Rest]) ->
+    {N, Rest1} = read_len(Rest, 0),
+    Rest2 = strip_colon(Rest1),
+    {Elems, Rest3} = decode_n(N, Rest2, []),
+    {ok, Elems, list_to_binary(Rest3)};
+decode_chars(_) ->
+    {error, badform}.
+
+read_len([C | Rest], Acc) when C >= $0, C =< $9 ->
+    read_len(Rest, Acc * 10 + C - $0);
+read_len([$- | Rest], 0) ->
+    %% Leading minus for negative integer-body lengths is invalid for
+    %% lengths, but appears inside integer-body bytes (handled in
+    %% the body, not here — read_len only consumes digits before $:).
+    {0, [$- | Rest]};
+read_len(Rest, Acc) ->
+    {Acc, Rest}.
+
+strip_colon([$: | Rest]) -> Rest;
+strip_colon(Other) -> erlang:error({badform, Other}).
+
+split_at(0, Rest) -> {[], Rest};
+split_at(N, [H | T]) ->
+    {Hs, Tl} = split_at(N - 1, T),
+    {[H | Hs], Tl};
+split_at(_, []) ->
+    erlang:error({badform, short}).
+
+decode_n(0, Rest, Acc) ->
+    {lists:reverse(Acc), Rest};
+decode_n(N, Bytes, Acc) ->
+    {Term, Rest} = decode_one(Bytes),
+    decode_n(N - 1, Rest, [Term | Acc]).
+
+decode_one(Bytes) ->
+    case decode_chars(Bytes) of
+        {ok, Term, RestBin} -> {Term, binary_to_list(RestBin)};
+        {error, R} -> erlang:error({badform, R})
+    end.

next/tests/actor_lifecycle.sh

@@ -0,0 +1,164 @@
+#!/usr/bin/env bash
+# next/tests/actor_lifecycle.sh — m2 Step 2c end-to-end test.
+#
+# Ties Step 2a artefacts (genesis Person/Service/Group SX files),
+# Step 2b projection (actor_state.erl), and Step 2c bootstrap
+# (nx_kernel:bootstrap_actor/4) together. Profiles bootstrap as
+# Create{Person|Service|Group} activities; the actor_state projection
+# folds them into the per-actor profile registry.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Two actors share signing-key bytes (each in its own AS). The
+# profile's :public_keys list is what gets wrapped in the Create
+# object; the kernel-side AS proplist (built by bootstrap_actor/4
+# from :public_keys) is what envelope:verify_signature reads.
+ALICE_KM='AliceK = <<1,2,3,4>>, AliceKey = [{id, k1}, {created, 0}, {value, AliceK}], AlicePks = [AliceKey], AliceKS = [{key_id, k1}, {algorithm, ed25519}, {value, AliceK}],'
+BOB_KM='BobK = <<5,6,7,8>>, BobKey = [{id, k1}, {created, 0}, {value, BobK}], BobPks = [BobKey], BobKS = [{key_id, k1}, {algorithm, ed25519}, {value, BobK}],'
+ALICE_PROFILE='AliceProfile = [{type, person}, {name, alice_n}, {preferredUsername, alice_local}, {public_keys, AlicePks}],'
+BOB_PROFILE='BobProfile = [{type, service}, {name, bobbot_n}, {preferredUsername, bobbot_local}, {public_keys, BobPks}],'
+
+# actor_state projection wiring — fold_fn from actor_state:fold_fn/0,
+# initial state = actor_state:new().
+PROJ_SETUP='projection:start_link(actors, actor_state:new(), actor_state:fold_fn()),'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/projection.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/actor_state.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_kernel.erl\")) :name)")
+
+;; Pure: bootstrap_actor/4 on a fresh kernel publishes Create and
+;; returns {ok, Result, S}.
+(epoch 10)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} case nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()) of {ok, _, _} -> ok; _ -> bad end\") :name)")
+
+;; Pure: after bootstrap, log_tip = 1, has_actor true
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} {ok, _, S} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()), nx_kernel:has_actor(alice, S) andalso nx_kernel:actor_log_tip(alice, S) =:= 1\") :name)")
+
+;; Pure: log entry is a Create with object's type = person
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} {ok, _, S} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()), {ok, L} = nx_kernel:actor_log_state(alice, S), [E] = log:entries(L), {ok, create} = envelope:get_field(type, E), {ok, Obj} = envelope:get_field(object, E), envelope:get_field(type, Obj) =:= {ok, person}\") :name)")
+
+;; Pure: bootstrap into existing kernel with another actor
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} {ok, _, S1} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()), {ok, _, S2} = nx_kernel:bootstrap_actor(bobbot, BobProfile, BobKS, S1), nx_kernel:actors(S2) =:= [alice, bobbot]\") :name)")
+
+;; Pure: two actors have independent log_tips
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} {ok, _, S1} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()), {ok, _, S2} = nx_kernel:bootstrap_actor(bobbot, BobProfile, BobKS, S1), {nx_kernel:actor_log_tip(alice, S2), nx_kernel:actor_log_tip(bobbot, S2)} =:= {1, 1}\") :name)")
+
+;; Pure: duplicate bootstrap_actor returns already_present
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} {ok, _, S1} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, nx_kernel:new()), case nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS, S1) of {error, already_present, _} -> ok; _ -> bad end\") :name)")
+
+;; gen_server: bootstrap_actor/3 publishes + actor_state projection captures profile
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} nx_kernel:start_link(seed, AliceKS, [{public_keys, AlicePks}]), ${PROJ_SETUP} nx_kernel:with_projections_for(seed, [actors]), {ok, _} = nx_kernel:bootstrap_actor(alice, AliceProfile, AliceKS), nx_kernel:has_actor(seed, nx_kernel:query()) andalso nx_kernel:has_actor(alice, nx_kernel:query())\") :name)")
+
+;; gen_server: actor_state projection captures the bootstrapped Person profile
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} nx_kernel:start_link(seed, AliceKS, [{public_keys, AlicePks}]), ${PROJ_SETUP} nx_kernel:with_projections_for(alice_pre, [actors]), nx_kernel:add_actor(alice_pre, AliceKS, [{public_keys, AlicePks}]), nx_kernel:with_projections_for(alice_pre, [actors]), {ok, _} = nx_kernel:publish_to(alice_pre, [{type, create}, {object, [{type, person}, {name, alice_n}, {preferredUsername, alice_local}, {public_keys, AlicePks}]}]), {ok, Profile} = actor_state:lookup(alice_pre, projection:query(actors)), actor_state:profile_type(Profile) =:= person andalso actor_state:profile_name(Profile) =:= alice_n\") :name)")
+
+;; gen_server: Service profile lands as service in actor_state
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} nx_kernel:start_link(seed, BobKS, [{public_keys, BobPks}]), ${PROJ_SETUP} nx_kernel:add_actor(bobbot, BobKS, [{public_keys, BobPks}]), nx_kernel:with_projections_for(bobbot, [actors]), {ok, _} = nx_kernel:publish_to(bobbot, [{type, create}, {object, [{type, service}, {name, bobbot_n}, {public_keys, BobPks}]}]), {ok, Profile} = actor_state:lookup(bobbot, projection:query(actors)), actor_state:profile_type(Profile) =:= service\") :name)")
+
+;; gen_server: Group profile lands as group in actor_state
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} nx_kernel:start_link(seed, AliceKS, [{public_keys, AlicePks}]), ${PROJ_SETUP} nx_kernel:add_actor(wg1, AliceKS, [{public_keys, AlicePks}]), nx_kernel:with_projections_for(wg1, [actors]), {ok, _} = nx_kernel:publish_to(wg1, [{type, create}, {object, [{type, group}, {name, working_group_n}, {public_keys, AlicePks}]}]), {ok, Profile} = actor_state:lookup(wg1, projection:query(actors)), actor_state:profile_type(Profile) =:= group\") :name)")
+
+;; Sanity: profile captures :preferredUsername + :public_keys from the Create object
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} ${BOB_KM} ${ALICE_PROFILE} ${BOB_PROFILE} nx_kernel:start_link(seed, AliceKS, [{public_keys, AlicePks}]), ${PROJ_SETUP} nx_kernel:add_actor(alice, AliceKS, [{public_keys, AlicePks}]), nx_kernel:with_projections_for(alice, [actors]), {ok, _} = nx_kernel:publish_to(alice, [{type, create}, {object, [{type, person}, {name, alice_n}, {preferredUsername, alice_local}, {public_keys, AlicePks}]}]), {ok, Profile} = actor_state:lookup(alice, projection:query(actors)), actor_state:profile_field(preferredUsername, Profile) =:= {ok, alice_local} andalso actor_state:profile_field(public_keys, Profile) =:= {ok, AlicePks}\") :name)")
+
+;; Pure: profile defaults to person when :type missing
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} TypelessProfile = [{name, alice_n}, {public_keys, AlicePks}], {ok, _, S} = nx_kernel:bootstrap_actor(alice, TypelessProfile, AliceKS, nx_kernel:new()), {ok, L} = nx_kernel:actor_log_state(alice, S), [E] = log:entries(L), {ok, Obj} = envelope:get_field(object, E), envelope:get_field(type, Obj) =:= {ok, person}\") :name)")
+
+;; Pure: empty profile :public_keys defaults to []
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${ALICE_KM} EmptyProfile = [{type, person}, {name, alice_n}], case nx_kernel:bootstrap_actor(alice, EmptyProfile, AliceKS, nx_kernel:new()) of {ok, _, _} -> ok; {error, _, _} -> ok end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "gen_server loaded"                "gen_server"
+check  9  "nx_kernel loaded"                  "nx_kernel"
+check 10  "bootstrap_actor/4 -> {ok, _, _}"   "ok"
+check 11  "bootstrap_actor advances log_tip"  "true"
+check 12  "log entry is Create{Person}"       "true"
+check 13  "two actors live in one kernel"     "true"
+check 14  "independent log_tips after boot"   "true"
+check 15  "duplicate boot -> already_present" "ok"
+check 16  "gen_server bootstrap_actor/3"      "true"
+check 17  "actor_state captures Person"       "true"
+check 18  "actor_state captures Service"      "true"
+check 19  "actor_state captures Group"        "true"
+check 20  "profile carries preferredUsername" "true"
+check 21  "typeless profile defaults Person"  "true"
+check 22  "empty public_keys handled"         "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/actor_lifecycle.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/actor_state_pure.sh

@@ -0,0 +1,163 @@
+#!/usr/bin/env bash
+# next/tests/actor_state_pure.sh — m2 Step 2b test.
+#
+# Exercises the Erlang-fun stand-in for the actor-state projection
+# fold. Activities flow:
+#   Create{Person|Service|Group} -> profile registered
+#   Update{Person|Service|Group, patch} -> patch deep-merged
+#   Move -> :moved_to recorded
+# Non-actor object Creates pass through.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/actor_state.erl\")) :name)")
+
+;; new/0 returns []
+(epoch 10)
+(eval "(get (erlang-eval-ast \"actor_state:new() =:= []\") :name)")
+
+;; has/2 false on empty
+(epoch 11)
+(eval "(get (erlang-eval-ast \"actor_state:has(alice, actor_state:new()) =:= false\") :name)")
+
+;; lookup/2 not_found on empty
+(epoch 12)
+(eval "(get (erlang-eval-ast \"actor_state:lookup(alice, actor_state:new()) =:= not_found\") :name)")
+
+;; actors/1 returns [] on empty
+(epoch 13)
+(eval "(get (erlang-eval-ast \"actor_state:actors(actor_state:new()) =:= []\") :name)")
+
+;; Create{Person} registers profile
+(epoch 14)
+(eval "(get (erlang-eval-ast \"Obj = [{type, person}, {name, alice_name}, {preferredUsername, alice_local}], Act = [{actor, alice}, {type, create}, {object, Obj}, {published, 1}], S = actor_state:fold(Act, actor_state:new()), actor_state:has(alice, S)\") :name)")
+
+;; Profile carries :type, :name, :preferredUsername, :created
+(epoch 15)
+(eval "(get (erlang-eval-ast \"Obj = [{type, person}, {name, alice_name}, {preferredUsername, alice_local}], Act = [{actor, alice}, {type, create}, {object, Obj}, {published, 7}], S = actor_state:fold(Act, actor_state:new()), {ok, P} = actor_state:lookup(alice, S), {actor_state:profile_type(P), actor_state:profile_name(P), actor_state:profile_field(preferredUsername, P), actor_state:profile_field(created, P)} =:= {person, alice_name, {ok, alice_local}, {ok, 7}}\") :name)")
+
+;; Create{Service} also registers
+(epoch 16)
+(eval "(get (erlang-eval-ast \"Obj = [{type, service}, {name, feedbot}], Act = [{actor, feed1}, {type, create}, {object, Obj}, {published, 1}], S = actor_state:fold(Act, actor_state:new()), {ok, P} = actor_state:lookup(feed1, S), actor_state:profile_type(P) =:= service\") :name)")
+
+;; Create{Group} also registers
+(epoch 17)
+(eval "(get (erlang-eval-ast \"Obj = [{type, group}, {name, working_group}], Act = [{actor, wg1}, {type, create}, {object, Obj}, {published, 1}], S = actor_state:fold(Act, actor_state:new()), {ok, P} = actor_state:lookup(wg1, S), actor_state:profile_type(P) =:= group\") :name)")
+
+;; Create{Note} is pass-through (non-actor object)
+(epoch 18)
+(eval "(get (erlang-eval-ast \"Obj = [{type, note}, {content, hi}], Act = [{actor, alice}, {type, create}, {object, Obj}, {published, 1}], actor_state:fold(Act, actor_state:new()) =:= []\") :name)")
+
+;; Duplicate Create doesn't overwrite an existing profile
+(epoch 19)
+(eval "(get (erlang-eval-ast \"O1 = [{type, person}, {name, alice_v1}], O2 = [{type, person}, {name, alice_v2}], A1 = [{actor, alice}, {type, create}, {object, O1}, {published, 1}], A2 = [{actor, alice}, {type, create}, {object, O2}, {published, 2}], S1 = actor_state:fold(A1, actor_state:new()), S2 = actor_state:fold(A2, S1), {ok, P} = actor_state:lookup(alice, S2), actor_state:profile_name(P) =:= alice_v1\") :name)")
+
+;; Two distinct actors live side by side
+(epoch 20)
+(eval "(get (erlang-eval-ast \"PO = [{type, person}, {name, alice_n}], SO = [{type, service}, {name, bobbot_n}], A1 = [{actor, alice}, {type, create}, {object, PO}, {published, 1}], A2 = [{actor, bobbot}, {type, create}, {object, SO}, {published, 2}], S = actor_state:fold(A2, actor_state:fold(A1, actor_state:new())), actor_state:actors(S) =:= [alice, bobbot]\") :name)")
+
+;; Update merges patch
+(epoch 21)
+(eval "(get (erlang-eval-ast \"PO = [{type, person}, {name, alice_n}], A1 = [{actor, alice}, {type, create}, {object, PO}, {published, 1}], A2 = [{actor, alice}, {type, update}, {patch, [{summary, new_bio}]}, {published, 2}], S = actor_state:fold(A2, actor_state:fold(A1, actor_state:new())), {ok, P} = actor_state:lookup(alice, S), actor_state:profile_field(summary, P) =:= {ok, new_bio}\") :name)")
+
+;; Update overwrites individual fields (last-write-wins per key)
+(epoch 22)
+(eval "(get (erlang-eval-ast \"PO = [{type, person}, {name, alice_v1}], A1 = [{actor, alice}, {type, create}, {object, PO}, {published, 1}], A2 = [{actor, alice}, {type, update}, {patch, [{name, alice_v2}]}, {published, 2}], S = actor_state:fold(A2, actor_state:fold(A1, actor_state:new())), {ok, P} = actor_state:lookup(alice, S), actor_state:profile_name(P) =:= alice_v2\") :name)")
+
+;; Update for unknown actor is pass-through
+(epoch 23)
+(eval "(get (erlang-eval-ast \"A = [{actor, ghost}, {type, update}, {patch, [{summary, x}]}, {published, 1}], actor_state:fold(A, actor_state:new()) =:= []\") :name)")
+
+;; Move records :moved_to
+(epoch 24)
+(eval "(get (erlang-eval-ast \"PO = [{type, person}, {name, alice_n}], A1 = [{actor, alice}, {type, create}, {object, PO}, {published, 1}], A2 = [{actor, alice}, {type, move}, {moved_to, new_alice}, {published, 2}], S = actor_state:fold(A2, actor_state:fold(A1, actor_state:new())), {ok, P} = actor_state:lookup(alice, S), actor_state:profile_field(moved_to, P) =:= {ok, new_alice}\") :name)")
+
+;; fold_fn/0 is a 2-arity Erlang fun usable by projection:start_link
+(epoch 25)
+(eval "(get (erlang-eval-ast \"F = actor_state:fold_fn(), is_function(F, 2)\") :name)")
+
+;; fold ignores activities with no :actor field
+(epoch 26)
+(eval "(get (erlang-eval-ast \"Obj = [{type, person}, {name, x}], Act = [{type, create}, {object, Obj}, {published, 1}], actor_state:fold(Act, actor_state:new()) =:= []\") :name)")
+
+;; public_keys field is captured at Create time
+(epoch 27)
+(eval "(get (erlang-eval-ast \"Keys = [[{id, k1}, {value, <<1,2,3,4>>}]], Obj = [{type, person}, {name, alice_n}, {public_keys, Keys}], Act = [{actor, alice}, {type, create}, {object, Obj}, {published, 1}], S = actor_state:fold(Act, actor_state:new()), {ok, P} = actor_state:lookup(alice, S), actor_state:profile_field(public_keys, P) =:= {ok, Keys}\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  3  "actor_state module loaded"          "actor_state"
+check 10  "new/0 -> []"                        "true"
+check 11  "has/2 false on empty"               "true"
+check 12  "lookup/2 not_found on empty"        "true"
+check 13  "actors/1 [] on empty"               "true"
+check 14  "Create{Person} registers actor"    "true"
+check 15  "Profile carries type/name/created"  "true"
+check 16  "Create{Service} registers actor"    "true"
+check 17  "Create{Group} registers actor"      "true"
+check 18  "Create{Note} pass-through"          "true"
+check 19  "Duplicate Create no-overwrite"      "true"
+check 20  "Two actors side by side"            "true"
+check 21  "Update merges new fields"           "true"
+check 22  "Update last-write-wins per key"     "true"
+check 23  "Update unknown actor pass-through"  "true"
+check 24  "Move records :moved_to"             "true"
+check 25  "fold_fn/0 is fun/2"                 "true"
+check 26  "Activity sans :actor pass-through"  "true"
+check 27  "public_keys captured at Create"     "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/actor_state_pure.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/auto_accept.sh

