diff --git a/hosts/ocaml/bin/sx_server.ml b/hosts/ocaml/bin/sx_server.ml
index 9cab15d3..ec706aa3 100644
--- a/hosts/ocaml/bin/sx_server.ml
+++ b/hosts/ocaml/bin/sx_server.ml
@@ -18,123 +18,6 @@
 
 open Sx_types
 
-(* ====================================================================== *)
-(* Font measurement via otfm — reads OpenType/TrueType font tables         *)
-(* ====================================================================== *)
-
-(* Font cache: font-family → (units_per_em, glyph_id_map, advance_width_map) *)
-let _font_cache : (string, (int * (int, int) Hashtbl.t * (int, int) Hashtbl.t)) Hashtbl.t = Hashtbl.create 4
-
-(* Map font-family names to file paths *)
-let _font_base = ref "shared/static/fonts"
-
-let font_path_for family =
-  let base = !_font_base in
-  let try_paths paths =
-    List.find_opt Sys.file_exists paths in
-  match String.lowercase_ascii family with
-  | "serif" | "times" | "times new roman" ->
-    try_paths [base ^ "/DejaVuSerif.ttf";
-               "/usr/share/fonts/truetype/dejavu/DejaVuSerif.ttf"]
-  | "sans-serif" | "sans" | "arial" | "helvetica" ->
-    try_paths [base ^ "/DejaVuSans.ttf";
-               "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf"]
-  | "monospace" | "mono" | "courier" ->
-    try_paths [base ^ "/DejaVuSansMono-Bold.ttf";
-               "/usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf"]
-  | path when Sys.file_exists path -> Some path
-  | _ -> try_paths [base ^ "/DejaVuSerif.ttf";
-                     "/usr/share/fonts/truetype/dejavu/DejaVuSerif.ttf"]
-
-(* Load a font file and extract cmap + hmtx tables *)
-let load_font family =
-  match Hashtbl.find_opt _font_cache family with
-  | Some cached -> Some cached
-  | None ->
-    match font_path_for family with
-    | None -> None
-    | Some path ->
-      try
-        let ic = open_in_bin path in
-        let n = in_channel_length ic in
-        let buf = Bytes.create n in
-        really_input ic buf 0 n;
-        close_in ic;
-        let s = Bytes.to_string buf in
-        let d = Otfm.decoder (`String s) in
-        (* Get units_per_em from head table *)
-        let upm = match Otfm.head d with
-          | Error _ -> 2048
-          | Ok h -> h.Otfm.head_units_per_em in
-        (* Build char→glyph_id map from cmap.
-           cmap folds: (acc -> map_kind -> (u0,u1) -> glyph_id -> acc) *)
-        let cmap_tbl = Hashtbl.create 256 in
-        let _ = Otfm.cmap d (fun acc kind (u0, u1) gid ->
-          (match kind with
-           | `Glyph ->
-             (* Single mapping: u0 -> gid (u0 = u1) *)
-             Hashtbl.replace cmap_tbl u0 gid
-           | `Glyph_range ->
-             (* Range: u0..u1 -> gid..(gid + u1 - u0) *)
-             for i = 0 to u1 - u0 do
-               Hashtbl.replace cmap_tbl (u0 + i) (gid + i)
-             done);
-          acc) () in
-        (* Build glyph_id→advance_width map from hmtx.
-           hmtx folds: (acc -> glyph_id -> adv_width -> lsb -> acc) *)
-        let hmtx_tbl = Hashtbl.create 256 in
-        let _ = Otfm.hmtx d (fun acc gid adv _lsb ->
-          Hashtbl.replace hmtx_tbl gid adv; acc) () in
-        let result = (upm, cmap_tbl, hmtx_tbl) in
-        Printf.eprintf "[font] loaded %s: %d glyphs, %d metrics, upm=%d\n%!"
-          (Filename.basename path) (Hashtbl.length cmap_tbl) (Hashtbl.length hmtx_tbl) upm;
-        Hashtbl.replace _font_cache family result;
-        Some result
-      with e ->
-        Printf.eprintf "[font] error loading %s: %s\n%!" path (Printexc.to_string e);
-        None
-
-(* Measure text width using font tables *)
-let measure_text_otfm family size text =
-  match load_font family with
-  | None ->
-    (* Fallback to monospace approximation *)
-    let w = size *. 0.6 *. (float_of_int (String.length text)) in
-    (w, size, size *. 0.8, size *. 0.2)
-  | Some (upm, cmap_tbl, hmtx_tbl) ->
-    let scale = size /. (float_of_int upm) in
-    let width = ref 0.0 in
-    (* Iterate over UTF-8 codepoints *)
-    let i = ref 0 in
-    let len = String.length text in
-    while !i < len do
-      let byte = Char.code text.[!i] in
-      let cp, advance =
-        if byte < 0x80 then (byte, 1)
-        else if byte < 0xC0 then (byte, 1)  (* continuation — skip *)
-        else if byte < 0xE0 then
-          ((byte land 0x1F) lsl 6 lor (Char.code text.[min (!i+1) (len-1)] land 0x3F), 2)
-        else if byte < 0xF0 then
-          ((byte land 0x0F) lsl 12
-           lor (Char.code text.[min (!i+1) (len-1)] land 0x3F) lsl 6
-           lor (Char.code text.[min (!i+2) (len-1)] land 0x3F), 3)
-        else
-          ((byte land 0x07) lsl 18
-           lor (Char.code text.[min (!i+1) (len-1)] land 0x3F) lsl 12
-           lor (Char.code text.[min (!i+2) (len-1)] land 0x3F) lsl 6
-           lor (Char.code text.[min (!i+3) (len-1)] land 0x3F), 4)
-      in
-      let gid = match Hashtbl.find_opt cmap_tbl cp with
-        | Some g -> g | None -> 0 in
-      let adv = match Hashtbl.find_opt hmtx_tbl gid with
-        | Some a -> a | None -> upm / 2 in
-      width := !width +. (float_of_int adv) *. scale;
-      i := !i + advance
-    done;
-    let ascent = size *. 0.8 in  (* approximate — could read OS/2 table *)
-    let descent = size *. 0.2 in
-    (!width, size, ascent, descent)
-
 