@@ -0,0 +1,138 @@
+#!/usr/bin/env bash
+# next/tests/auto_accept.sh — m2 Step 6c test.
+#
+# Per design §13.2 the v2 Follow policy is open-world: every
+# successfully-ingested Follow triggers an Accept publish from the
+# target actor. Enabled per-Cfg via {auto_accept_follows, true};
+# off by default so manual-moderation deployments can opt out.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Alice is on this kernel (target). Bob is the peer (signs Follow
+# with BobKS). Alice's outbox projection is `followers` so when
+# alice publishes the Accept, it folds through follower_graph too —
+# both sides of the relationship update without any test scaffolding.
+SETUP='AK = <<1,2,3,4>>, AKS = [{key_id,k1},{algorithm,ed25519},{value,AK}], AAS = [{public_keys,[[{id,k1},{created,0},{value,AK}]]}], BK = <<5,6,7,8>>, BKS = [{key_id,k1},{algorithm,ed25519},{value,BK}], BAS = [{public_keys,[[{id,k1},{created,0},{value,BK}]]}], FollowEnv = outbox:construct(follow, bob, 1, alice), SignedFollow = outbox:sign(FollowEnv, BKS), Body = term_codec:encode(SignedFollow), projection:start_link(followers, follower_graph:new(), follower_graph:fold_fn()), nx_kernel:start_link(alice, AKS, AAS), nx_kernel:with_projections_for(alice, [followers]), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}, {auto_accept_follows, true}], InboxPath = <<47,97,99,116,111,114,115,47,97,108,105,99,101,47,105,110,98,111,120>>,'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/projection.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_kernel.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/term_codec.erl\")) :name)")
+(epoch 10)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+(epoch 11)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+(epoch 12)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery.erl\")) :name)")
+
+;; auto_accept on: Follow ingestion advances alice's outbox tip (Accept published)
+(epoch 20)
+(eval "(erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), nx_kernel:log_tip_for(alice)\")")
+
+;; auto_accept on: alice's outbox entry is an Accept activity
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), {ok, L} = nx_kernel:log_state_for(alice), [E] = log:entries(L), envelope:get_field(type, E) =:= {ok, accept}\") :name)")
+
+;; auto_accept on: follower_graph state converges to full Follow relationship
+;; (alice.followers = [bob], bob.following = [alice]) after both inbox + outbox
+;; projections fold through followers.
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), S = projection:query(followers), {follower_graph:followers(alice, S), follower_graph:following(bob, S)} =:= {[bob], [alice]}\") :name)")
+
+;; auto_accept on: pendings cleared after the Accept fold
+(epoch 23)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), S = projection:query(followers), {follower_graph:pending_inbound(alice, S), follower_graph:pending_outbound(bob, S)} =:= {[], []}\") :name)")
+
+;; auto_accept off (default): no outbox publish; outbox tip stays 0
+(epoch 24)
+(eval "(erlang-eval-ast \"${SETUP} CfgOff = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, CfgOff), nx_kernel:log_tip_for(alice)\")")
+
+;; auto_accept off: pending_inbound still gets populated (Step 6b path)
+;; but no Accept fired, so alice.followers stays empty.
+(epoch 25)
+(eval "(get (erlang-eval-ast \"${SETUP} CfgOff = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, CfgOff), S = projection:query(followers), {follower_graph:pending_inbound(alice, S), follower_graph:followers(alice, S)} =:= {[bob], []}\") :name)")
+
+;; Non-Follow activity (Create{Note}) with auto_accept on: outbox stays empty
+(epoch 26)
+(eval "(erlang-eval-ast \"${SETUP} NoteEnv = outbox:construct(create, bob, 2, [{type, note}, {content, hi}]), SignedNote = outbox:sign(NoteEnv, BKS), NoteBody = term_codec:encode(SignedNote), Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, NoteBody}], http_server:route(Req, Cfg), nx_kernel:log_tip_for(alice)\")")
+
+;; Bad-sig Follow ingestion with auto_accept on: no Accept publish (short-circuit)
+(epoch 27)
+(eval "(erlang-eval-ast \"${SETUP} EvilK = <<9,9,9,9>>, EvilAS = [{public_keys,[[{id,k1},{created,0},{value,EvilK}]]}], EvilCfg = [{peer_as, [{bob, EvilAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}, {auto_accept_follows, true}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, EvilCfg), nx_kernel:log_tip_for(alice)\")")
+EPOCHS
+
+OUTPUT=$(timeout 900 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check 11  "http_server loaded"               "http_server"
+check 20  "auto_accept on: outbox tip = 1"   "1"
+check 21  "outbox entry is an Accept"        "true"
+check 22  "graph converges to full Follow"   "true"
+check 23  "pendings cleared after Accept"    "true"
+check 24  "auto_accept off: outbox tip = 0"  "0"
+check 25  "auto_accept off: pending only"    "true"
+check 26  "non-Follow ingestion: no Accept"  "0"
+check 27  "bad-sig short-circuits Accept"    "0"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/auto_accept.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/backfill.sh

@@ -0,0 +1,170 @@
+#!/usr/bin/env bash
+# next/tests/backfill.sh — m2 Step 9a test.
+#
+# Backfill mode slicing per design §13.3. Given an outbox log +
+# a mode (none / last_n / last_t / full / since_cid), backfill:slice
+# returns the activity list to send to a new follower as backfill.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Five activities published at :published = 1, 2, 3, 4, 5
+SETUP='Act1 = [{id, <<1>>}, {type, note}, {actor, alice}, {published, 1}], Act2 = [{id, <<2>>}, {type, note}, {actor, alice}, {published, 2}], Act3 = [{id, <<3>>}, {type, note}, {actor, alice}, {published, 3}], Act4 = [{id, <<4>>}, {type, note}, {actor, alice}, {published, 4}], Act5 = [{id, <<5>>}, {type, note}, {actor, alice}, {published, 5}], {ok, L0} = log:open(alice, <<98,97,115,101>>), {ok, L1, _} = log:append(L0, Act1), {ok, L2, _} = log:append(L1, Act2), {ok, L3, _} = log:append(L2, Act3), {ok, L4, _} = log:append(L3, Act4), {ok, L5, _} = log:append(L4, Act5),'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/backfill.erl\")) :name)")
+
+;; none mode -> []
+(epoch 10)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice(none, L5) =:= []\") :name)")
+
+;; full mode -> all 5
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice(full, L5) =:= [Act1, Act2, Act3, Act4, Act5]\") :name)")
+
+;; last_n with N=2 -> tail 2 (Act4, Act5)
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_n, 2}, L5) =:= [Act4, Act5]\") :name)")
+
+;; last_n with N > total -> all entries
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_n, 100}, L5) =:= [Act1, Act2, Act3, Act4, Act5]\") :name)")
+
+;; last_n with N = 0 -> []
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_n, 0}, L5) =:= []\") :name)")
+
+;; last_t with T=2, Now=5 -> activities with :published > 3 and <= 5 -> [Act4, Act5]
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_t, 2, fun() -> 5 end}, L5) =:= [Act4, Act5]\") :name)")
+
+;; last_t with T=10, Now=5 -> covers everything from :published > -5 -> all 5
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_t, 10, fun() -> 5 end}, L5) =:= [Act1, Act2, Act3, Act4, Act5]\") :name)")
+
+;; last_t with T=0, Now=5 -> only entries at exactly Now (>0, <=5) — really [] because window is (5..5]
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({last_t, 0, fun() -> 5 end}, L5) =:= []\") :name)")
+
+;; since_cid with the 2nd cid -> entries AFTER it (Act3..Act5)
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({since_cid, <<2>>}, L5) =:= [Act3, Act4, Act5]\") :name)")
+
+;; since_cid with last cid -> []
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({since_cid, <<5>>}, L5) =:= []\") :name)")
+
+;; since_cid with unknown cid -> []
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice({since_cid, <<99>>}, L5) =:= []\") :name)")
+
+;; wrap_backfill adds {backfilled, true} to each entry
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} Wrapped = backfill:slice({last_n, 1}, L5, true), [Act5W] = Wrapped, envelope:get_field(backfilled, Act5W) =:= {ok, true}\") :name)")
+
+;; Wrapped entries preserve :id
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} Wrapped = backfill:slice({last_n, 1}, L5, true), [Act5W] = Wrapped, envelope:get_field(id, Act5W) =:= {ok, <<5>>}\") :name)")
+
+;; parse_mode: nil / none / atoms
+(epoch 23)
+(eval "(get (erlang-eval-ast \"{backfill:parse_mode(nil), backfill:parse_mode(none), backfill:parse_mode(full)} =:= {none, none, full}\") :name)")
+
+;; parse_mode: tuple shapes pass through
+(epoch 24)
+(eval "(get (erlang-eval-ast \"backfill:parse_mode({last_n, 3}) =:= {last_n, 3}\") :name)")
+
+;; parse_mode: proplist with mode + limit
+(epoch 25)
+(eval "(get (erlang-eval-ast \"backfill:parse_mode([{mode, last_n}, {limit, 50}]) =:= {last_n, 50}\") :name)")
+
+;; parse_mode: proplist with mode = full
+(epoch 26)
+(eval "(get (erlang-eval-ast \"backfill:parse_mode([{mode, full}]) =:= full\") :name)")
+
+;; parse_mode: unknown -> none
+(epoch 27)
+(eval "(get (erlang-eval-ast \"backfill:parse_mode([{mode, mystery}]) =:= none\") :name)")
+
+;; Unknown mode -> []
+(epoch 28)
+(eval "(get (erlang-eval-ast \"${SETUP} backfill:slice(garbage, L5) =:= []\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 280 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  4  "backfill module loaded"        "backfill"
+check 10  "none mode -> []"               "true"
+check 11  "full mode -> all 5"            "true"
+check 12  "last_n N=2 -> tail 2"          "true"
+check 13  "last_n N=100 -> all 5"         "true"
+check 14  "last_n N=0 -> []"              "true"
+check 15  "last_t T=2 Now=5 -> 4,5"       "true"
+check 16  "last_t T=10 Now=5 -> all 5"    "true"
+check 17  "last_t T=0 Now=5 -> []"        "true"
+check 18  "since_cid mid -> tail 3"       "true"
+check 19  "since_cid last -> []"          "true"
+check 20  "since_cid unknown -> []"       "true"
+check 21  "wrap adds backfilled=true"     "true"
+check 22  "wrap preserves :id"            "true"
+check 23  "parse_mode atoms"              "true"
+check 24  "parse_mode tuple passthrough"  "true"
+check 25  "parse_mode proplist last_n"    "true"
+check 26  "parse_mode proplist full"      "true"
+check 27  "parse_mode unknown -> none"    "true"
+check 28  "unknown slice mode -> []"      "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/backfill.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/backfill_drain.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+# next/tests/backfill_drain.sh — m2 Step 9c test.
+#
+# Auto-Accept on Follow ingestion can now also drain the receiving
+# actor's outbox into the new follower's delivery_worker queue per
+# the Follow's :backfill spec. Gated by Cfg :backfill_enabled.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Alice is the target (on this kernel). Bob is the peer publishing the
+# Follow. Three notes pre-published to alice's outbox before bob's
+# Follow lands; the Follow asks for last_n=2 backfill.
+SETUP='AK = <<1,2,3,4>>, AKS = [{key_id,k1},{algorithm,ed25519},{value,AK}], AAS = [{public_keys,[[{id,k1},{created,0},{value,AK}]]}], BK = <<5,6,7,8>>, BKS = [{key_id,k1},{algorithm,ed25519},{value,BK}], BAS = [{public_keys,[[{id,k1},{created,0},{value,BK}]]}], FollowReq = [{type, follow}, {object, alice}], FollowReqBF = [{type, follow}, {object, alice}, {backfill, {last_n, 2}}], FollowEnvBF = outbox:construct(follow, bob, 1, alice), FollowSignedNoBF = outbox:sign(FollowEnvBF, BKS), FollowSignedBF = outbox:sign(FollowEnvBF ++ [{backfill, {last_n, 2}}], BKS), BodyBF = term_codec:encode(FollowSignedBF), BodyNoBF = term_codec:encode(FollowSignedNoBF), nx_kernel:start_link(alice, AKS, AAS), delivery_worker:start_link(bob), InboxPath = <<47,97,99,116,111,114,115,47,97,108,105,99,101,47,105,110,98,111,120>>,'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/backfill.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_worker.erl\")) :name)")
+(epoch 10)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+(epoch 11)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_kernel.erl\")) :name)")
+(epoch 12)
+(eval "(get (erlang-load-module (file-read \"next/kernel/term_codec.erl\")) :name)")
+(epoch 13)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; backfill_enabled + Follow with :backfill last_n=2 + 3 pre-published
+;; notes -> bob's delivery_worker has 2 pending entries after Follow lands
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${SETUP} N1 = [{type, note}, {object, [{content, hi1}]}], N2 = [{type, note}, {object, [{content, hi2}]}], N3 = [{type, note}, {object, [{content, hi3}]}], nx_kernel:publish_to(alice, N1), nx_kernel:publish_to(alice, N2), nx_kernel:publish_to(alice, N3), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {auto_accept_follows, true}, {backfill_enabled, true}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, BodyBF}], http_server:route(Req, Cfg), length(delivery_worker:pending_srv(bob)) =:= 2\") :name)")
+
+;; Each backfilled entry carries {backfilled, true}
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} N1 = [{type, note}, {object, [{content, hi}]}], nx_kernel:publish_to(alice, N1), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {auto_accept_follows, true}, {backfill_enabled, true}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, BodyBF}], http_server:route(Req, Cfg), [E | _] = delivery_worker:pending_srv(bob), envelope:get_field(backfilled, E) =:= {ok, true}\") :name)")
+
+;; No :backfill_enabled flag -> no backfill drain even with :backfill in Follow
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} N1 = [{type, note}, {object, [{content, hi}]}], nx_kernel:publish_to(alice, N1), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {auto_accept_follows, true}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, BodyBF}], http_server:route(Req, Cfg), delivery_worker:pending_srv(bob) =:= []\") :name)")
+
+;; Follow without :backfill field -> no backfill drain (even with the flag)
+(epoch 23)
+(eval "(get (erlang-eval-ast \"${SETUP} N1 = [{type, note}, {object, [{content, hi}]}], nx_kernel:publish_to(alice, N1), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {auto_accept_follows, true}, {backfill_enabled, true}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, BodyNoBF}], http_server:route(Req, Cfg), delivery_worker:pending_srv(bob) =:= []\") :name)")
+
+;; Missing delivery_worker for the peer -> silently skipped (no enqueue, no crash)
+(epoch 24)
+(eval "(get (erlang-eval-ast \"AK = <<1,2,3,4>>, AKS = [{key_id,k1},{algorithm,ed25519},{value,AK}], AAS = [{public_keys,[[{id,k1},{created,0},{value,AK}]]}], BK = <<5,6,7,8>>, BKS = [{key_id,k1},{algorithm,ed25519},{value,BK}], BAS = [{public_keys,[[{id,k1},{created,0},{value,BK}]]}], nx_kernel:start_link(alice, AKS, AAS), FollowEnvBF = outbox:construct(follow, bob, 1, alice), FollowSignedBF = outbox:sign(FollowEnvBF ++ [{backfill, {last_n, 2}}], BKS), BodyBF = term_codec:encode(FollowSignedBF), N1 = [{type, note}, {object, [{content, hi}]}], nx_kernel:publish_to(alice, N1), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {auto_accept_follows, true}, {backfill_enabled, true}], InboxPath = <<47,97,99,116,111,114,115,47,97,108,105,99,101,47,105,110,98,111,120>>, Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, BodyBF}], case http_server:route(Req, Cfg) of [{status, 202}, _, _] -> true; _ -> false end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 900 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check 13  "http_server loaded"               "http_server"
+check 20  "Follow w/ backfill -> 2 enqueued" "true"
+check 21  "backfilled marker on entries"     "true"
+check 22  "no flag -> no backfill"           "true"
+check 23  "no :backfill field -> no drain"   "true"
+check 24  "missing worker -> 202 (skip)"     "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/backfill_drain.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/bootstrap_build.sh