 (* ====================================================================== *)
 (* Output helpers                                                          *)
@@ -188,56 +71,6 @@ let rec serialize_value = function
     "(make-spread {" ^ String.concat " " items ^ "})"
   | _ -> "nil"
 
-(** Collect all ~-prefixed symbol references from an AST value.
-    Walks the tree recursively, returns a deduplicated list of symbol names
-    like ["~card"; "~layout/base"]. Used for dependency analysis. *)
-let collect_tilde_refs body =
-  let seen = Hashtbl.create 16 in
-  let rec walk = function
-    | Symbol s when String.length s > 0 && s.[0] = '~' ->
-      if not (Hashtbl.mem seen s) then Hashtbl.replace seen s ()
-    | List items | ListRef { contents = items } ->
-      List.iter walk items
-    | Dict d ->
-      Hashtbl.iter (fun _k v -> walk v) d
-    | Spread pairs ->
-      List.iter (fun (_k, v) -> walk v) pairs
-    | _ -> ()
-  in
-  walk body;
-  Hashtbl.fold (fun k () acc -> k :: acc) seen []
-
-(** Serialize a value to SX text, replacing ~-prefixed symbol references
-    with their content hashes from the index. Symbols not in the index
-    are emitted verbatim (unknown ref or non-component symbol). *)
-let rec serialize_value_hashed (index : (string, string) Hashtbl.t) = function
-  | Nil -> "nil"
-  | Bool true -> "true"
-  | Bool false -> "false"
-  | Number n ->
-    if Float.is_integer n then string_of_int (int_of_float n)
-    else Printf.sprintf "%g" n
-  | String s -> "\"" ^ escape_sx_string s ^ "\""
-  | Symbol s when String.length s > 0 && s.[0] = '~' ->
-    (match Hashtbl.find_opt index s with
-     | Some h -> "@h:" ^ h
-     | None -> s)
-  | Symbol s -> s
-  | Keyword k -> ":" ^ k
-  | List items | ListRef { contents = items } ->
-    "(" ^ String.concat " " (List.map (serialize_value_hashed index) items) ^ ")"
-  | Dict d ->
-    let pairs = Hashtbl.fold (fun k v acc ->
-      (Printf.sprintf ":%s %s" k (serialize_value_hashed index v)) :: acc) d [] in
-    "{" ^ String.concat " " (List.sort String.compare pairs) ^ "}"
-  | RawHTML s -> "\"" ^ escape_sx_string s ^ "\""
-  | SxExpr s -> s
-  | Spread pairs ->
-    let items = List.map (fun (k, v) ->
-      Printf.sprintf ":%s %s" k (serialize_value_hashed index v)) pairs in
-    "(make-spread {" ^ String.concat " " items ^ "})"
-  | _ -> "nil"
-
 (** Request epoch — monotonically increasing, set by (epoch N) from Python.
     All responses are tagged with the current epoch so Python can discard
     stale messages from previous requests. Makes pipe desync impossible. *)
@@ -316,11 +149,6 @@ let _scope_stacks = Sx_primitives._scope_stacks
 (* Populated from __app-config dict after SX files load.                *)
 let _app_config : (string, value) Hashtbl.t option ref = ref None
 let _defpage_paths : string list ref = ref []
-(* Streaming pages: path → page name, for pages with :stream true *)
-let _streaming_pages : (string, string) Hashtbl.t = Hashtbl.create 8
-(* Mutex to serialize streaming renders — OCaml threads share the runtime
-   lock, and concurrent CEK evaluations corrupt shared state. *)
-let _stream_mutex = Mutex.create ()
 
 let get_app_config key default =
   match !_app_config with
@@ -487,12 +315,12 @@ let resolve_library_path lib_spec =
     The file should contain a define-library form that registers itself. *)
 let _import_env : env option ref = ref None
 
-let rec load_library_file path =
-  (* Use eval_expr_io for IO-aware loading (handles nested imports) *)
+let load_library_file path =
+  (* Use eval_expr which has the cek_run import patch — handles nested imports *)
   let env = match !_import_env with Some e -> e | None -> Sx_types.make_env () in
   let exprs = Sx_parser.parse_file path in
   List.iter (fun expr ->
-    try ignore (eval_expr_io expr (Env env))
+    try ignore (Sx_ref.eval_expr expr (Env env))
     with Eval_error msg ->
       Printf.eprintf "[load-library] %s: %s\n%!" (Filename.basename path) msg
   ) exprs
@@ -500,7 +328,7 @@ let rec load_library_file path =
 (** IO-aware CEK run — handles suspension by dispatching IO requests.
     Import requests are handled locally (load .sx file).
     Other IO requests are sent to the Python bridge. *)
-and cek_run_with_io state =
+let cek_run_with_io state =
   let s = ref state in
   let is_terminal s = match Sx_ref.cek_terminal_p s with Bool true -> true | _ -> false in
   let is_suspended s = match Sx_runtime.get_val s (String "phase") with String "io-suspended" -> true | _ -> false in
@@ -527,24 +355,6 @@ and cek_run_with_io state =
                  (Sx_runtime.value_to_str lib_spec));
             Nil
           end
-        | "text-measure" ->
-          let args = let a = Sx_runtime.get_val request (String "args") in
-            (match a with List l -> l | _ -> [a]) in
-          let font = match args with String f :: _ -> f | _ -> "serif" in
-          let size = match args with
-            | [_font; Number sz; _text] -> sz
-            | [_font; Number sz] -> sz
-            | _ -> 16.0 in
-          let text = match args with
-            | [_font; _sz; String t] -> t
-            | _ -> "" in
-          let (w, h, asc, desc) = measure_text_otfm font size text in
-          let d = Hashtbl.create 4 in
-          Hashtbl.replace d "width" (Number w);
-          Hashtbl.replace d "height" (Number h);
-          Hashtbl.replace d "ascent" (Number asc);
-          Hashtbl.replace d "descent" (Number desc);
-          Dict d
         | _ ->
           let args = let a = Sx_runtime.get_val request (String "args") in
             (match a with List l -> l | _ -> [a]) in
@@ -558,7 +368,7 @@ and cek_run_with_io state =
   loop ()
 
 (** IO-aware eval_expr — like eval_expr but handles IO suspension. *)
-and eval_expr_io expr env =
+let _eval_expr_io expr env =
   let state = Sx_ref.make_cek_state expr env (List []) in
   cek_run_with_io state
 
@@ -1133,16 +943,7 @@ let register_jit_hook env =
          (try Some (Sx_vm.call_closure cl args cl.vm_env_ref)
           with
           | Sx_vm.VmSuspended (request, saved_vm) ->
-            (* Try inline IO resolution; fall back to suspend marker *)
-            (match !Sx_types._cek_io_resolver with
-             | Some resolver ->
-               let rec resolve_loop req vm =
-                 let result = resolver req (Nil) in
-                 (try Some (Sx_vm.resume_vm vm result)
-                  with Sx_vm.VmSuspended (req2, vm2) -> resolve_loop req2 vm2)
-               in
-               resolve_loop request saved_vm
-             | None -> Some (make_vm_suspend_marker request saved_vm))
+            Some (make_vm_suspend_marker request saved_vm)
           | e ->
             let fn_name = match l.l_name with Some n -> n | None -> "?" in
             if not (Hashtbl.mem _jit_warned fn_name) then begin
@@ -1167,15 +968,7 @@ let register_jit_hook env =
              (try Some (Sx_vm.call_closure cl args cl.vm_env_ref)
               with
               | Sx_vm.VmSuspended (request, saved_vm) ->
-                (match !Sx_types._cek_io_resolver with
-                 | Some resolver ->
-                   let rec resolve_loop req vm =
-                     let result = resolver req (Nil) in
-                     (try Some (Sx_vm.resume_vm vm result)
-                      with Sx_vm.VmSuspended (req2, vm2) -> resolve_loop req2 vm2)
-                   in
-                   resolve_loop request saved_vm
-                 | None -> Some (make_vm_suspend_marker request saved_vm))
+                Some (make_vm_suspend_marker request saved_vm)
               | e ->
                 Printf.eprintf "[jit] %s first-call fallback to CEK: %s\n%!" fn_name (Printexc.to_string e);
                 Hashtbl.replace _jit_warned fn_name true;
@@ -1201,41 +994,6 @@ let rebind_host_extensions env =
       | _ -> raise (Eval_error "register-special-form!: expected (name handler)")));
   ignore (env_bind env "*custom-special-forms*" Sx_ref.custom_special_forms)
 
-(* Path-based naming for unnamed definitions                               *)
-(* ====================================================================== *)
-
-let def_keywords = ["defcomp"; "defisland"; "defmacro"; "define";
-                     "defhandler"; "defstyle"; "deftype"; "defeffect";
-                     "defrelation"; "deftest"; "defpage"]
-
-(* Inject path-derived name into unnamed definitions.
-   (defcomp (params) body) -> (defcomp ~path/name (params) body)
-   Only applied when base_dir is provided (service components). *)
-let inject_path_name expr path base_dir =
-  match expr with
-  | List (Symbol kw :: rest) when List.mem kw def_keywords ->
-    (match rest with
-     | Symbol _ :: _ -> expr  (* Already named *)
-     | _ ->
-       (* Unnamed — derive name from file path relative to base_dir *)
-       let rel = if String.length path > String.length base_dir + 1
-         then String.sub path (String.length base_dir + 1)
-                (String.length path - String.length base_dir - 1)
-         else Filename.basename path in
-       let stem = if Filename.check_suffix rel ".sx"
-         then String.sub rel 0 (String.length rel - 3)
-         else rel in
-       (* index files are known by their directory *)
-       let name = if Filename.basename stem = "index"
-         then let d = Filename.dirname stem in
-              if d = "." then "index" else d
-         else stem in
-       (* Components/islands get ~ prefix *)
-       let prefixed = if kw = "defcomp" || kw = "defisland"
-         then "~" ^ name else name in
-       List (Symbol kw :: Symbol prefixed :: rest))
-  | _ -> expr
-
 (* Command dispatch                                                        *)
 (* ====================================================================== *)
 