@@ -0,0 +1,127 @@
+#!/usr/bin/env bash
+# next/tests/bootstrap_build.sh — Step 4d acceptance test.
+#
+# Exercises bootstrap:build_genesis/1, verify_genesis/2,
+# cidhash_path/1, write_cidhash/2, read_cidhash/1. The bundle CID
+# is computed by delegating to the host cid:to_string BIF (Step 1b
+# substrate) over the read_genesis result. 11 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+# Clean any stale .cidhash from previous runs before tests touch
+# the filesystem.
+rm -f next/genesis/.cidhash
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE; rm -f next/genesis/.cidhash" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/bootstrap.erl\")) :name)")
+
+;; build_genesis returns {ok, [{cid, _}, {sections, _}]}
+(epoch 10)
+(eval "(erlang-eval-ast \"{ok, B} = bootstrap:build_genesis(bootstrap:read_genesis()), {Tag, _} = hd(B), Tag\")")
+
+;; The CID is a non-empty binary
+(epoch 11)
+(eval "(get (erlang-eval-ast \"{ok, [{cid, C}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), is_binary(C)\") :name)")
+(epoch 12)
+(eval "(get (erlang-eval-ast \"{ok, [{cid, C}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), byte_size(C) > 50\") :name)")
+
+;; build_genesis is deterministic across calls
+(epoch 13)
+(eval "(get (erlang-eval-ast \"{ok, [{cid, C1}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), {ok, [{cid, C2}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), C1 =:= C2\") :name)")
+
+;; build_genesis preserves the sections list
+(epoch 14)
+(eval "(erlang-eval-ast \"{ok, [_, {sections, S}]} = bootstrap:build_genesis(bootstrap:read_genesis()), length(S)\")")
+
+;; build_genesis rejects bad input shapes
+(epoch 15)
+(eval "(get (erlang-eval-ast \"case bootstrap:build_genesis({error, broken}) of {error, {bad_read_result, _}} -> ok; _ -> bad end\") :name)")
+
+;; verify_genesis returns ok when CID matches
+(epoch 20)
+(eval "(get (erlang-eval-ast \"{ok, [{cid, C}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), bootstrap:verify_genesis(bootstrap:read_genesis(), C) =:= ok\") :name)")
+
+;; verify_genesis returns {error, {cid_mismatch, _, _}} when CID doesn't match
+(epoch 21)
+(eval "(get (erlang-eval-ast \"case bootstrap:verify_genesis(bootstrap:read_genesis(), <<99,99,99>>) of {error, {cid_mismatch, _, _}} -> ok; _ -> bad end\") :name)")
+
+;; cidhash_path concatenation
+(epoch 22)
+(eval "(get (erlang-eval-ast \"bootstrap:cidhash_path(<<110,101,120,116>>) =:= <<110,101,120,116,47,46,99,105,100,104,97,115,104>>\") :name)")
+
+;; write_cidhash + read_cidhash round-trip the bundle CID
+(epoch 23)
+(eval "(get (erlang-eval-ast \"{ok, [{cid, C}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), Base = bootstrap:default_base(), ok = bootstrap:write_cidhash(Base, C), {ok, Stored} = bootstrap:read_cidhash(Base), Stored =:= C\") :name)")
+
+;; Full verify path against the persisted .cidhash
+(epoch 24)
+(eval "(get (erlang-eval-ast \"Base = bootstrap:default_base(), {ok, [{cid, C}, _]} = bootstrap:build_genesis(bootstrap:read_genesis()), ok = bootstrap:write_cidhash(Base, C), {ok, Stored} = bootstrap:read_cidhash(Base), bootstrap:verify_genesis(bootstrap:read_genesis(), Stored) =:= ok\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 180 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                "bootstrap"
+check 10  "build_genesis head tag"          "cid"
+check 11  "CID is a binary"                 "true"
+check 12  "CID length > 50"                 "true"
+check 13  "build_genesis deterministic"     "true"
+check 14  "sections preserved (7 entries)"  "7"
+check 15  "build_genesis rejects bad shape" "ok"
+check 20  "verify_genesis ok when match"    "true"
+check 21  "verify_genesis errs on mismatch" "ok"
+check 22  "cidhash_path concatenation"      "true"
+check 23  "write/read_cidhash round-trip"   "true"
+check 24  "verify against persisted hash"   "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/bootstrap_build.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/bootstrap_load.sh

@@ -0,0 +1,126 @@
+#!/usr/bin/env bash
+# next/tests/bootstrap_load.sh — Step 4e acceptance test.
+#
+# Exercises bootstrap:load_genesis/1 + strip_sx_suffix/1.
+# Walks bootstrap:read_genesis output, strips .sx from each
+# filename, registers raw bytes as entries under the matching
+# kind. 13 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/registry.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/bootstrap.erl\")) :name)")
+
+;; strip_sx_suffix on "create.sx" -> "create"
+(epoch 10)
+(eval "(get (erlang-eval-ast \"bootstrap:strip_sx_suffix(<<99,114,101,97,116,101,46,115,120>>) =:= <<99,114,101,97,116,101>>\") :name)")
+
+;; strip_sx_suffix unchanged on names without .sx
+(epoch 11)
+(eval "(get (erlang-eval-ast \"bootstrap:strip_sx_suffix(<<104,101,108,108,111>>) =:= <<104,101,108,108,111>>\") :name)")
+
+;; strip_sx_suffix on exactly ".sx" -> empty binary
+(epoch 12)
+(eval "(get (erlang-eval-ast \"bootstrap:strip_sx_suffix(<<46,115,120>>) =:= <<>>\") :name)")
+
+;; load_genesis on bad input rejects with proper tag
+(epoch 13)
+(eval "(get (erlang-eval-ast \"case bootstrap:load_genesis({error, broken}) of {error, {bad_read_result, _}} -> ok; _ -> bad end\") :name)")
+
+;; Per-kind counts after load match the section file counts
+(epoch 20)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(activity_types, S))\")")
+(epoch 21)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(object_types, S))\")")
+(epoch 22)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(projections, S))\")")
+(epoch 23)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(validators, S))\")")
+(epoch 24)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(codecs, S))\")")
+(epoch 25)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(sig_suites, S))\")")
+(epoch 26)
+(eval "(erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), length(registry:list(audience, S))\")")
+
+;; registry:lookup retrieves a known entry's bytes
+(epoch 30)
+(eval "(get (erlang-eval-ast \"{ok, S} = bootstrap:load_genesis(bootstrap:read_genesis()), case registry:lookup(activity_types, <<99,114,101,97,116,101>>, S) of {ok, B} -> is_binary(B) and (byte_size(B) > 100); _ -> false end\") :name)")
+
+;; load_genesis is deterministic — compare via cid:to_string of state
+(epoch 31)
+(eval "(get (erlang-eval-ast \"R = bootstrap:read_genesis(), {ok, S1} = bootstrap:load_genesis(R), {ok, S2} = bootstrap:load_genesis(R), cid:to_string(S1) =:= cid:to_string(S2)\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 300 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "registry module loaded"              "registry"
+check  3  "bootstrap module loaded"             "bootstrap"
+check 10  "strip suffix create.sx -> create"    "true"
+check 11  "strip suffix hello unchanged"        "true"
+check 12  "strip suffix .sx -> empty"           "true"
+check 13  "load_genesis rejects bad shape"      "ok"
+check 20  "loaded activity_types count = 5"     "5"
+check 21  "loaded object_types count = 13"      "13"
+check 22  "loaded projections count = 7"        "7"
+check 23  "loaded validators count = 3"         "3"
+check 24  "loaded codecs count = 3"             "3"
+check 25  "loaded sig_suites count = 2"         "2"
+check 26  "loaded audience count = 3"           "3"
+check 30  "registry:lookup activity_types/create" "true"
+check 31  "load_genesis deterministic"          "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/bootstrap_load.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/bootstrap_populate.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+# next/tests/bootstrap_populate.sh — Step 5c-populate acceptance test.
+#
+# Closes the bootstrap → registry loop end-to-end. Each test
+# inlines registry:start_link() with bootstrap:populate_registry()
+# because spawned processes don't survive separate erlang-eval-ast
+# invocations. 11 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Shared prelude: starts registry, runs populate.
+PRELUDE='registry:start_link(), N = bootstrap:populate_registry(),'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/registry.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/bootstrap.erl\")) :name)")
+
+;; populate returns the total count
+(epoch 10)
+(eval "(erlang-eval-ast \"${PRELUDE} N\")")
+
+;; Per-kind counts match the manifest authored in Step 4
+(epoch 20)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(activity_types))\")")
+(epoch 21)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(object_types))\")")
+(epoch 22)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(projections))\")")
+(epoch 23)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(validators))\")")
+(epoch 24)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(codecs))\")")
+(epoch 25)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(sig_suites))\")")
+(epoch 26)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(audience))\")")
+
+;; Lookup of a known entry returns its bytes
+(epoch 30)
+(eval "(get (erlang-eval-ast \"${PRELUDE} case registry:lookup(activity_types, <<99,114,101,97,116,101>>) of {ok, B} -> is_binary(B) and (byte_size(B) > 100); _ -> false end\") :name)")
+
+;; A known object-type entry registered correctly
+(epoch 31)
+(eval "(get (erlang-eval-ast \"${PRELUDE} case registry:lookup(object_types, <<100,101,102,105,110,101,45,97,99,116,105,118,105,116,121>>) of {ok, B} -> is_binary(B); _ -> false end\") :name)")
+
+;; A known validator entry
+(epoch 32)
+(eval "(get (erlang-eval-ast \"${PRELUDE} case registry:lookup(validators, <<101,110,118,101,108,111,112,101,45,115,104,97,112,101>>) of {ok, B} -> is_binary(B); _ -> false end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 600 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "gen_server loaded"                "gen_server"
+check  3  "registry loaded"                  "registry"
+check  4  "bootstrap loaded"                 "bootstrap"
+check 10  "populate returns total 36"        "36"
+check 20  "activity_types count = 5"         "5"
+check 21  "object_types count = 13"          "13"
+check 22  "projections count = 7"            "7"
+check 23  "validators count = 3"             "3"
+check 24  "codecs count = 3"                 "3"
+check 25  "sig_suites count = 2"             "2"
+check 26  "audience count = 3"               "3"
+check 30  "lookup activity_types/create"     "true"
+check 31  "lookup object_types/define-activity" "true"
+check 32  "lookup validators/envelope-shape" "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/bootstrap_populate.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/bootstrap_read.sh

@@ -0,0 +1,123 @@
+#!/usr/bin/env bash
+# next/tests/bootstrap_read.sh — Step 4c acceptance test.
+#
+# Exercises bootstrap:read_genesis/0, read_section/2, sections/0,
+# section_subdir/1, ends_with_sx/1. Verifies per-section file
+# counts match the manifest authored in Steps 4a/4b. 14 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/bootstrap.erl\")) :name)")
+
+;; sections/0 returns 7 atoms
+(epoch 10)
+(eval "(erlang-eval-ast \"length(bootstrap:sections())\")")
+
+;; ends_with_sx — positive on "create.sx", negative on "hello"
+(epoch 11)
+(eval "(get (erlang-eval-ast \"bootstrap:ends_with_sx(<<99,114,101,97,116,101,46,115,120>>)\") :name)")
+(epoch 12)
+(eval "(get (erlang-eval-ast \"bootstrap:ends_with_sx(<<104,101,108,108,111>>)\") :name)")
+(epoch 13)
+(eval "(get (erlang-eval-ast \"bootstrap:ends_with_sx(<<>>)\") :name)")
+
+;; Per-section file counts match the manifest (3/10/7/3/3/2/3)
+(epoch 20)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), activity_types))\")")
+(epoch 21)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), object_types))\")")
+(epoch 22)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), projections))\")")
+(epoch 23)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), validators))\")")
+(epoch 24)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), codecs))\")")
+(epoch 25)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), sig_suites))\")")
+(epoch 26)
+(eval "(erlang-eval-ast \"length(bootstrap:read_section(bootstrap:default_base(), audience))\")")
+
+;; read_genesis/0 returns {ok, [{Section, Entries}, ...]} with 7 entries
+(epoch 30)
+(eval "(erlang-eval-ast \"{ok, G} = bootstrap:read_genesis(), length(G)\")")
+
+;; First entry is {activity_types, [_,_,_]}
+(epoch 31)
+(eval "(get (erlang-eval-ast \"{ok, G} = bootstrap:read_genesis(), {S, Entries} = hd(G), S\") :name)")
+
+;; Each entry has the right number of files
+(epoch 32)
+(eval "(erlang-eval-ast \"{ok, G} = bootstrap:read_genesis(), {_, E} = hd(G), length(E)\")")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                "bootstrap"
+check 10  "sections/0 length"               "7"
+check 11  "ends_with_sx create.sx"          "true"
+check 12  "ends_with_sx hello"              "false"
+check 13  "ends_with_sx empty"              "false"
+check 20  "section activity_types count"    "5"
+check 21  "section object_types count"      "13"
+check 22  "section projections count"       "7"
+check 23  "section validators count"        "3"
+check 24  "section codecs count"            "3"
+check 25  "section sig_suites count"        "2"
+check 26  "section audience count"          "3"
+check 30  "read_genesis returns 7 sections" "7"
+check 31  "first section name"              "activity_types"
+check 32  "first section entry count"       "5"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/bootstrap_read.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/bootstrap_start.sh