@@ -1244,20 +1002,14 @@ let rec dispatch env cmd =
   | List [Symbol "ping"] ->
     send_ok_string "ocaml-cek"
 
-  | List [Symbol "load"; String path]
-  | List [Symbol "load"; String path; String _] ->
-    let base_dir = match cmd with
-      | List [_; _; String b] -> b | _ -> "" in
+  | List [Symbol "load"; String path] ->
     (try
       let exprs = Sx_parser.parse_file path in
       let prev_file = if Sx_types.env_has env "*current-file*" then Some (Sx_types.env_get env "*current-file*") else None in
       ignore (Sx_types.env_bind env "*current-file*" (String path));
       let count = ref 0 in
       List.iter (fun expr ->
-        let expr' = if base_dir <> "" then inject_path_name expr path base_dir else expr in
-        (try ignore (eval_expr_io expr' (Env env))
-         with Eval_error msg ->
-           Printf.eprintf "[load] %s: %s\n%!" (Filename.basename path) msg);
+        ignore (Sx_ref.eval_expr expr (Env env));
         incr count
       ) exprs;
       (* Rebind host extension points after .sx load — evaluator.sx
@@ -1988,32 +1740,6 @@ let http_response ?(status=200) ?(content_type="text/html; charset=utf-8") body
 let http_redirect url =
   Printf.sprintf "HTTP/1.1 301 Moved Permanently\r\nLocation: %s\r\nContent-Length: 0\r\nConnection: keep-alive\r\n\r\n" url
 
-(* Chunked transfer encoding helpers for streaming responses *)
-let http_chunked_header ?(status=200) ?(content_type="text/html; charset=utf-8") () =
-  let status_text = match status with
-    | 200 -> "OK" | 404 -> "Not Found" | 500 -> "Internal Server Error" | _ -> "Unknown" in
-  Printf.sprintf "HTTP/1.1 %d %s\r\nContent-Type: %s\r\nTransfer-Encoding: chunked\r\nConnection: keep-alive\r\nX-Accel-Buffering: no\r\nCache-Control: no-cache, no-transform\r\n\r\n"
-    status status_text content_type
-
-let write_chunk fd data =
-  if String.length data > 0 then begin
-    let chunk = Printf.sprintf "%x\r\n%s\r\n" (String.length data) data in
-    let bytes = Bytes.of_string chunk in
-    let total = Bytes.length bytes in
-    let written = ref 0 in
-    try
-      while !written < total do
-        let n = Unix.write fd bytes !written (total - !written) in
-        written := !written + n
-      done;
-      true
-    with Unix.Unix_error _ -> false
-  end else true
-
-let end_chunked fd =
-  (try ignore (Unix.write_substring fd "0\r\n\r\n" 0 5) with Unix.Unix_error _ -> ());
-  (try Unix.close fd with _ -> ())
-
 let parse_http_request data =
   match String.index_opt data '\r' with
   | None -> (match String.index_opt data '\n' with
@@ -2060,48 +1786,6 @@ let parse_http_headers data =
   ) (match lines with _ :: rest -> rest | [] -> []);
   !headers
 
-(* IO-aware eval for rendering — handles perform (text-measure, sleep, import).
-   Used by aser and SSR so components can call measure-text via perform. *)
-let eval_with_io_render expr env =
-  let state = ref (Sx_ref.cek_step_loop (Sx_ref.make_cek_state expr (Env env) Nil)) in
-  while sx_truthy (Sx_ref.cek_suspended_p !state) do
-    let request = Sx_ref.cek_io_request !state in
-    let op = match request with
-      | Dict d -> (match Hashtbl.find_opt d "op" with Some (String s) -> s | Some (Symbol s) -> s | _ -> "")
-      | _ -> "" in
-    let args = match request with
-      | Dict d -> (match Hashtbl.find_opt d "args" with Some v -> v | None -> Nil)
-      | _ -> Nil in
-    let result = match op with
-      | "text-measure" ->
-        let font = match args with
-          | List (String f :: _) -> f | _ -> "serif" in
-        let size = match args with
-          | List [_font; Number sz; _text] -> sz
-          | List [_font; Number sz] -> sz
-          | _ -> 16.0 in
-        let text = match args with
-          | List [_font; _sz; String t] -> t
-          | _ -> "" in
-        let (w, h, asc, desc) = measure_text_otfm font size text in
-        let d = Hashtbl.create 4 in
-        Hashtbl.replace d "width" (Number w);
-        Hashtbl.replace d "height" (Number h);
-        Hashtbl.replace d "ascent" (Number asc);
-        Hashtbl.replace d "descent" (Number desc);
-        Dict d
-      | "io-sleep" | "sleep" ->
-        let ms = match args with
-          | List (Number n :: _) -> n | Number n -> n | _ -> 0.0 in
-        Unix.sleepf (ms /. 1000.0); Nil
-      | "import" -> Nil
-      | _ -> Nil
-    in
-    state := Sx_ref.cek_step_loop (Sx_ref.cek_resume !state result)
-  done;
-  if sx_truthy (Sx_ref.cek_terminal_p !state) then Sx_ref.cek_value !state
-  else Nil
-
 (** Render a page. Routing + AJAX detection in SX (request-handler.sx),
     render pipeline (aser → SSR → shell) in OCaml for reliable env access. *)
 let http_render_page env path headers =
@@ -2153,7 +1837,7 @@ let http_render_page env path headers =
           (* AJAX: return SX wire format (aser output) with text/sx content type *)
           let body_result =
             let call = List [Symbol "aser"; List [Symbol "quote"; wrapped]; Env env] in
-            eval_with_io_render call env in
+            Sx_ref.eval_expr call (Env env) in
           let body_str = match body_result with
             | String s | SxExpr s -> s | _ -> serialize_value body_result in
           let t1 = Unix.gettimeofday () in
@@ -2167,7 +1851,7 @@ let http_render_page env path headers =
           let t1 = Unix.gettimeofday () in
           let body_result =
             let call = List [Symbol "aser"; List [Symbol "quote"; full_ast]; Env env] in
-            eval_with_io_render call env in
+            Sx_ref.eval_expr call (Env env) in
           let body_str = match body_result with
             | String s | SxExpr s -> s | _ -> serialize_value body_result in
           let t2 = Unix.gettimeofday () in
@@ -2177,7 +1861,7 @@ let http_render_page env path headers =
             if env_has env "render-to-html" then
               let render_call = List [Symbol "render-to-html";
                                       List [Symbol "quote"; body_expr]; Env env] in
-              (match eval_with_io_render render_call env with
+              (match Sx_ref.eval_expr render_call (Env env) with
                | String s | RawHTML s -> s | v -> Sx_runtime.value_to_str v)
             else Sx_render.sx_render_to_html env body_expr env
           with e -> Printf.eprintf "[http-ssr] failed for %s: %s\n%!" path (Printexc.to_string e); "" in
@@ -2189,7 +1873,6 @@ let http_render_page env path headers =
             Keyword "body-html"; String body_html;
             Keyword "component-defs"; get_shell "component-defs";
             Keyword "component-hash"; get_shell "component-hash";
-            Keyword "component-manifest"; get_shell "component-manifest";
             Keyword "pages-sx"; get_shell "pages-sx";
             Keyword "sx-css"; get_shell "sx-css";
             Keyword "asset-url"; get_shell "asset-url";
@@ -2217,297 +1900,6 @@ let http_render_page env path headers =
         end
       end
 