@@ -0,0 +1,134 @@
+#!/usr/bin/env bash
+# next/tests/bootstrap_start.sh — Step 4f-consolidate test.
+#
+# bootstrap:start/3 is the one-call kernel bring-up: starts the
+# registry gen_server, populates it from the genesis bundle,
+# and starts the nx_kernel gen_server. Each test inlines the
+# start call with downstream operations because spawned
+# processes don't survive across separate erlang-eval-ast calls.
+# 11 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+PRELUDE='KM = <<1,2,3,4>>, KS = [{key_id,k1},{algorithm,ed25519},{value,KM}], AS = [{public_keys,[[{id,k1},{created,0},{value,KM}]]}], bootstrap:start(alice, KS, AS),'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/projection.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/registry.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_kernel.erl\")) :name)")
+(epoch 10)
+(eval "(get (erlang-load-module (file-read \"next/kernel/bootstrap.erl\")) :name)")
+
+;; bootstrap:start returns a Pid
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${PRELUDE} is_pid(whereis(nx_kernel))\") :name)")
+
+;; Registry has 3 activity types after start
+(epoch 21)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(activity_types))\")")
+
+;; Registry has 10 object types
+(epoch 22)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(object_types))\")")
+
+;; Registry has 7 projections
+(epoch 23)
+(eval "(erlang-eval-ast \"${PRELUDE} length(registry:list(projections))\")")
+
+;; Total entries across all kinds = 31
+(epoch 24)
+(eval "(erlang-eval-ast \"${PRELUDE} L = lists:map(fun (K) -> length(registry:list(K)) end, registry:kinds()), lists:foldl(fun (X, A) -> X + A end, 0, L)\")")
+
+;; nx_kernel fresh log_tip = 0
+(epoch 25)
+(eval "(erlang-eval-ast \"${PRELUDE} nx_kernel:log_tip()\")")
+
+;; nx_kernel publish advances log_tip
+(epoch 26)
+(eval "(erlang-eval-ast \"${PRELUDE} nx_kernel:publish([{type, create}, {object, nil}]), nx_kernel:log_tip()\")")
+
+;; nx_kernel state carries the supplied actor_id
+(epoch 27)
+(eval "(get (erlang-eval-ast \"${PRELUDE} nx_kernel:actor_id(nx_kernel:query()) =:= alice\") :name)")
+
+;; Registry lookup works after start (canonical entry: Create)
+(epoch 28)
+(eval "(get (erlang-eval-ast \"${PRELUDE} case registry:lookup(activity_types, <<99,114,101,97,116,101>>) of {ok, _} -> ok; _ -> bad end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 600 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check 10  "bootstrap module loaded"           "bootstrap"
+check 20  "whereis(nx_kernel) is Pid"         "true"
+check 21  "activity_types count = 5"          "5"
+check 22  "object_types count = 13"           "13"
+check 23  "projections count = 7"             "7"
+check 24  "total entries = 36"                "36"
+check 25  "fresh log_tip = 0"                 "0"
+check 26  "publish advances tip to 1"         "1"
+check 27  "actor_id = alice"                  "true"
+check 28  "registry has create"               "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/bootstrap_start.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/cid.sh

@@ -0,0 +1,117 @@
+#!/usr/bin/env bash
+# next/tests/cid.sh — Step 1b acceptance test.
+#
+# Loads next/kernel/nx_cid.erl into the Erlang-on-SX runtime and checks
+# the canonical CID contract: determinism, uniqueness, equality, and
+# to_string/from_string round-trip. 12 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_cid.erl\")) :name)")
+
+;; from_sx returns a binary
+(epoch 10)
+(eval "(get (erlang-eval-ast \"is_binary(nx_cid:from_sx(foo))\") :name)")
+
+;; from_sx is deterministic on atoms / ints / compound terms
+(epoch 11)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx(foo) =:= nx_cid:from_sx(foo)\") :name)")
+(epoch 12)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx(42) =:= nx_cid:from_sx(42)\") :name)")
+(epoch 13)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx({a, [1, 2, 3]}) =:= nx_cid:from_sx({a, [1, 2, 3]})\") :name)")
+
+;; from_sx is collision-resistant on distinct terms
+(epoch 20)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx(foo) =/= nx_cid:from_sx(bar)\") :name)")
+(epoch 21)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx(1) =/= nx_cid:from_sx(2)\") :name)")
+(epoch 22)
+(eval "(get (erlang-eval-ast \"nx_cid:from_sx([1, 2]) =/= nx_cid:from_sx([1, 2, 3])\") :name)")
+
+;; equals/2 is alias for =:=
+(epoch 30)
+(eval "(get (erlang-eval-ast \"nx_cid:equals(nx_cid:from_sx(foo), nx_cid:from_sx(foo))\") :name)")
+(epoch 31)
+(eval "(get (erlang-eval-ast \"nx_cid:equals(nx_cid:from_sx(foo), nx_cid:from_sx(bar))\") :name)")
+
+;; to_string + from_string round-trip
+(epoch 40)
+(eval "(get (erlang-eval-ast \"nx_cid:equals(nx_cid:from_string(nx_cid:to_string(nx_cid:from_sx(foo))), nx_cid:from_sx(foo))\") :name)")
+(epoch 41)
+(eval "(get (erlang-eval-ast \"is_binary(nx_cid:to_string(nx_cid:from_sx({tuple, 1, 2})))\") :name)")
+
+;; CIDv1 raw codec sha256 base32 form is around 59 chars; sanity-check length
+(epoch 50)
+(eval "(get (erlang-eval-ast \"byte_size(nx_cid:from_sx(hello)) > 50\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                "nx_cid"
+check 10  "from_sx returns binary"          "true"
+check 11  "from_sx atom deterministic"      "true"
+check 12  "from_sx int deterministic"       "true"
+check 13  "from_sx compound deterministic"  "true"
+check 20  "from_sx atoms distinct"          "true"
+check 21  "from_sx ints distinct"           "true"
+check 22  "from_sx lists distinct"          "true"
+check 30  "equals same CIDs"                "true"
+check 31  "equals different CIDs"           "false"
+check 40  "to_string/from_string round-trip" "true"
+check 41  "to_string returns binary"        "true"
+check 50  "CIDv1 base32 length sanity"      "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/cid.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/define_registry_pure.sh

@@ -0,0 +1,139 @@
+#!/usr/bin/env bash
+# next/tests/define_registry_pure.sh — Step 5d-pure test.
+#
+# Exercises the Erlang-fun stand-in for the define-registry
+# projection fold. Activities flow: Create{Define*{...}} ->
+# registry:register/4 keyed by define_kind/1. 14 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/registry.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/projection.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/define_registry.erl\")) :name)")
+
+;; define_kind covers all seven kinds
+(epoch 10)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_activity) =:= activity_types\") :name)")
+(epoch 11)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_object) =:= object_types\") :name)")
+(epoch 12)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_projection) =:= projections\") :name)")
+(epoch 13)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_validator) =:= validators\") :name)")
+(epoch 14)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_codec) =:= codecs\") :name)")
+(epoch 15)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_sig_suite) =:= sig_suites\") :name)")
+(epoch 16)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(define_audience) =:= audience\") :name)")
+
+;; Unknown type returns not_a_define
+(epoch 17)
+(eval "(get (erlang-eval-ast \"define_registry:define_kind(some_other_type) =:= not_a_define\") :name)")
+
+;; Non-Create activity is a pass-through
+(epoch 20)
+(eval "(get (erlang-eval-ast \"define_registry:fold([{type, update}, {object, [{type, define_activity}, {name, pin}]}], registry:new()) =:= registry:new()\") :name)")
+
+;; Create{non-Define} is a pass-through
+(epoch 21)
+(eval "(get (erlang-eval-ast \"define_registry:fold([{type, create}, {object, [{type, note}, {name, x}]}], registry:new()) =:= registry:new()\") :name)")
+
+;; Create{Define*} without :name is a pass-through (preserves State)
+(epoch 22)
+(eval "(get (erlang-eval-ast \"define_registry:fold([{type, create}, {object, [{type, define_activity}]}], registry:new()) =:= registry:new()\") :name)")
+
+;; Happy path: Create{DefineActivity{name: pin}} registers under activity_types
+(epoch 23)
+(eval "(get (erlang-eval-ast \"Act = [{type, create}, {object, [{type, define_activity}, {name, pin}]}], S = define_registry:fold(Act, registry:new()), {ok, _} = registry:lookup(activity_types, pin, S), ok\") :name)")
+
+;; Multi-fold accumulates across kinds
+(epoch 24)
+(eval "(get (erlang-eval-ast \"A1 = [{type, create}, {object, [{type, define_activity}, {name, pin}]}], A2 = [{type, create}, {object, [{type, define_object}, {name, pin_spec}]}], A3 = [{type, create}, {object, [{type, define_projection}, {name, pin_state}]}], S = define_registry:fold(A3, define_registry:fold(A2, define_registry:fold(A1, registry:new()))), {length(registry:list(activity_types, S)), length(registry:list(object_types, S)), length(registry:list(projections, S))} =:= {1, 1, 1}\") :name)")
+
+;; Override: re-defining same name does not duplicate entry
+(epoch 25)
+(eval "(get (erlang-eval-ast \"A1 = [{type, create}, {object, [{type, define_activity}, {name, pin}, {v, 1}]}], A2 = [{type, create}, {object, [{type, define_activity}, {name, pin}, {v, 2}]}], S = define_registry:fold(A2, define_registry:fold(A1, registry:new())), case registry:lookup(activity_types, pin, S) of {ok, Entry} -> (length(registry:list(activity_types, S)) =:= 1) and (envelope:get_field(v, Entry) =:= {ok, 2}); _ -> false end\") :name)")
+
+;; Integration with the projection driver: define_registry as fold_fn
+(epoch 26)
+(eval "(get (erlang-eval-ast \"projection:start_link(dr, registry:new(), define_registry:fold_fn()), projection:async_fold(dr, [{type, create}, {object, [{type, define_activity}, {name, pin}]}]), S = projection:query(dr), case registry:lookup(activity_types, pin, S) of {ok, _} -> ok; _ -> bad end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  6  "define_registry module loaded"     "define_registry"
+check 10  "kind: define_activity"             "true"
+check 11  "kind: define_object"               "true"
+check 12  "kind: define_projection"           "true"
+check 13  "kind: define_validator"            "true"
+check 14  "kind: define_codec"                "true"
+check 15  "kind: define_sig_suite"            "true"
+check 16  "kind: define_audience"             "true"
+check 17  "kind: other -> not_a_define"       "true"
+check 20  "non-Create -> pass-through"        "true"
+check 21  "Create{non-Define} pass-through"   "true"
+check 22  "Define{} without :name no-op"      "true"
+check 23  "Create{DefineActivity} registers"  "ok"
+check 24  "multi-fold accumulates"            "true"
+check 25  "override preserves single entry"   "true"
+check 26  "projection integration"            "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/define_registry_pure.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/delivery_dispatch.sh

@@ -0,0 +1,120 @@
+#!/usr/bin/env bash
+# next/tests/delivery_dispatch.sh — m2 Step 8d test.
+#
+# After a successful outbox:publish, each ActorId in the
+# Result's :delivery_set is enqueued onto the matching
+# delivery_worker (registered under the peer-id atom). Only
+# happens when Context carries {dispatch_deliveries, true} —
+# back-compat with every M1 outbox caller that doesn't dispatch.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Alice publishes to bob (and carol). Each peer worker is registered
+# under its peer-id atom; the outbox dispatches via the workers'
+# enqueue path. dispatch_fn left undefined so the workers just
+# accumulate pending without firing HTTP.
+SETUP='K = <<1,2,3,4>>, KS = [{key_id,k1},{algorithm,ed25519},{value,K}], AS = [{public_keys,[[{id,k1},{created,0},{value,K}]]}], {ok, L0} = log:open(alice, <<98,97,115,101>>), Ctx = [{actor_id,alice},{published,1},{key_spec,KS},{actor_state,AS},{log,L0},{projections,[]},{dispatch_deliveries, true}], CtxNoDispatch = [{actor_id,alice},{published,1},{key_spec,KS},{actor_state,AS},{log,L0},{projections,[]}], ReqToBob = [{type, note}, {object, [{content, hi}]}, {to, bob}], ReqToTwo = [{type, note}, {object, [{content, hi}]}, {to, [bob, carol]}],'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_worker.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+
+;; Bob's worker registered + publish to bob -> bob's pending has 1 entry
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), {ok, _, _} = outbox:publish(ReqToBob, Ctx), case delivery_worker:pending_srv(bob) of [_] -> ok; _ -> bad end\") :name)")
+
+;; Carol's worker registered, publish to [bob, carol] -> both queues get 1 entry
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), delivery_worker:start_link(carol), {ok, _, _} = outbox:publish(ReqToTwo, Ctx), {length(delivery_worker:pending_srv(bob)), length(delivery_worker:pending_srv(carol))} =:= {1, 1}\") :name)")
+
+;; Missing worker for an actor in delivery_set -> silently skipped (no error)
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), case outbox:publish(ReqToTwo, Ctx) of {ok, R, _} -> envelope:get_field(delivery_set, R) =:= {ok, [bob, carol]}; _ -> false end andalso length(delivery_worker:pending_srv(bob)) =:= 1\") :name)")
+
+;; No :dispatch_deliveries flag -> no enqueue happens (back-compat)
+(epoch 23)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), {ok, _, _} = outbox:publish(ReqToBob, CtxNoDispatch), delivery_worker:pending_srv(bob) =:= []\") :name)")
+
+;; Two publishes -> bob's queue has 2 entries (FIFO append)
+(epoch 24)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), {ok, _, NewLog} = outbox:publish(ReqToBob, Ctx), Ctx2 = [{actor_id,alice},{published,2},{key_spec,KS},{actor_state,AS},{log,NewLog},{projections,[]},{dispatch_deliveries, true}], {ok, _, _} = outbox:publish(ReqToBob, Ctx2), length(delivery_worker:pending_srv(bob)) =:= 2\") :name)")
+
+;; Empty delivery_set -> no dispatch (no :to, no :cc)
+(epoch 25)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), ReqNoAud = [{type, note}, {object, [{content, hi}]}], {ok, _, _} = outbox:publish(ReqNoAud, Ctx), delivery_worker:pending_srv(bob) =:= []\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 540 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  9  "outbox module loaded"           "outbox"
+check 20  "single peer enqueued"           "ok"
+check 21  "two peers both enqueued"        "true"
+check 22  "missing worker silently skip"   "true"
+check 23  "no dispatch_deliveries no-op"   "true"
+check 24  "two publishes FIFO append"      "true"
+check 25  "empty delivery_set -> no-op"    "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/delivery_dispatch.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/delivery_retry.sh

@@ -0,0 +1,126 @@
+#!/usr/bin/env bash
+# next/tests/delivery_retry.sh — m2 Step 8b-pure test.
+#
+# Pure-functional retry-time bookkeeping for the delivery worker.
+# record_failure bumps the attempt counter and computes the next
+# retry time per backoff_for. record_success clears state for a
+# cid. next_due returns cids whose retry time has passed.
+#
+# Real timer wiring (erlang:send_after self-cast) is Step 8b-timer
+# once substrate support lands.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+SETUP='Act1 = [{id, <<1>>}, {type, note}, {actor, alice}], Act2 = [{id, <<2>>}, {type, note}, {actor, alice}],'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_worker.erl\")) :name)")
+
+;; Fresh state: no attempts, no next_retry, no dead_letter
+(epoch 10)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_worker:new(bob), {delivery_worker:attempts_for(<<1>>, S), delivery_worker:next_retry_at(<<1>>, S), delivery_worker:dead_letter_list(S)} =:= {0, undefined, []}\") :name)")
+
+;; record_failure bumps the attempt counter
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), delivery_worker:attempts_for(<<1>>, S1) =:= 1\") :name)")
+
+;; record_failure sets next_retry_at = Now + backoff(1) = Now + 30
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), delivery_worker:next_retry_at(<<1>>, S1) =:= 1030\") :name)")
+
+;; Second failure -> attempts=2, NextRetryAt = Now+300
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), S2 = delivery_worker:record_failure_pure(<<1>>, 2000, S1), {delivery_worker:attempts_for(<<1>>, S2), delivery_worker:next_retry_at(<<1>>, S2)} =:= {2, 2300}\") :name)")
+
+;; record_success clears attempts + next_retry for the cid
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), S2 = delivery_worker:record_success_pure(<<1>>, S1), {delivery_worker:attempts_for(<<1>>, S2), delivery_worker:next_retry_at(<<1>>, S2)} =:= {0, undefined}\") :name)")
+
+;; next_due returns Cids whose retry time has passed
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), delivery_worker:next_due_pure(1030, S1) =:= [<<1>>]\") :name)")
+
+;; next_due returns [] before retry time
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), delivery_worker:next_due_pure(1020, S1) =:= []\") :name)")
+
+;; 6th failure -> dead_letter; activity moves out of :pending
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${SETUP} F = fun(S) -> delivery_worker:record_failure_pure(<<1>>, 1000, S) end, S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S6 = F(F(F(F(F(F(S0)))))), {delivery_worker:dead_letter_list(S6), delivery_worker:pending(S6)} =:= {[Act1], []}\") :name)")
+
+;; Dead-lettered cid is no longer in next_retry
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${SETUP} F = fun(S) -> delivery_worker:record_failure_pure(<<1>>, 1000, S) end, S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), S6 = F(F(F(F(F(F(S0)))))), delivery_worker:next_retry_at(<<1>>, S6) =:= undefined\") :name)")
+
+;; Two cids: success on one doesn't disturb the other's retry state
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:enqueue_pure(bob, Act2, delivery_worker:new(bob))), S1 = delivery_worker:record_failure_pure(<<1>>, 1000, S0), S2 = delivery_worker:record_failure_pure(<<2>>, 1000, S1), S3 = delivery_worker:record_success_pure(<<1>>, S2), delivery_worker:next_retry_at(<<2>>, S3) =:= 1030\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  3  "module loaded"                      "delivery_worker"
+check 10  "fresh state empty"                  "true"
+check 11  "record_failure bumps attempts"      "true"
+check 12  "record_failure sets next_retry_at"  "true"
+check 13  "second failure: slot 2 = +300"      "true"
+check 14  "record_success clears state"        "true"
+check 15  "next_due returns due cids"          "true"
+check 16  "next_due empty before due"          "true"
+check 17  "6th failure -> dead_letter"         "true"
+check 18  "dead-lettered cid out of retry"     "true"
+check 19  "success on one preserves other"     "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/delivery_retry.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/delivery_set.sh