-(* JSON-encode a string for use in __sxResolve script tags *)
-let json_encode_string s =
-  let buf = Buffer.create (String.length s + 16) in
-  Buffer.add_char buf '"';
-  String.iter (fun c -> match c with
-    | '"' -> Buffer.add_string buf "\\\""
-    | '\\' -> Buffer.add_string buf "\\\\"
-    | '\n' -> Buffer.add_string buf "\\n"
-    | '\r' -> Buffer.add_string buf "\\r"
-    | '\t' -> Buffer.add_string buf "\\t"
-    | c when Char.code c < 0x20 ->
-      Buffer.add_string buf (Printf.sprintf "\\u%04x" (Char.code c))
-    | c -> Buffer.add_char buf c
-  ) s;
-  Buffer.add_char buf '"';
-  Buffer.contents buf
-
-(* Bootstrap script that queues resolves arriving before sx.js loads.
-   Must match _SX_STREAMING_BOOTSTRAP in shared/sx/helpers.py *)
-let _sx_streaming_bootstrap =
-  "<script>window.__sxPending=[];window.__sxResolve=function(i,s){\
-   if(window.Sx&&Sx.resolveSuspense){Sx.resolveSuspense(i,s)}\
-   else{window.__sxPending.push({id:i,sx:s})}}</script>"
-
-(* Build a resolve script tag. Must match _SX_STREAMING_RESOLVE in helpers.py *)
-let sx_streaming_resolve_script id sx_source =
-  Printf.sprintf "<script>window.__sxResolve&&window.__sxResolve(%s,%s)</script>"
-    (json_encode_string id) (json_encode_string sx_source)
-
-(* ====================================================================== *)
-(* IO-resolving evaluator for streaming render                             *)
-(* ====================================================================== *)
-
-(* Evaluate an expression with IO suspension handling.
-   Steps the CEK machine; when it suspends on an IO request, resolves
-   the request locally and resumes. Supports: io-sleep, import, helper. *)
-let eval_with_io expr env =
-  let state = ref (Sx_ref.cek_step_loop (Sx_ref.make_cek_state expr (Env env) Nil)) in
-  while sx_truthy (Sx_ref.cek_suspended_p !state) do
-    let request = Sx_ref.cek_io_request !state in
-    let op = match request with
-      | Dict d -> (match Hashtbl.find_opt d "op" with Some (String s) -> s | Some (Symbol s) -> s | _ -> "")
-      | _ -> "" in
-    let args = match request with
-      | Dict d -> (match Hashtbl.find_opt d "args" with Some v -> v | None -> Nil)
-      | _ -> Nil in
-    let result = match op with
-      | "io-sleep" | "sleep" ->
-        let ms = match args with
-          | List (Number n :: _) -> n
-          | Number n -> n
-          | _ -> 0.0 in
-        Unix.sleepf (ms /. 1000.0);
-        Nil
-      | "import" ->
-        (* Library import — delegate to existing import hook *)
-        (try
-          let lib_name = match request with
-            | Dict d -> (match Hashtbl.find_opt d "library" with Some v -> v | _ -> args)
-            | _ -> args in
-          ignore lib_name; (* import handled by _import_hook if registered *)
-          Nil
-        with _ -> Nil)
-      | "text-measure" ->
-        let font = match args with
-          | List (String f :: _) -> f | _ -> "serif" in
-        let size = match args with
-          | List [_font; Number sz; _text] -> sz
-          | List [_font; Number sz] -> sz
-          | _ -> 16.0 in
-        let text = match args with
-          | List [_font; _sz; String t] -> t
-          | _ -> "" in
-        let (w, h, asc, desc) = measure_text_otfm font size text in
-        let d = Hashtbl.create 4 in
-        Hashtbl.replace d "width" (Number w);
-        Hashtbl.replace d "height" (Number h);
-        Hashtbl.replace d "ascent" (Number asc);
-        Hashtbl.replace d "descent" (Number desc);
-        Dict d
-      | _ ->
-        Printf.eprintf "[io] unhandled IO op: %s\n%!" op;
-        Nil
-    in
-    state := Sx_ref.cek_step_loop (Sx_ref.cek_resume !state result)
-  done;
-  if sx_truthy (Sx_ref.cek_terminal_p !state) then Sx_ref.cek_value !state
-  else Nil
-
-(* ====================================================================== *)
-(* Streaming page render — shell-first with chunked transfer encoding      *)
-(* ====================================================================== *)
-
-let http_render_page_streaming env path _headers fd page_name =
-  (* No send timeout for streaming — the alive check in write_chunk handles
-     broken pipe. Streaming clients may be slow to receive large shell chunks
-     while busy parsing/downloading other resources. *)
-  (try Unix.setsockopt_float fd Unix.SO_SNDTIMEO 30.0 with _ -> ());
-  let t0 = Unix.gettimeofday () in
-  let page_def = try
-    match env_get env ("page:" ^ page_name) with Dict d -> d | _ -> raise Not_found
-  with _ ->
-    Printf.eprintf "[sx-stream] page def not found: page:%s\n%!" page_name;
-    let err = http_response ~status:500 "<h1>Streaming page def not found</h1>" in
-    let bytes = Bytes.of_string err in
-    (try ignore (Unix.write fd bytes 0 (Bytes.length bytes)) with _ -> ());
-    (try Unix.close fd with _ -> ());
-    raise Exit
-  in
-
-  (* Extract streaming fields from page def *)
-  let shell_ast = match Hashtbl.find_opt page_def "shell" with Some v -> v | None -> Nil in
-  let data_ast = match Hashtbl.find_opt page_def "data" with Some v -> v | None -> Nil in
-  let content_ast = match Hashtbl.find_opt page_def "content" with Some v -> v | None -> Nil in
-
-  (* Phase 1: Evaluate shell AST — contains ~suspense placeholders with fallbacks.
-     The :shell expression already includes the inner layout (e.g. ~layouts/doc),
-     so we only wrap in the outer layout (~shared:layout/app-body) for gutters.
-     NO inner layout wrapping — shell_ast already has it. *)
-  let shell_html = try
-    let outer_layout = get_app_str "outer-layout" "~shared:layout/app-body" in
-    let full_ast = List [Symbol outer_layout; Keyword "content"; shell_ast] in
-    let page_source = serialize_value full_ast in
-    (* aser → SSR *)
-    let body_result =
-      let call = List [Symbol "aser"; List [Symbol "quote"; full_ast]; Env env] in
-      Sx_ref.eval_expr call (Env env) in
-    let body_str = match body_result with
-      | String s | SxExpr s -> s | _ -> serialize_value body_result in
-    let body_html = try
-      let body_expr = match Sx_parser.parse_all body_str with
-        | [e] -> e | [] -> Nil | es -> List (Symbol "<>" :: es) in
-      if env_has env "render-to-html" then
-        let render_call = List [Symbol "render-to-html";
-                                List [Symbol "quote"; body_expr]; Env env] in
-        (match Sx_ref.eval_expr render_call (Env env) with
-         | String s | RawHTML s -> s | v -> Sx_runtime.value_to_str v)
-      else Sx_render.sx_render_to_html env body_expr env
-    with e -> Printf.eprintf "[sx-stream] SSR failed: %s\n%!" (Printexc.to_string e); "" in
-
-    (* Build full page shell with body HTML *)
-    let get_shell name = try env_get env ("__shell-" ^ name) with _ -> Nil in
-    let shell_args = [
-      Keyword "title"; String (get_app_str "title" "SX"); Keyword "csrf"; String "";
-      Keyword "page-sx"; String page_source;
-      Keyword "body-html"; String body_html;
-      Keyword "component-defs"; get_shell "component-defs";
-      Keyword "component-hash"; get_shell "component-hash";
-      Keyword "component-manifest"; get_shell "component-manifest";
-      Keyword "client-libs"; get_shell "client-libs";
-      Keyword "pages-sx"; get_shell "pages-sx";
-      Keyword "sx-css"; get_shell "sx-css";
-      Keyword "asset-url"; get_shell "asset-url";
-      Keyword "wasm-hash"; get_shell "wasm-hash";
-      Keyword "platform-hash"; get_shell "platform-hash";
-      Keyword "sxbc-hash"; get_shell "sxbc-hash";
-      Keyword "inline-css"; get_shell "inline-css";
-      Keyword "inline-head-js"; get_shell "inline-head-js";
-      Keyword "init-sx"; get_shell "init-sx";
-      Keyword "meta-html"; String "";
-    ] in
-    let shell_sym = get_app_str "shell" "~shared:shell/sx-page-shell" in
-    let shell_call = List (Symbol shell_sym :: shell_args) in
-    if env_has env "render-to-html" then
-      let render_call = List [Symbol "render-to-html";
-                              List [Symbol "quote"; shell_call]; Env env] in
-      (match Sx_ref.eval_expr render_call (Env env) with
-       | String s | RawHTML s -> s | v -> Sx_runtime.value_to_str v)
-    else Sx_render.sx_render_to_html env shell_call env
-  with e ->
-    Printf.eprintf "[sx-stream] shell render failed: %s\n%!" (Printexc.to_string e);
-    "<html><body><h1>Streaming shell render failed</h1></body></html>"
-  in
-  let t1 = Unix.gettimeofday () in
-
-  (* Phase 2: Send chunked header + shell HTML.
-     Strip closing </body></html> from shell — resolve scripts must go INSIDE
-     the body, otherwise the browser's HTML parser ignores them. *)
-  let shell_body, shell_tail =
-    (* Find last </body> and split there *)
-    let s = shell_html in
-    let body_close = "</body>" in
-    let rec find_last i found =
-      if i < 0 then found
-      else if i + String.length body_close <= String.length s
-              && String.sub s i (String.length body_close) = body_close
-      then find_last (i - 1) i
-      else find_last (i - 1) found
-    in
-    let pos = find_last (String.length s - String.length body_close) (-1) in
-    if pos >= 0 then
-      (String.sub s 0 pos, String.sub s pos (String.length s - pos))
-    else
-      (s, "")
-  in
-  let header = http_chunked_header () in
-  let header_bytes = Bytes.of_string header in
-  (try ignore (Unix.write fd header_bytes 0 (Bytes.length header_bytes)) with _ -> ());
-  let alive = ref true in
-  alive := write_chunk fd shell_body;
-  (* Bootstrap resolve script — must come after shell so suspense elements exist *)
-  if !alive then alive := write_chunk fd _sx_streaming_bootstrap;
-  let t2 = Unix.gettimeofday () in
-
-  (* Phase 3: Evaluate :data, render :content, flush resolve scripts.
-     Uses eval_with_io so :data expressions can perform IO (e.g. sleep, fetch).
-     Each data item is resolved independently — IO in one item doesn't block others
-     from being flushed as they complete. Bails out early on broken pipe. *)
-  let resolve_count = ref 0 in
-  if !alive && data_ast <> Nil && content_ast <> Nil then begin
-    (try
-      let data_result = eval_with_io data_ast env in
-      let t3_data = Unix.gettimeofday () in
-
-      (* Determine single-stream vs multi-stream *)
-      let data_items =
-        let extract_items items = List.map (fun item ->
-          let stream_id = match item with
-            | Dict d -> (match Hashtbl.find_opt d "stream-id" with
-              | Some (String s) -> s | _ -> "stream-content")
-            | _ -> "stream-content" in
-          (item, stream_id)) items in
-        match data_result with
-        | Dict _ -> [(data_result, "stream-content")]
-        | List items -> extract_items items
-        | ListRef { contents = items } -> extract_items items
-        | _ ->
-          Printf.eprintf "[sx-stream] :data returned %s, expected dict or list\n%!"
-            (Sx_runtime.type_of data_result |> Sx_runtime.value_to_str);
-          []
-      in
-
-      (* For each data item, bind values and render :content.
-         If the item has a "delay" field, perform IO sleep before resolving.
-         Each item flushes its resolve script independently — the client sees
-         content appear progressively as each IO completes. *)
-      List.iter (fun (item, stream_id) ->
-        if !alive then
-        (try
-          (* IO sleep if delay specified — demonstrates async streaming *)
-          (match item with
-           | Dict d -> (match Hashtbl.find_opt d "delay" with
-             | Some (Number ms) when ms > 0.0 ->
-               Printf.eprintf "[sx-stream] %s: sleeping %.0fms for IO...\n%!" stream_id ms;
-               Unix.sleepf (ms /. 1000.0)
-             | _ -> ())
-           | _ -> ());
-          (* Create fresh env with data bindings *)
-          let content_env = { bindings = Hashtbl.create 16; parent = Some env } in
-          (match item with
-           | Dict d ->
-             Hashtbl.iter (fun k v ->
-               if k <> "stream-id" && k <> "__type" && k <> "delay" then begin
-                 (* Normalize: underscores → hyphens *)
-                 let norm_k = String.map (fun c -> if c = '_' then '-' else c) k in
-                 ignore (env_bind content_env norm_k v);
-                 if norm_k <> k then ignore (env_bind content_env k v)
-               end
-             ) d
-           | _ -> ());
-
-          (* aser :content in the data-bound env — also with IO resolution *)
-          let content_result =
-            let call = List [Symbol "aser"; List [Symbol "quote"; content_ast]; Env content_env] in
-            eval_with_io call content_env in
-          let sx_source = match content_result with
-            | String s | SxExpr s -> s | _ -> serialize_value content_result in
-          let resolve_script = sx_streaming_resolve_script stream_id sx_source in
-          alive := write_chunk fd resolve_script;
-          incr resolve_count
-        with e ->
-          (* Error boundary: emit error fallback for this slot *)
-          let msg = Printexc.to_string e in
-          Printf.eprintf "[sx-stream] resolve error for %s: %s\n%!" stream_id msg;
-          let error_sx = Printf.sprintf "(div :class \"text-rose-600 p-4 text-sm\" \"Error: %s\")"
-            (String.map (fun c -> if c = '"' then '\'' else c) msg) in
-          alive := write_chunk fd (sx_streaming_resolve_script stream_id error_sx);
-          incr resolve_count)
-      ) data_items;
-      let t3 = Unix.gettimeofday () in
-      Printf.eprintf "[sx-stream] %s shell=%.3fs flush=%.3fs data=%.3fs resolve=%.3fs total=%.3fs chunks=%d\n%!"
-        path (t1 -. t0) (t2 -. t1) (t3_data -. t2) (t3 -. t3_data) (t3 -. t0) !resolve_count
-    with e ->
-      Printf.eprintf "[sx-stream] data eval failed: %s\n%!" (Printexc.to_string e))
-  end else
-    Printf.eprintf "[sx-stream] %s shell=%.3fs (no :data/:content)\n%!" path (t1 -. t0);
-
-  (* Phase 4: Send closing tags + end chunked response *)
-  if !alive && shell_tail <> "" then ignore (write_chunk fd shell_tail);
-  end_chunked fd
-
 (* ====================================================================== *)
 (* Static file serving + file hashing                                      *)
 (* ====================================================================== *)
@@ -2586,198 +1978,6 @@ let read_css_file path =
     In_channel.with_open_text path In_channel.input_all
   else ""
 