@@ -0,0 +1,164 @@
+#!/usr/bin/env bash
+# next/tests/delivery_set.sh — m2 Step 7 test.
+#
+# delivery:delivery_set/2,3 computes the audience-resolved
+# recipient list for an outbound activity. Sources are :to / :cc
+# fields plus expansion of `followers` (via follower_graph) and
+# `public` (v2 placeholder — Step 7c will populate with peer
+# instances). Self-delivery suppressed; result deduplicated.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery.erl\")) :name)")
+
+;; Empty activity -> empty delivery set
+(epoch 10)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}], []) =:= []\") :name)")
+
+;; Single :to atom recipient
+(epoch 11)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, bob}], []) =:= [bob]\") :name)")
+
+;; :to list of recipients
+(epoch 12)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, [bob, carol]}], []) =:= [bob, carol]\") :name)")
+
+;; :cc adds to :to
+(epoch 13)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, [bob]}, {cc, [carol]}], []) =:= [bob, carol]\") :name)")
+
+;; Self-delivery suppressed (alice in :to is the publisher)
+(epoch 14)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, [alice, bob]}], []) =:= [bob]\") :name)")
+
+;; Duplicate recipients deduped
+(epoch 15)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, [bob, bob]}, {cc, [bob]}], []) =:= [bob]\") :name)")
+
+;; :to and :cc with overlap are deduped
+(epoch 16)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, [bob, carol]}, {cc, [carol, dave]}], []) =:= [bob, carol, dave]\") :name)")
+
+;; followers audience symbol -> sender's followers from follower_graph
+(epoch 17)
+(eval "(get (erlang-eval-ast \"Follow = [{actor, bob}, {type, follow}, {object, alice}], Accept = [{actor, alice}, {type, accept}, {object, Follow}], S = follower_graph:fold(Accept, follower_graph:fold(Follow, follower_graph:new())), delivery:delivery_set([{actor, alice}, {to, followers}], [], S) =:= [bob]\") :name)")
+
+;; followers with empty follower-graph -> []
+(epoch 18)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, followers}], [], follower_graph:new()) =:= []\") :name)")
+
+;; public audience symbol -> sender's followers for v2 (§13.4)
+(epoch 19)
+(eval "(get (erlang-eval-ast \"F = [{actor, bob}, {type, follow}, {object, alice}], A = [{actor, alice}, {type, accept}, {object, F}], S = follower_graph:fold(A, follower_graph:fold(F, follower_graph:new())), delivery:delivery_set([{actor, alice}, {to, public}], [], S) =:= [bob]\") :name)")
+
+;; public with empty follower-graph -> []
+(epoch 28)
+(eval "(get (erlang-eval-ast \"delivery:delivery_set([{actor, alice}, {to, public}], [], follower_graph:new()) =:= []\") :name)")
+
+;; public + followers in same audience deduped (both expand identically)
+(epoch 29)
+(eval "(get (erlang-eval-ast \"F = [{actor, bob}, {type, follow}, {object, alice}], A = [{actor, alice}, {type, accept}, {object, F}], S = follower_graph:fold(A, follower_graph:fold(F, follower_graph:new())), delivery:delivery_set([{actor, alice}, {to, [public, followers]}], [], S) =:= [bob]\") :name)")
+
+;; Mixed explicit + followers, followers carry two peers
+(epoch 20)
+(eval "(get (erlang-eval-ast \"F1 = [{actor, bob}, {type, follow}, {object, alice}], A1 = [{actor, alice}, {type, accept}, {object, F1}], F2 = [{actor, carol}, {type, follow}, {object, alice}], A2 = [{actor, alice}, {type, accept}, {object, F2}], S = follower_graph:fold(A2, follower_graph:fold(F2, follower_graph:fold(A1, follower_graph:fold(F1, follower_graph:new())))), delivery:delivery_set([{actor, alice}, {to, [dave, followers]}], [], S) =:= [dave, bob, carol]\") :name)")
+
+;; followers + explicit, with overlap deduped
+(epoch 21)
+(eval "(get (erlang-eval-ast \"F = [{actor, bob}, {type, follow}, {object, alice}], A = [{actor, alice}, {type, accept}, {object, F}], S = follower_graph:fold(A, follower_graph:fold(F, follower_graph:new())), delivery:delivery_set([{actor, alice}, {to, [bob, followers]}], [], S) =:= [bob]\") :name)")
+
+;; collect_recipients: bare helper returns flat list (no dedup, no self-suppression)
+(epoch 22)
+(eval "(get (erlang-eval-ast \"delivery:collect_recipients([{actor, alice}, {to, [bob, carol]}, {cc, [carol, dave]}]) =:= [bob, carol, carol, dave]\") :name)")
+
+;; suppress_self drops every occurrence of Self
+(epoch 23)
+(eval "(get (erlang-eval-ast \"delivery:suppress_self([bob, alice, carol, alice], alice) =:= [bob, carol]\") :name)")
+
+;; dedup preserves first occurrence order
+(epoch 24)
+(eval "(get (erlang-eval-ast \"delivery:dedup([bob, carol, bob, dave, carol]) =:= [bob, carol, dave]\") :name)")
+
+;; expand_audience: pass-through for plain ActorId
+(epoch 25)
+(eval "(get (erlang-eval-ast \"delivery:expand_audience(carol, alice, follower_graph:new()) =:= [carol]\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  4  "delivery module loaded"           "delivery"
+check 10  "empty activity -> empty set"      "true"
+check 11  "single :to atom recipient"        "true"
+check 12  "list :to recipients"              "true"
+check 13  ":to + :cc unioned"                "true"
+check 14  "self-delivery suppressed"         "true"
+check 15  "duplicates within :to deduped"    "true"
+check 16  ":to/:cc overlap deduped"          "true"
+check 17  "followers expands via graph"      "true"
+check 18  "empty follower-graph -> []"       "true"
+check 19  "public -> sender's followers"     "true"
+check 28  "public empty graph -> []"         "true"
+check 29  "public + followers dedupe"        "true"
+check 20  "mixed explicit + followers"       "true"
+check 21  "followers + overlap deduped"      "true"
+check 22  "collect_recipients raw flat"      "true"
+check 23  "suppress_self drops every match"  "true"
+check 24  "dedup preserves first-occurrence" "true"
+check 25  "expand_audience pass-through"     "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/delivery_set.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/delivery_state.sh

@@ -0,0 +1,139 @@
+#!/usr/bin/env bash
+# next/tests/delivery_state.sh — m2 Step 8c test.
+#
+# Delivery-state projection: folds enqueue / delivered / failed /
+# dead_lettered events into a per-peer worker-shaped snapshot so
+# the outbound queue survives kernel restart.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+SETUP='Act1 = [{id, <<1>>}, {type, note}, {actor, alice}], Act2 = [{id, <<2>>}, {type, note}, {actor, alice}], E_Enq1 = [{type, enqueued}, {peer, bob}, {activity, Act1}], E_Enq2 = [{type, enqueued}, {peer, bob}, {activity, Act2}], E_Enq2Carol = [{type, enqueued}, {peer, carol}, {activity, Act2}], E_Del1 = [{type, delivered}, {peer, bob}, {cid, <<1>>}], E_Fail1 = [{type, failed}, {peer, bob}, {cid, <<1>>}, {now, 1000}],'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_worker.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_state.erl\")) :name)")
+
+;; Fresh projection -> []
+(epoch 10)
+(eval "(get (erlang-eval-ast \"delivery_state:new() =:= []\") :name)")
+
+;; enqueued event creates a peer entry and appends to pending
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Enq1, delivery_state:new()), delivery_state:pending(bob, S) =:= [Act1]\") :name)")
+
+;; Two enqueues to same peer -> FIFO order
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Enq2, delivery_state:fold(E_Enq1, delivery_state:new())), delivery_state:pending(bob, S) =:= [Act1, Act2]\") :name)")
+
+;; Enqueues to different peers -> independent queues
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Enq2Carol, delivery_state:fold(E_Enq1, delivery_state:new())), {delivery_state:pending(bob, S), delivery_state:pending(carol, S)} =:= {[Act1], [Act2]}\") :name)")
+
+;; delivered event clears the matching pending entry
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Del1, delivery_state:fold(E_Enq1, delivery_state:new())), delivery_state:pending(bob, S) =:= []\") :name)")
+
+;; failed event bumps attempts and sets next_retry
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Fail1, delivery_state:fold(E_Enq1, delivery_state:new())), {delivery_state:attempts(bob, S), delivery_state:next_retry(bob, S)} =:= {[{<<1>>, 1}], [{<<1>>, 1030}]}\") :name)")
+
+;; Five failures then 6th fails -> dead_lettered
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${SETUP} F = fun(S) -> delivery_state:fold(E_Fail1, S) end, S0 = delivery_state:fold(E_Enq1, delivery_state:new()), S6 = F(F(F(F(F(F(S0)))))), {delivery_state:dead_letter(bob, S6), delivery_state:pending(bob, S6)} =:= {[Act1], []}\") :name)")
+
+;; Explicit dead_lettered event moves activity to dead_letter
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${SETUP} E_DL = [{type, dead_lettered}, {peer, bob}, {cid, <<1>>}], S = delivery_state:fold(E_DL, delivery_state:fold(E_Enq1, delivery_state:new())), {delivery_state:dead_letter(bob, S), delivery_state:pending(bob, S)} =:= {[Act1], []}\") :name)")
+
+;; peers/1 lists every peer touched
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Enq2Carol, delivery_state:fold(E_Enq1, delivery_state:new())), delivery_state:peers(S) =:= [bob, carol]\") :name)")
+
+;; peer_state returns {ok, Worker} | not_found
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Enq1, delivery_state:new()), case delivery_state:peer_state(bob, S) of {ok, _} -> true; _ -> false end andalso delivery_state:peer_state(ghost, S) =:= not_found\") :name)")
+
+;; fold_fn/0 returns a 2-arity Erlang fun usable by projection:start_link/3
+(epoch 20)
+(eval "(get (erlang-eval-ast \"is_function(delivery_state:fold_fn(), 2)\") :name)")
+
+;; Unknown event type passes through
+(epoch 21)
+(eval "(get (erlang-eval-ast \"Garbage = [{type, mystery}, {peer, bob}], delivery_state:fold(Garbage, delivery_state:new()) =:= []\") :name)")
+
+;; delivered after failed clears retry state
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_state:fold(E_Del1, delivery_state:fold(E_Fail1, delivery_state:fold(E_Enq1, delivery_state:new()))), {delivery_state:attempts(bob, S), delivery_state:next_retry(bob, S)} =:= {[], []}\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  4  "delivery_state module loaded"     "delivery_state"
+check 10  "new/0 -> []"                      "true"
+check 11  "enqueued -> pending appended"     "true"
+check 12  "two enqueues -> FIFO"             "true"
+check 13  "two peers independent queues"     "true"
+check 14  "delivered clears pending entry"   "true"
+check 15  "failed bumps attempts + next_retry" "true"
+check 16  "6th failed -> dead_lettered"      "true"
+check 17  "explicit dead_lettered event"     "true"
+check 18  "peers/1 lists touched"            "true"
+check 19  "peer_state ok / not_found"        "true"
+check 20  "fold_fn/0 is fun/2"               "true"
+check 21  "unknown event passes through"     "true"
+check 22  "delivered after failed clears"    "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/delivery_state.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/delivery_worker.sh

@@ -0,0 +1,156 @@
+#!/usr/bin/env bash
+# next/tests/delivery_worker.sh — m2 Step 8a test.
+#
+# Pure-functional state shape + gen_server skeleton for the
+# outbound delivery worker. One worker per peer; FIFO queue of
+# pending activities; caller-supplied :dispatch_fn does the actual
+# HTTP POST (stubbed for tests, live httpc in Step 8f). Retry /
+# backoff (Step 8b) and persist-survival (Step 8c) layer on top.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+SETUP='Act1 = [{id, <<1,2,3>>}, {type, note}, {actor, alice}], Act2 = [{id, <<4,5,6>>}, {type, note}, {actor, alice}], OkFetch = fun(_) -> ok end, FailFetch = fun(_) -> {error, http_500} end,'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/delivery_worker.erl\")) :name)")
+
+;; new/1 returns initial state with empty queue
+(epoch 10)
+(eval "(get (erlang-eval-ast \"delivery_worker:pending(delivery_worker:new(bob)) =:= []\") :name)")
+
+;; peer/1 reads the peer id
+(epoch 11)
+(eval "(get (erlang-eval-ast \"delivery_worker:peer(delivery_worker:new(bob)) =:= bob\") :name)")
+
+;; enqueue_pure appends to the queue
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${SETUP} S = delivery_worker:enqueue_pure(bob, Act1, delivery_worker:new(bob)), delivery_worker:pending(S) =:= [Act1]\") :name)")
+
+;; Two enqueues -> FIFO order
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:new(bob), S1 = delivery_worker:enqueue_pure(bob, Act1, S0), S2 = delivery_worker:enqueue_pure(bob, Act2, S1), delivery_worker:pending(S2) =:= [Act1, Act2]\") :name)")
+
+;; drain_pure with no dispatch_fn -> all retry, queue intact
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:new(bob), S1 = delivery_worker:enqueue_pure(bob, Act1, S0), {S2, Delivered, Retry} = delivery_worker:drain_pure(S1), Delivered =:= [] andalso length(Retry) =:= 1 andalso delivery_worker:pending(S2) =:= [Act1]\") :name)")
+
+;; drain_pure with success dispatch -> activities cleared
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${SETUP} S0 = delivery_worker:new(bob), S1 = lists:foldl(fun(K, A) -> delivery_worker:enqueue_pure(bob, K, A) end, S0, [Act1, Act2]), Wired = [{peer, bob}, {pending, [Act1, Act2]}, {attempts, []}, {dead_letter, []}, {dispatch_fn, OkFetch}], {S2, Delivered, Retry} = delivery_worker:drain_pure(Wired), delivery_worker:pending(S2) =:= [] andalso length(Delivered) =:= 2 andalso Retry =:= []\") :name)")
+
+;; drain_pure with failing dispatch -> activities stay; attempt counter bumped
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${SETUP} Wired = [{peer, bob}, {pending, [Act1]}, {attempts, []}, {dead_letter, []}, {dispatch_fn, FailFetch}], {S, Delivered, Retry} = delivery_worker:drain_pure(Wired), delivery_worker:pending(S) =:= [Act1] andalso Delivered =:= [] andalso length(Retry) =:= 1\") :name)")
+
+;; deliver_one_pure success returns {ok, Cid}
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${SETUP} Wired = [{peer, bob}, {pending, []}, {attempts, []}, {dead_letter, []}, {dispatch_fn, OkFetch}], case delivery_worker:deliver_one_pure(Act1, Wired) of {ok, <<1,2,3>>} -> ok; _ -> bad end\") :name)")
+
+;; deliver_one_pure with no dispatch_fn returns no_dispatch_fn
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${SETUP} case delivery_worker:deliver_one_pure(Act1, delivery_worker:new(bob)) of {error, _, no_dispatch_fn} -> ok; _ -> bad end\") :name)")
+
+;; backoff_for slots match the design schedule
+(epoch 19)
+(eval "(get (erlang-eval-ast \"{delivery_worker:backoff_for(1), delivery_worker:backoff_for(2), delivery_worker:backoff_for(3), delivery_worker:backoff_for(4), delivery_worker:backoff_for(5)} =:= {30, 300, 1800, 21600, 86400}\") :name)")
+
+;; backoff_for(>=6) returns dead_letter
+(epoch 20)
+(eval "(get (erlang-eval-ast \"delivery_worker:backoff_for(6) =:= dead_letter\") :name)")
+
+;; schedule_for returns {retry_in, Sec} or dead_letter
+(epoch 21)
+(eval "(get (erlang-eval-ast \"{delivery_worker:schedule_for(1), delivery_worker:schedule_for(6)} =:= {{retry_in, 30}, dead_letter}\") :name)")
+
+;; gen_server: start_link + enqueue + pending_srv
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), delivery_worker:enqueue(bob, Act1), delivery_worker:pending_srv(bob) =:= [Act1]\") :name)")
+
+;; gen_server: flush with dispatch_fn -> {ok, [Cid], []}
+(epoch 23)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob, OkFetch), delivery_worker:enqueue(bob, Act1), case delivery_worker:flush(bob) of {ok, [<<1,2,3>>], []} -> ok; _ -> bad end\") :name)")
+
+;; gen_server: flush with failing dispatch -> {ok, [], [Cid]}, queue stays
+(epoch 24)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob, FailFetch), delivery_worker:enqueue(bob, Act1), case delivery_worker:flush(bob) of {ok, [], [<<1,2,3>>]} -> ok; _ -> bad end andalso delivery_worker:pending_srv(bob) =:= [Act1]\") :name)")
+
+;; gen_server: set_dispatch_fn swaps the function in-flight
+(epoch 25)
+(eval "(get (erlang-eval-ast \"${SETUP} delivery_worker:start_link(bob), delivery_worker:enqueue(bob, Act1), delivery_worker:set_dispatch_fn(bob, OkFetch), case delivery_worker:flush(bob) of {ok, [<<1,2,3>>], []} -> ok; _ -> bad end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 360 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  4  "delivery_worker module loaded"  "delivery_worker"
+check 10  "new/1 -> empty queue"           "true"
+check 11  "peer/1 reads peer id"           "true"
+check 12  "enqueue_pure appends"           "true"
+check 13  "FIFO order preserved"           "true"
+check 14  "drain w/o dispatch -> retry"    "true"
+check 15  "drain ok clears queue"          "true"
+check 16  "drain fail keeps queue"         "true"
+check 17  "deliver_one ok -> {ok, Cid}"    "ok"
+check 18  "deliver_one no fn -> err"       "ok"
+check 19  "backoff schedule matches plan"  "true"
+check 20  "backoff overflow -> dead"       "true"
+check 21  "schedule_for shape"             "true"
+check 22  "gen_server enqueue + pending"   "true"
+check 23  "gen_server flush ok"            "ok"
+check 24  "gen_server flush fail keeps"    "ok"
+check 25  "gen_server set_dispatch_fn"     "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/delivery_worker.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/discovery.sh

@@ -0,0 +1,124 @@
+#!/usr/bin/env bash
+# next/tests/discovery.sh — m2 Step 10a test.
+#
+# Local-side webfinger primitives: parse acct: URIs, synthesise
+# actor URLs, build the RFC 7033 webfinger JSON body.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/discovery.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; parse_acct accepts the acct: prefix form
+(epoch 10)
+(eval "(get (erlang-eval-ast \"discovery:parse_acct(<<97,99,99,116,58,97,108,105,99,101,64,104,111,115,116>>) =:= {ok, <<97,108,105,99,101>>, <<104,111,115,116>>}\") :name)")
+
+;; parse_acct accepts the bare form
+(epoch 11)
+(eval "(get (erlang-eval-ast \"discovery:parse_acct(<<97,108,105,99,101,64,104,111,115,116>>) =:= {ok, <<97,108,105,99,101>>, <<104,111,115,116>>}\") :name)")
+
+;; parse_acct host with port
+(epoch 12)
+(eval "(get (erlang-eval-ast \"discovery:parse_acct(<<97,108,105,99,101,64,104,111,115,116,58,57,57,57,57>>) =:= {ok, <<97,108,105,99,101>>, <<104,111,115,116,58,57,57,57,57>>}\") :name)")
+
+;; parse_acct rejects empty user
+(epoch 13)
+(eval "(get (erlang-eval-ast \"case discovery:parse_acct(<<64,104,111,115,116>>) of {error, _} -> true; _ -> false end\") :name)")
+
+;; parse_acct rejects missing @
+(epoch 14)
+(eval "(get (erlang-eval-ast \"case discovery:parse_acct(<<97,108,105,99,101>>) of {error, _} -> true; _ -> false end\") :name)")
+
+;; parse_acct rejects empty host
+(epoch 15)
+(eval "(get (erlang-eval-ast \"case discovery:parse_acct(<<97,108,105,99,101,64>>) of {error, _} -> true; _ -> false end\") :name)")
+
+;; parse_resource is an alias for parse_acct
+(epoch 16)
+(eval "(get (erlang-eval-ast \"discovery:parse_resource(<<97,99,99,116,58,98,111,98,64,98,46,99,111,109>>) =:= {ok, <<98,111,98>>, <<98,46,99,111,109>>}\") :name)")
+
+;; actor_url_for synthesises http://<host>/actors/<user>
+(epoch 17)
+(eval "(get (erlang-eval-ast \"discovery:actor_url_for(<<97,108,105,99,101>>, <<104,111,115,116>>) =:= <<104,116,116,112,58,47,47,104,111,115,116,47,97,99,116,111,114,115,47,97,108,105,99,101>>\") :name)")
+
+;; actor_url_for preserves port in host
+(epoch 18)
+(eval "(get (erlang-eval-ast \"discovery:actor_url_for(<<98,111,98>>, <<104,58,57,57>>) =:= <<104,116,116,112,58,47,47,104,58,57,57,47,97,99,116,111,114,115,47,98,111,98>>\") :name)")
+
+;; webfinger_body starts with {"subject":"acct:<user>@<host>" — http_server:match_prefix
+(epoch 19)
+(eval "(get (erlang-eval-ast \"B = discovery:webfinger_body(<<97,108,105,99,101>>, <<104,111,115,116>>, <<117,114,108>>), Pre = <<123,34,115,117,98,106,101,99,116,34,58,34,97,99,99,116,58,97,108,105,99,101,64,104,111,115,116,34>>, http_server:match_prefix(Pre, B) =/= nomatch\") :name)")
+
+;; webfinger_body byte_size is at least subject+links length (sanity)
+(epoch 20)
+(eval "(get (erlang-eval-ast \"B = discovery:webfinger_body(<<97,108,105,99,101>>, <<104,111,115,116>>, <<117,114,108>>), byte_size(B) > 80\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 480 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "discovery module loaded"          "discovery"
+check 10  "parse_acct prefixed"              "true"
+check 11  "parse_acct bare form"             "true"
+check 12  "parse_acct host with port"        "true"
+check 13  "parse_acct empty user -> error"   "true"
+check 14  "parse_acct missing @ -> error"    "true"
+check 15  "parse_acct empty host -> error"   "true"
+check 16  "parse_resource alias"             "true"
+check 17  "actor_url_for synthesises"        "true"
+check 18  "actor_url_for preserves port"     "true"
+check 19  "webfinger_body subject prefix"    "true"
+check 20  "webfinger_body has body bytes"    "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/discovery.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/envelope_canonical.sh

@@ -0,0 +1,105 @@
+#!/usr/bin/env bash
+# next/tests/envelope_canonical.sh — Step 2b acceptance test.
+#
+# Loads next/kernel/envelope.erl and checks canonical_bytes/1 contract:
+# returns a binary, deterministic across runs, invariant under
+# field-order permutation, invariant under signature changes, and
+# different for different covered content. 7 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+
+;; canonical_bytes returns a binary
+(epoch 10)
+(eval "(get (erlang-eval-ast \"is_binary(envelope:canonical_bytes([{id,1},{type,create},{actor,alice},{published,1000},{signature,whatever}]))\") :name)")
+
+;; Determinism: same envelope twice -> same bytes
+(epoch 11)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice}]) =:= envelope:canonical_bytes([{id,1},{type,create},{actor,alice}])\") :name)")
+
+;; Signature stripping: different signatures -> same canonical bytes
+(epoch 12)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice},{signature,sig_one}]) =:= envelope:canonical_bytes([{id,1},{type,create},{actor,alice},{signature,sig_two}])\") :name)")
+
+;; No signature vs some signature -> same canonical bytes
+(epoch 13)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice}]) =:= envelope:canonical_bytes([{id,1},{type,create},{actor,alice},{signature,whatever}])\") :name)")
+
+;; Key-order invariance: reordering top-level fields -> same bytes
+(epoch 14)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice}]) =:= envelope:canonical_bytes([{actor,alice},{type,create},{id,1}])\") :name)")
+
+;; Changing a covered field changes the bytes
+(epoch 15)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice}]) =/= envelope:canonical_bytes([{id,2},{type,create},{actor,alice}])\") :name)")
+
+;; Distinct envelopes -> distinct bytes
+(epoch 16)
+(eval "(get (erlang-eval-ast \"envelope:canonical_bytes([{id,1},{type,create},{actor,alice}]) =/= envelope:canonical_bytes([{id,1},{type,update},{actor,bob}])\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                "envelope"
+check 10  "canonical_bytes returns binary"  "true"
+check 11  "deterministic"                   "true"
+check 12  "signature stripped (changes)"    "true"
+check 13  "signature stripped (absent)"     "true"
+check 14  "key-order invariant"             "true"
+check 15  "covered field change visible"    "true"
+check 16  "distinct envelopes distinct"     "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/envelope_canonical.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/envelope_shape.sh

@@ -0,0 +1,126 @@
+#!/usr/bin/env bash
+# next/tests/envelope_shape.sh — Step 2a acceptance test.
+#
+# Loads next/kernel/envelope.erl into the Erlang-on-SX runtime and
+# checks validate_shape/1 / get_field/2 against the design §3.1 shape
+# contract. 13 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+
+;; Reusable valid envelope as Erlang text. The signature itself is a
+;; property list with key_id, algorithm, value.
+;;   E0 = [{id,1},{type,create},{actor,alice},{published,1000},
+;;         {signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]
+
+;; Complete valid envelope
+(epoch 10)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000},{signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]) =:= ok\") :name)")
+
+;; Missing each top-level required field
+(epoch 11)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{type,create},{actor,alice},{published,1000},{signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]) =:= {error,{missing_field,id}}\") :name)")
+(epoch 12)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{actor,alice},{published,1000},{signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]) =:= {error,{missing_field,type}}\") :name)")
+(epoch 13)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{published,1000},{signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]) =:= {error,{missing_field,actor}}\") :name)")
+(epoch 14)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{signature,[{key_id,k1},{algorithm,ed25519},{value,v}]}]) =:= {error,{missing_field,published}}\") :name)")
+(epoch 15)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000}]) =:= {error,{missing_field,signature}}\") :name)")
+
+;; Non-list inputs
+(epoch 16)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape(42) =:= {error,not_a_proplist}\") :name)")
+(epoch 17)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape(some_atom) =:= {error,not_a_proplist}\") :name)")
+
+;; Signature sub-shape
+(epoch 20)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000},{signature,[{algorithm,ed25519},{value,v}]}]) =:= {error,{bad_signature,{missing_field,key_id}}}\") :name)")
+(epoch 21)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000},{signature,[{key_id,k1},{value,v}]}]) =:= {error,{bad_signature,{missing_field,algorithm}}}\") :name)")
+(epoch 22)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000},{signature,[{key_id,k1},{algorithm,ed25519}]}]) =:= {error,{bad_signature,{missing_field,value}}}\") :name)")
+(epoch 23)
+(eval "(get (erlang-eval-ast \"envelope:validate_shape([{id,1},{type,create},{actor,alice},{published,1000},{signature,not_a_proplist}]) =:= {error,{bad_signature,not_a_proplist}}\") :name)")
+
+;; get_field
+(epoch 30)
+(eval "(get (erlang-eval-ast \"envelope:get_field(actor,[{id,1},{actor,alice}]) =:= {ok,alice}\") :name)")
+(epoch 31)
+(eval "(get (erlang-eval-ast \"envelope:get_field(missing,[{id,1},{actor,alice}]) =:= not_found\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                  "envelope"
+check 10  "complete envelope -> ok"           "true"
+check 11  "missing id"                        "true"
+check 12  "missing type"                      "true"
+check 13  "missing actor"                     "true"
+check 14  "missing published"                 "true"
+check 15  "missing signature"                 "true"
+check 16  "non-list (integer)"                "true"
+check 17  "non-list (atom)"                   "true"
+check 20  "signature missing key_id"          "true"
+check 21  "signature missing algorithm"       "true"
+check 22  "signature missing value"           "true"
+check 23  "signature not a proplist"          "true"
+check 30  "get_field hit"                     "true"
+check 31  "get_field miss"                    "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/envelope_shape.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/envelope_sig.sh

@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+# next/tests/envelope_sig.sh — Step 2c acceptance test.
+#
+# Exercises envelope:verify_signature/2 against the full sig pipeline:
+# canonical_bytes + crypto:hash MAC + time-aware key validity per design
+# §9.6. 10 cases.
+#
+# The signature stand-in is HMAC-shaped:
+#   sig.value = crypto:hash(sha256, <<KeyMaterial/binary, CanonicalBytes/binary>>)
+# Real Ed25519/RSA verification is deferred to milestone 2 once the
+# corresponding crypto BIFs are wired.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Shared Erlang prelude builds a valid-signed envelope template and an
+# actor state with one active key. Each test reuses these and asserts
+# against an Erlang =:= comparison so the result is a bare boolean.
+PRELUDE='KM = <<1,2,3,4>>, U = [{actor,alice},{id,1},{published,100},{type,create}], CB = envelope:canonical_bytes(U), Sig = crypto:hash(sha256, <<KM/binary, CB/binary>>), Env = [{actor,alice},{id,1},{published,100},{type,create},{signature,[{algorithm,ed25519},{key_id,k1},{value,Sig}]}], AS = [{public_keys, [[{id,k1},{created,50},{value,KM}]]}],'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+
+;; valid sig + active key -> ok
+(epoch 10)
+(eval "(get (erlang-eval-ast \"${PRELUDE} envelope:verify_signature(Env, AS) =:= ok\") :name)")
+
+;; tampered envelope (id mutated post-sign) -> bad_signature
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${PRELUDE} Tampered = [{actor,alice},{id,999},{published,100},{type,create},{signature,[{algorithm,ed25519},{key_id,k1},{value,Sig}]}], envelope:verify_signature(Tampered, AS) =:= {error,bad_signature}\") :name)")
+
+;; wrong sig value (random bytes) -> bad_signature
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${PRELUDE} BadEnv = [{actor,alice},{id,1},{published,100},{type,create},{signature,[{algorithm,ed25519},{key_id,k1},{value,<<0,0,0,0>>}]}], envelope:verify_signature(BadEnv, AS) =:= {error,bad_signature}\") :name)")
+
+;; unknown key_id -> no_active_key
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${PRELUDE} OtherAS = [{public_keys, [[{id,k_other},{created,50},{value,KM}]]}], envelope:verify_signature(Env, OtherAS) =:= {error,no_active_key}\") :name)")
+
+;; key superseded BEFORE published -> no_active_key
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${PRELUDE} SupAS = [{public_keys, [[{id,k1},{created,50},{superseded_at,80},{value,KM}]]}], envelope:verify_signature(Env, SupAS) =:= {error,no_active_key}\") :name)")
+
+;; key superseded AFTER published -> ok (historical valid)
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${PRELUDE} SupAS2 = [{public_keys, [[{id,k1},{created,50},{superseded_at,200},{value,KM}]]}], envelope:verify_signature(Env, SupAS2) =:= ok\") :name)")
+
+;; key not yet created at published -> no_active_key
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${PRELUDE} FutAS = [{public_keys, [[{id,k1},{created,150},{value,KM}]]}], envelope:verify_signature(Env, FutAS) =:= {error,no_active_key}\") :name)")
+
+;; missing signature field -> no_signature
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${PRELUDE} envelope:verify_signature(U, AS) =:= {error,no_signature}\") :name)")
+
+;; actor state with no public_keys field -> no_keys
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${PRELUDE} envelope:verify_signature(Env, []) =:= {error,no_keys}\") :name)")
+
+;; second key in list matches when first doesn't (lookup walks list)
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${PRELUDE} TwoKeys = [{public_keys, [[{id,k_other},{created,50},{value,<<9,9,9>>}], [{id,k1},{created,50},{value,KM}]]}], envelope:verify_signature(Env, TwoKeys) =:= ok\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                "envelope"
+check 10  "valid sig active key"            "true"
+check 11  "tampered envelope"               "true"
+check 12  "wrong sig value"                 "true"
+check 13  "unknown key_id"                  "true"
+check 14  "key superseded before published" "true"
+check 15  "key superseded after published"  "true"
+check 16  "key not yet created"             "true"
+check 17  "missing signature field"         "true"
+check 18  "actor state no keys"             "true"
+check 19  "match second key in list"        "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/envelope_sig.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/follow_lifecycle.sh

@@ -0,0 +1,137 @@
+#!/usr/bin/env bash
+# next/tests/follow_lifecycle.sh — m2 Step 6b test.
+#
+# Ties Step 5 (POST /actors/<id>/inbox real ingestion) to Step 6a
+# (follower_graph projection) via Cfg :inbox_projections. The
+# inbox handler casts every successfully-ingested activity into
+# each named projection — the follower_graph state mutates as
+# Follow / Accept / Reject / Undo activities land.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Alice is on this kernel (target). Bob is the peer (signs activities
+# with BobKS). PeerAS = Bob's actor-state (Bob's public_keys). The
+# :inbox_projections wires inbound to the followers projection so
+# follower_graph state advances on every successful ingestion.
+SETUP='AK = <<1,2,3,4>>, AKS = [{key_id,k1},{algorithm,ed25519},{value,AK}], AAS = [{public_keys,[[{id,k1},{created,0},{value,AK}]]}], BK = <<5,6,7,8>>, BKS = [{key_id,k1},{algorithm,ed25519},{value,BK}], BAS = [{public_keys,[[{id,k1},{created,0},{value,BK}]]}], FollowReq = [{actor, bob}, {type, follow}, {object, alice}, {published, 1}], FollowEnv = outbox:construct(follow, bob, 1, alice), SignedFollow = outbox:sign(FollowEnv, BKS), Body = term_codec:encode(SignedFollow), nx_kernel:start_link(alice, AKS, AAS), projection:start_link(followers, follower_graph:new(), follower_graph:fold_fn()), Cfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}], InboxPath = <<47,97,99,116,111,114,115,47,97,108,105,99,101,47,105,110,98,111,120>>,'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(er-load-gen-server!)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 4)
+(eval "(get (erlang-load-module (file-read \"next/kernel/log.erl\")) :name)")
+(epoch 5)
+(eval "(get (erlang-load-module (file-read \"next/kernel/pipeline.erl\")) :name)")
+(epoch 6)
+(eval "(get (erlang-load-module (file-read \"next/kernel/outbox.erl\")) :name)")
+(epoch 7)
+(eval "(get (erlang-load-module (file-read \"next/kernel/projection.erl\")) :name)")
+(epoch 8)
+(eval "(get (erlang-load-module (file-read \"next/kernel/nx_kernel.erl\")) :name)")
+(epoch 9)
+(eval "(get (erlang-load-module (file-read \"next/kernel/term_codec.erl\")) :name)")
+(epoch 10)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+(epoch 11)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; Follow peer -> 202 from inbox handler
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], case http_server:route(Req, Cfg) of [{status, 202}, _, _] -> true; _ -> false end\") :name)")
+
+;; After Follow: follower_graph state shows alice with pending_inbound = [bob]
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {object, alice}, {body, Body}], http_server:route(Req, Cfg), follower_graph:pending_inbound(alice, projection:query(followers)) =:= [bob]\") :name)")
+
+;; And bob has pending_outbound = [alice]
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), follower_graph:pending_outbound(bob, projection:query(followers)) =:= [alice]\") :name)")
+
+;; Inbox tip advanced even without auto-Accept (separate concern)
+(epoch 23)
+(eval "(erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), nx_kernel:inbox_tip_for(alice)\")")
+
+;; No :inbox_projections in Cfg: projection state stays empty
+(epoch 24)
+(eval "(get (erlang-eval-ast \"${SETUP} BareCfg = [{peer_as, [{bob, BAS}]}, {kernel, nx_kernel}], Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, BareCfg), follower_graph:pending_inbound(alice, projection:query(followers)) =:= []\") :name)")
+
+;; Follow + Accept end-to-end: bob -> alice (Follow), alice -> bob (Accept via outbox).
+;; v2 only has the inbox side wired; the Accept is built locally in the test and
+;; folded through the same projection to demonstrate that the projection state
+;; converges. Auto-Accept publish lands in 6c.
+(epoch 25)
+(eval "(get (erlang-eval-ast \"${SETUP} Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, Cfg), AcceptAct = [{actor, alice}, {type, accept}, {object, [{actor, bob}, {type, follow}, {object, alice}]}], projection:async_fold(followers, AcceptAct), S = projection:query(followers), follower_graph:followers(alice, S) =:= [bob] andalso follower_graph:following(bob, S) =:= [alice]\") :name)")
+
+;; Inbox handler with bad sig fails BEFORE projection broadcast
+(epoch 26)
+(eval "(get (erlang-eval-ast \"AK = <<1,2,3,4>>, AKS = [{key_id,k1},{algorithm,ed25519},{value,AK}], AAS = [{public_keys,[[{id,k1},{created,0},{value,AK}]]}], EvilK = <<9,9,9,9>>, EvilAS = [{public_keys,[[{id,k1},{created,0},{value,EvilK}]]}], BK = <<5,6,7,8>>, BKS = [{key_id,k1},{algorithm,ed25519},{value,BK}], FollowEnv = outbox:construct(follow, bob, 1, alice), SignedFollow = outbox:sign(FollowEnv, BKS), Body = term_codec:encode(SignedFollow), nx_kernel:start_link(alice, AKS, AAS), projection:start_link(followers, follower_graph:new(), follower_graph:fold_fn()), EvilCfg = [{peer_as, [{bob, EvilAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}], InboxPath = <<47,97,99,116,111,114,115,47,97,108,105,99,101,47,105,110,98,111,120>>, Req = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], http_server:route(Req, EvilCfg), follower_graph:actors(projection:query(followers)) =:= []\") :name)")
+
+;; Multiple distinct peer Follows accumulate
+(epoch 27)
+(eval "(get (erlang-eval-ast \"${SETUP} CK = <<9,9,9,9>>, CKS = [{key_id,k1},{algorithm,ed25519},{value,CK}], CAS = [{public_keys,[[{id,k1},{created,0},{value,CK}]]}], MultiCfg = [{peer_as, [{bob, BAS}, {carol, CAS}]}, {kernel, nx_kernel}, {inbox_projections, [followers]}], CarolEnv = outbox:construct(follow, carol, 1, alice), CarolSigned = outbox:sign(CarolEnv, CKS), CarolBody = term_codec:encode(CarolSigned), Req1 = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, Body}], Req2 = [{method, <<80,79,83,84>>}, {path, InboxPath}, {headers, []}, {body, CarolBody}], http_server:route(Req1, MultiCfg), http_server:route(Req2, MultiCfg), follower_graph:pending_inbound(alice, projection:query(followers)) =:= [bob, carol]\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 900 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check 11  "http_server module loaded"        "http_server"
+check 20  "Follow ingestion -> 202"          "true"
+check 21  "alice.pending_inbound = [bob]"    "true"
+check 22  "bob.pending_outbound = [alice]"   "true"
+check 23  "inbox tip advances to 1"          "1"
+check 24  "no inbox_projections -> no fold"  "true"
+check 25  "Follow + Accept projection state" "true"
+check 26  "bad sig doesn't pollute projection" "true"
+check 27  "two distinct peer Follows accumulate" "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/follow_lifecycle.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/follower_graph.sh

@@ -0,0 +1,159 @@
+#!/usr/bin/env bash
+# next/tests/follower_graph.sh — m2 Step 6a test.
+#
+# Pure projection fold over Follow / Accept / Reject / Undo
+# activities per design §13.2. State tracks per-actor
+# {following, followers, pending_outbound, pending_inbound} lists.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# F(A→B) is the embedded Follow object Accept / Reject / Undo wrap.
+SETUP='F = [{type, follow}, {actor, alice}, {object, bob}], Follow = [{actor, alice}, {type, follow}, {object, bob}], Accept = [{actor, bob}, {type, accept}, {object, F}], Reject = [{actor, bob}, {type, reject}, {object, F}], Undo = [{actor, alice}, {type, undo}, {object, F}],'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/envelope.erl\")) :name)")
+(epoch 3)
+(eval "(get (erlang-load-module (file-read \"next/kernel/follower_graph.erl\")) :name)")
+
+;; new/0 -> []
+(epoch 10)
+(eval "(get (erlang-eval-ast \"follower_graph:new() =:= []\") :name)")
+
+;; Follow alice->bob: alice has pending_outbound = [bob]; bob pending_inbound = [alice]
+(epoch 11)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), follower_graph:pending_outbound(alice, S) =:= [bob] andalso follower_graph:pending_inbound(bob, S) =:= [alice]\") :name)")
+
+;; After Follow alone, neither party shows the other as following/follower
+(epoch 12)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), follower_graph:following(alice, S) =:= [] andalso follower_graph:followers(bob, S) =:= []\") :name)")
+
+;; Accept: alice moves into bob's followers; bob moves into alice's following
+(epoch 13)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Accept, S), follower_graph:followers(bob, S1) =:= [alice] andalso follower_graph:following(alice, S1) =:= [bob]\") :name)")
+
+;; Accept: both pending lists cleared on each side
+(epoch 14)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Accept, S), follower_graph:pending_outbound(alice, S1) =:= [] andalso follower_graph:pending_inbound(bob, S1) =:= []\") :name)")
+
+;; Reject: pending lists clear without populating following/followers
+(epoch 15)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Reject, S), follower_graph:pending_outbound(alice, S1) =:= [] andalso follower_graph:pending_inbound(bob, S1) =:= [] andalso follower_graph:following(alice, S1) =:= [] andalso follower_graph:followers(bob, S1) =:= []\") :name)")
+
+;; Undo by alice after accept: drops both following and followers
+(epoch 16)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Accept, S), S2 = follower_graph:fold(Undo, S1), follower_graph:following(alice, S2) =:= [] andalso follower_graph:followers(bob, S2) =:= []\") :name)")
+
+;; Undo before accept: pending lists clear
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Undo, S), follower_graph:pending_outbound(alice, S1) =:= [] andalso follower_graph:pending_inbound(bob, S1) =:= []\") :name)")
+
+;; Self-follow ignored (alice follows alice no-ops)
+(epoch 18)
+(eval "(get (erlang-eval-ast \"SelfFollow = [{actor, alice}, {type, follow}, {object, alice}], S = follower_graph:fold(SelfFollow, follower_graph:new()), follower_graph:new() =:= S\") :name)")
+
+;; Two distinct follows: alice->bob, carol->bob produce two pending_inbound entries on bob
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${SETUP} F2 = [{actor, carol}, {type, follow}, {object, bob}], S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(F2, S), follower_graph:pending_inbound(bob, S1) =:= [alice, carol]\") :name)")
+
+;; Duplicate Follow is idempotent (no double-add)
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), S1 = follower_graph:fold(Follow, S), follower_graph:pending_outbound(alice, S1) =:= [bob]\") :name)")
+
+;; Predicates: is_following / has_follower / pendings after accept
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Accept, follower_graph:fold(Follow, follower_graph:new())), {follower_graph:is_following(alice, bob, S), follower_graph:has_follower(bob, alice, S), follower_graph:is_pending_outbound(alice, bob, S), follower_graph:is_pending_inbound(bob, alice, S)} =:= {true, true, false, false}\") :name)")
+
+;; actors/1 lists every actor seen (alice + bob after one Follow,
+;; in insertion order: alice's bucket added first, then bob's)
+(epoch 22)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Follow, follower_graph:new()), follower_graph:actors(S) =:= [alice, bob]\") :name)")
+
+;; fold_fn/0 is a 2-arity Erlang fun (plugs into projection:start_link)
+(epoch 23)
+(eval "(get (erlang-eval-ast \"is_function(follower_graph:fold_fn(), 2)\") :name)")
+
+;; Activity sans :type passes through
+(epoch 24)
+(eval "(get (erlang-eval-ast \"Garbage = [{actor, alice}], follower_graph:fold(Garbage, follower_graph:new()) =:= []\") :name)")
+
+;; Accept whose embedded :object isn't a Follow passes through
+(epoch 25)
+(eval "(get (erlang-eval-ast \"BadAccept = [{actor, bob}, {type, accept}, {object, [{type, note}, {actor, alice}, {object, bob}]}], follower_graph:fold(BadAccept, follower_graph:new()) =:= []\") :name)")
+
+;; Undo by the wrong actor (carol trying to undo F where A=alice) is a no-op
+(epoch 26)
+(eval "(get (erlang-eval-ast \"${SETUP} S = follower_graph:fold(Accept, follower_graph:fold(Follow, follower_graph:new())), BadUndo = [{actor, carol}, {type, undo}, {object, F}], S1 = follower_graph:fold(BadUndo, S), follower_graph:following(alice, S1) =:= [bob]\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 240 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  3  "follower_graph module loaded"     "follower_graph"
+check 10  "new/0 -> []"                      "true"
+check 11  "Follow sets pendings each side"   "true"
+check 12  "Follow alone: no following/follower" "true"
+check 13  "Accept promotes to following/followers" "true"
+check 14  "Accept clears pendings"           "true"
+check 15  "Reject clears without promote"    "true"
+check 16  "Undo after accept drops rel"      "true"
+check 17  "Undo before accept clears pending" "true"
+check 18  "self-follow is a no-op"           "true"
+check 19  "two follows -> two pending_inbound" "true"
+check 20  "duplicate Follow idempotent"      "true"
+check 21  "predicates after accept"          "true"
+check 22  "actors/1 lists every seen"        "true"
+check 23  "fold_fn/0 is fun/2"               "true"
+check 24  "untyped activity passes through"  "true"
+check 25  "Accept of non-Follow passes through" "true"
+check 26  "Undo by wrong actor no-op"        "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/follower_graph.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/genesis_parse.sh

@@ -0,0 +1,239 @@
+#!/usr/bin/env bash
+# next/tests/genesis_parse.sh — Step 4a acceptance test.
+#
+# Confirms the seed genesis SX files parse cleanly and have the
+# expected top-level head form. The bundler (Step 4c+) consumes
+# these forms directly as data. 50 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 10)
+(eval "(first (parse (file-read \"next/genesis/manifest.sx\")))")
+(epoch 11)
+(eval "(first (parse (file-read \"next/genesis/activity-types/create.sx\")))")
+(epoch 12)
+(eval "(first (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :activity-types))")
+(epoch 13)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/activity-types/create.sx\")))) :name)")
+(epoch 14)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :version)")
+(epoch 15)
+(eval "(first (parse (file-read \"next/genesis/activity-types/update.sx\")))")
+(epoch 16)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/activity-types/update.sx\")))) :name)")
+(epoch 17)
+(eval "(first (parse (file-read \"next/genesis/activity-types/delete.sx\")))")
+(epoch 18)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/activity-types/delete.sx\")))) :name)")
+(epoch 27)
+(eval "(first (parse (file-read \"next/genesis/activity-types/announce.sx\")))")
+(epoch 28)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/activity-types/announce.sx\")))) :name)")
+(epoch 29)
+(eval "(first (parse (file-read \"next/genesis/activity-types/endorse.sx\")))")
+(epoch 200)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/activity-types/endorse.sx\")))) :name)")
+(epoch 19)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :activity-types))")
+(epoch 30)
+(eval "(first (parse (file-read \"next/genesis/object-types/sx-artifact.sx\")))")
+(epoch 31)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/sx-artifact.sx\")))) :name)")
+(epoch 32)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/note.sx\")))) :name)")
+(epoch 33)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/tombstone.sx\")))) :name)")
+(epoch 34)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-activity.sx\")))) :name)")
+(epoch 35)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-object.sx\")))) :name)")
+(epoch 36)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-projection.sx\")))) :name)")
+(epoch 37)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-validator.sx\")))) :name)")
+(epoch 38)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-codec.sx\")))) :name)")
+(epoch 39)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/define-sig-suite.sx\")))) :name)")
+(epoch 40)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/snapshot.sx\")))) :name)")
+(epoch 42)
+(eval "(first (parse (file-read \"next/genesis/object-types/person.sx\")))")
+(epoch 43)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/person.sx\")))) :name)")
+(epoch 44)
+(eval "(first (parse (file-read \"next/genesis/object-types/service.sx\")))")
+(epoch 45)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/service.sx\")))) :name)")
+(epoch 46)
+(eval "(first (parse (file-read \"next/genesis/object-types/group.sx\")))")
+(epoch 47)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/object-types/group.sx\")))) :name)")
+(epoch 48)
+(eval "(some (fn (p) (= p \"object-types/person.sx\")) (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :object-types))")
+(epoch 41)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :object-types))")
+(epoch 50)
+(eval "(first (parse (file-read \"next/genesis/projections/activity-log.sx\")))")
+(epoch 51)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/activity-log.sx\")))) :name)")
+(epoch 52)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/by-type.sx\")))) :name)")
+(epoch 53)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/by-actor.sx\")))) :name)")
+(epoch 54)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/by-object.sx\")))) :name)")
+(epoch 55)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/actor-state.sx\")))) :name)")
+(epoch 56)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/define-registry.sx\")))) :name)")
+(epoch 57)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/projections/audience-graph.sx\")))) :name)")
+(epoch 58)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :projections))")
+(epoch 60)
+(eval "(first (parse (file-read \"next/genesis/validators/envelope-shape.sx\")))")
+(epoch 61)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/validators/envelope-shape.sx\")))) :name)")
+(epoch 62)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/validators/signature.sx\")))) :name)")
+(epoch 63)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/validators/type-schema.sx\")))) :name)")
+(epoch 64)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :validators))")
+(epoch 70)
+(eval "(first (parse (file-read \"next/genesis/codecs/dag-cbor.sx\")))")
+(epoch 71)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/codecs/dag-cbor.sx\")))) :name)")
+(epoch 72)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/codecs/raw.sx\")))) :name)")
+(epoch 73)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/codecs/dag-json.sx\")))) :name)")
+(epoch 74)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :codecs))")
+(epoch 80)
+(eval "(first (parse (file-read \"next/genesis/sig-suites/rsa-sha256-2018.sx\")))")
+(epoch 81)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/sig-suites/rsa-sha256-2018.sx\")))) :name)")
+(epoch 82)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/sig-suites/ed25519-2020.sx\")))) :name)")
+(epoch 83)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :sig-suites))")
+(epoch 90)
+(eval "(first (parse (file-read \"next/genesis/audience/public.sx\")))")
+(epoch 91)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/audience/public.sx\")))) :name)")
+(epoch 92)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/audience/followers.sx\")))) :name)")
+(epoch 93)
+(eval "(get (apply dict (rest (parse (file-read \"next/genesis/audience/direct.sx\")))) :name)")
+(epoch 94)
+(eval "(len (get (apply dict (rest (parse (file-read \"next/genesis/manifest.sx\")))) :audience))")
+EPOCHS
+
+OUTPUT=$(timeout 30 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check 10 "manifest.sx head form"        "GenesisManifest"
+check 11 "create.sx head form"          "DefineActivity"
+check 12 "manifest lists create.sx"     "activity-types/create.sx"
+check 13 "create.sx name is Create"     "Create"
+check 14 "manifest version present"     "0.0.1"
+check 15 "update.sx head form"          "DefineActivity"
+check 16 "update.sx name is Update"     "Update"
+check 17 "delete.sx head form"          "DefineActivity"
+check 18 "delete.sx name is Delete"     "Delete"
+check 27 "announce.sx head form"        "DefineActivity"
+check 28 "announce.sx name is Announce" "Announce"
+check 29 "endorse.sx head form"         "DefineActivity"
+check 200 "endorse.sx name is Endorse"  "Endorse"
+check 19 "manifest has 5 activity-types" "5"
+check 30 "sx-artifact.sx head form"     "DefineObject"
+check 31 "sx-artifact.sx name"          "SXArtifact"
+check 32 "note.sx name"                 "Note"
+check 33 "tombstone.sx name"            "Tombstone"
+check 34 "define-activity.sx name"      "DefineActivity"
+check 35 "define-object.sx name"        "DefineObject"
+check 36 "define-projection.sx name"    "DefineProjection"
+check 37 "define-validator.sx name"     "DefineValidator"
+check 38 "define-codec.sx name"         "DefineCodec"
+check 39 "define-sig-suite.sx name"     "DefineSigSuite"
+check 40 "snapshot.sx name"             "Snapshot"
+check 42 "person.sx head form"          "DefineObject"
+check 43 "person.sx name"               "Person"
+check 44 "service.sx head form"         "DefineObject"
+check 45 "service.sx name"              "Service"
+check 46 "group.sx head form"           "DefineObject"
+check 47 "group.sx name"                "Group"
+check 48 "manifest lists person.sx"     "true"
+check 41 "manifest has 13 object-types" "13"
+check 50 "activity-log.sx head form"    "DefineProjection"
+check 51 "activity-log.sx name"         "activity-log"
+check 52 "by-type.sx name"              "by-type"
+check 53 "by-actor.sx name"             "by-actor"
+check 54 "by-object.sx name"            "by-object"
+check 55 "actor-state.sx name"          "actor-state"
+check 56 "define-registry.sx name"      "define-registry"
+check 57 "audience-graph.sx name"       "audience-graph"
+check 58 "manifest has 7 projections"   "7"
+check 60 "envelope-shape.sx head form"  "DefineValidator"
+check 61 "envelope-shape.sx name"       "envelope-shape"
+check 62 "signature.sx name"            "signature"
+check 63 "type-schema.sx name"          "type-schema"
+check 64 "manifest has 3 validators"    "3"
+check 70 "dag-cbor.sx head form"        "DefineCodec"
+check 71 "dag-cbor.sx name"             "dag-cbor"
+check 72 "raw.sx name"                  "raw"
+check 73 "dag-json.sx name"             "dag-json"
+check 74 "manifest has 3 codecs"        "3"
+check 80 "rsa-sha256-2018.sx head form" "DefineSigSuite"
+check 81 "rsa-sha256-2018.sx name"      "rsa-sha256-2018"
+check 82 "ed25519-2020.sx name"         "ed25519-2020"
+check 83 "manifest has 2 sig-suites"    "2"
+check 90 "public.sx head form"          "DefineAudience"
+check 91 "public.sx name"               "Public"
+check 92 "followers.sx name"            "Followers"
+check 93 "direct.sx name"               "Direct"
+check 94 "manifest has 3 audience"      "3"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/genesis_parse.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/http_accept.sh

@@ -0,0 +1,128 @@
+#!/usr/bin/env bash
+# next/tests/http_accept.sh — Step 8d-accept acceptance test.
+#
+# Exercises accept_format/1 + accept_format_from/1. 12 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; activity_json
+(epoch 10)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<97,112,112,108,105,99,97,116,105,111,110,47,97,99,116,105,118,105,116,121,43,106,115,111,110>>)\") :name)")
+
+;; json
+(epoch 11)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<97,112,112,108,105,99,97,116,105,111,110,47,106,115,111,110>>)\") :name)")
+
+;; sx
+(epoch 12)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<97,112,112,108,105,99,97,116,105,111,110,47,115,120>>)\") :name)")
+
+;; cbor
+(epoch 13)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<97,112,112,108,105,99,97,116,105,111,110,47,99,98,111,114>>)\") :name)")
+
+;; text/plain -> text
+(epoch 14)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<116,101,120,116,47,112,108,97,105,110>>)\") :name)")
+
+;; nil -> text
+(epoch 15)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(nil)\") :name)")
+
+;; empty binary -> text
+(epoch 16)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<>>)\") :name)")
+
+;; activity_json wins over json when both present at the start
+;; "application/activity+json, application/json"
+(epoch 17)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(<<97,112,112,108,105,99,97,116,105,111,110,47,97,99,116,105,118,105,116,121,43,106,115,111,110,44,32,97,112,112,108,105,99,97,116,105,111,110,47,106,115,111,110>>)\") :name)")
+
+;; accept_format_from with no header field -> text
+(epoch 18)
+(eval "(get (erlang-eval-ast \"http_server:accept_format_from([])\") :name)")
+
+;; accept_format_from with Accept header
+(epoch 19)
+(eval "(get (erlang-eval-ast \"AK = <<97,99,99,101,112,116>>, AV = <<97,112,112,108,105,99,97,116,105,111,110,47,115,120>>, http_server:accept_format_from([{headers, [{AK, AV}]}])\") :name)")
+
+;; accept_format_from with headers but no Accept -> text
+(epoch 20)
+(eval "(get (erlang-eval-ast \"OK = <<102,111,111>>, http_server:accept_format_from([{headers, [{OK, <<98,97,114>>}]}])\") :name)")
+
+;; accept_format on a non-binary returns text
+(epoch 21)
+(eval "(get (erlang-eval-ast \"http_server:accept_format(some_atom)\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 360 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                  "http_server"
+check 10  "activity+json -> activity_json"    "activity_json"
+check 11  "json -> json"                      "json"
+check 12  "sx -> sx"                          "sx"
+check 13  "cbor -> cbor"                      "cbor"
+check 14  "text/plain -> text"                "text"
+check 15  "nil -> text"                       "text"
+check 16  "empty binary -> text"              "text"
+check 17  "activity+json wins over json"      "activity_json"
+check 18  "no headers -> text"                "text"
+check 19  "Accept: application/sx -> sx"      "sx"
+check 20  "no Accept header -> text"          "text"
+check 21  "non-binary input -> text"          "text"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/http_accept.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/http_actors.sh

@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+# next/tests/http_actors.sh — Step 8c-actors acceptance test.
+#
+# Exercises match_prefix/2 + GET /actors/{id} route. The id is
+# carried back in the response body so callers can confirm the
+# right segment was extracted. 12 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; match_prefix on a clean match returns the rest
+(epoch 10)
+(eval "(get (erlang-eval-ast \"http_server:match_prefix(<<97,98>>, <<97,98,99,100>>) =:= {ok, <<99,100>>}\") :name)")
+
+;; Empty prefix matches everything
+(epoch 11)
+(eval "(get (erlang-eval-ast \"http_server:match_prefix(<<>>, <<97,98,99>>) =:= {ok, <<97,98,99>>}\") :name)")
+
+;; No common bytes -> nomatch
+(epoch 12)
+(eval "(get (erlang-eval-ast \"http_server:match_prefix(<<97,98>>, <<120,121>>) =:= nomatch\") :name)")
+
+;; Prefix longer than path -> nomatch
+(epoch 13)
+(eval "(get (erlang-eval-ast \"http_server:match_prefix(<<97,98,99,100>>, <<97,98>>) =:= nomatch\") :name)")
+
+;; Exact match yields empty rest
+(epoch 14)
+(eval "(get (erlang-eval-ast \"http_server:match_prefix(<<97,98>>, <<97,98>>) =:= {ok, <<>>}\") :name)")
+
+;; actors_prefix is "/actors/" — 8 bytes
+(epoch 15)
+(eval "(erlang-eval-ast \"byte_size(http_server:actors_prefix())\")")
+
+;; GET /actors/alice -> 200
+(epoch 16)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<71,69,84>>}, {path, <<47,97,99,116,111,114,115,47,97,108,105,99,101>>}], case http_server:route(Req) of [{status, 200} | _] -> ok; _ -> bad end\") :name)")
+
+;; The id appears in the body
+(epoch 17)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<71,69,84>>}, {path, <<47,97,99,116,111,114,115,47,97,108,105,99,101>>}], R = http_server:route(Req), case R of [_, _, {body, B}] -> http_server:match_prefix(<<97,99,116,111,114,58,32>>, B) =/= nomatch; _ -> false end\") :name)")
+
+;; GET /actors/ (empty id) -> 404
+(epoch 18)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<71,69,84>>}, {path, <<47,97,99,116,111,114,115,47>>}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+
+;; POST /actors/alice -> 404 (only GET)
+(epoch 19)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<80,79,83,84>>}, {path, <<47,97,99,116,111,114,115,47,97,108,105,99,101>>}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+
+;; GET /unrelated still 404
+(epoch 20)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<71,69,84>>}, {path, <<47,102,111,111>>}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+
+;; Existing routes (GET /, capabilities) still work
+(epoch 21)
+(eval "(get (erlang-eval-ast \"Req1 = [{method, <<71,69,84>>}, {path, <<47>>}], Req2 = [{method, <<71,69,84>>}, {path, http_server:capabilities_path()}], R1 = case http_server:route(Req1) of [{status, 200} | _] -> ok; _ -> bad end, R2 = case http_server:route(Req2) of [{status, 200} | _] -> ok; _ -> bad end, {R1, R2} =:= {ok, ok}\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 360 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                  "http_server"
+check 10  "match_prefix clean match"          "true"
+check 11  "empty prefix matches all"          "true"
+check 12  "no common bytes -> nomatch"        "true"
+check 13  "prefix > path -> nomatch"          "true"
+check 14  "exact match -> empty rest"         "true"
+check 15  "actors_prefix size = 8"            "8"
+check 16  "GET /actors/alice -> 200"          "ok"
+check 17  "body carries 'actor: ' prefix"     "true"
+check 18  "GET /actors/ (empty id) -> 404"    "ok"
+check 19  "POST /actors/alice -> 404"         "ok"
+check 20  "GET /unrelated still 404"          "ok"
+check 21  "existing routes intact"            "true"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/http_actors.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

next/tests/http_artifacts.sh

@@ -0,0 +1,108 @@
+#!/usr/bin/env bash
+# next/tests/http_artifacts.sh — Step 8c-art acceptance test.
+#
+# Exercises GET /artifacts/{cid} via the shared match_prefix
+# machinery. Mirrors the actors-route test shape. 9 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+cat > "$TMPFILE" <<'EPOCHS'
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; artifacts_prefix is "/artifacts/" — 11 bytes
+(epoch 10)
+(eval "(erlang-eval-ast \"byte_size(http_server:artifacts_prefix())\")")
+
+;; GET /artifacts/<cid> -> 200
+(epoch 11)
+(eval "(get (erlang-eval-ast \"Cid = <<98,97,102,107,114,101,49>>, Req = [{method, <<71,69,84>>}, {path, <<(http_server:artifacts_prefix())/binary, Cid/binary>>}], case http_server:route(Req) of [{status, 200} | _] -> ok; _ -> bad end\") :name)")
+
+;; The cid is echoed in the body (carries 'artifact: ' prefix)
+(epoch 12)
+(eval "(get (erlang-eval-ast \"Cid = <<98,97,102,107,114,101,49>>, Req = [{method, <<71,69,84>>}, {path, <<(http_server:artifacts_prefix())/binary, Cid/binary>>}], R = http_server:route(Req), case R of [_, _, {body, B}] -> http_server:match_prefix(<<97,114,116,105,102,97,99,116,58,32>>, B) =/= nomatch; _ -> false end\") :name)")
+
+;; GET /artifacts/ (empty cid) -> 404
+(epoch 13)
+(eval "(get (erlang-eval-ast \"Req = [{method, <<71,69,84>>}, {path, http_server:artifacts_prefix()}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+
+;; POST /artifacts/<cid> -> 404 (only GET)
+(epoch 14)
+(eval "(get (erlang-eval-ast \"Cid = <<98,97,102>>, Req = [{method, <<80,79,83,84>>}, {path, <<(http_server:artifacts_prefix())/binary, Cid/binary>>}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+
+;; Actor and artifact routes don't collide
+(epoch 15)
+(eval "(get (erlang-eval-ast \"R1 = http_server:route([{method, <<71,69,84>>}, {path, <<47,97,99,116,111,114,115,47,97>>}]), R2 = http_server:route([{method, <<71,69,84>>}, {path, <<(http_server:artifacts_prefix())/binary, 98>>}]), case {R1, R2} of {[{status, 200} | _], [{status, 200} | _]} -> ok; _ -> bad end\") :name)")
+
+;; Existing routes (GET /, capabilities) still work
+(epoch 16)
+(eval "(get (erlang-eval-ast \"R1 = case http_server:route([{method, <<71,69,84>>}, {path, <<47>>}]) of [{status, 200} | _] -> ok; _ -> bad end, R2 = case http_server:route([{method, <<71,69,84>>}, {path, http_server:capabilities_path()}]) of [{status, 200} | _] -> ok; _ -> bad end, {R1, R2} =:= {ok, ok}\") :name)")
+
+;; artifacts_prefix starts with '/'
+(epoch 17)
+(eval "(get (erlang-eval-ast \"case http_server:artifacts_prefix() of <<47, _/binary>> -> ok; _ -> bad end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 360 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                  "http_server"
+check 10  "artifacts_prefix size = 11"        "11"
+check 11  "GET /artifacts/<cid> -> 200"       "ok"
+check 12  "body carries 'artifact: '"         "true"
+check 13  "GET /artifacts/ (empty) -> 404"    "ok"
+check 14  "POST /artifacts/<cid> -> 404"      "ok"
+check 15  "actors + artifacts no collision"   "ok"
+check 16  "static routes still 200"           "true"
+check 17  "artifacts_prefix leading /"        "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/http_artifacts.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]