-(* ── Content-addressed hash index ────────────────────────────────
-   Merkle DAG over all definitions in env.bindings.
-   Each definition gets a SHA-256 hash of its *instantiated* form
-   (component references replaced with their hashes). *)
-
-type hash_index = {
-  name_to_hash : (string, string) Hashtbl.t;   (** "~card" → "a1b2c3..." *)
-  hash_to_def  : (string, string) Hashtbl.t;   (** hash → instantiated definition text *)
-  hash_to_name : (string, string) Hashtbl.t;   (** hash → "~card" *)
-  dependents   : (string, string list) Hashtbl.t; (** "~card" → ["~my-page", ...] *)
-} [@@warning "-69"]
-
-let _hash_index : hash_index option ref = ref None
-
-(** Canonical form for hashing — name excluded (it's the key, not content).
-    Includes params, affinity, has_children, and body with refs hashed. *)
-let canonical_form_component (index : (string, string) Hashtbl.t) c =
-  let ps = String.concat " " (
-    "&key" :: c.c_params @
-    (if c.c_has_children then ["&rest"; "children"] else [])) in
-  Printf.sprintf "(defcomp (%s) :affinity \"%s\" %s)"
-    ps c.c_affinity (serialize_value_hashed index c.c_body)
-
-let canonical_form_island (index : (string, string) Hashtbl.t) i =
-  let ps = String.concat " " (
-    "&key" :: i.i_params @
-    (if i.i_has_children then ["&rest"; "children"] else [])) in
-  Printf.sprintf "(defisland (%s) %s)"
-    ps (serialize_value_hashed index i.i_body)
-
-let canonical_form_macro (index : (string, string) Hashtbl.t) m =
-  let ps = String.concat " " (
-    m.m_params @
-    (match m.m_rest_param with Some r -> ["&rest"; r] | None -> [])) in
-  Printf.sprintf "(defmacro (%s) %s)"
-    ps (serialize_value_hashed index m.m_body)
-
-
-(** Compute truncated SHA-256 hash (16 hex chars = 64 bits). *)
-let hash_string s =
-  String.sub (Digest.string s |> Digest.to_hex) 0 16
-
-(** Build the Merkle hash index from env.bindings.
-    Topological sort: hash leaves first (no ~deps), propagate up. *)
-let build_hash_index env =
-  let name_to_hash = Hashtbl.create 256 in
-  let hash_to_def = Hashtbl.create 256 in
-  let hash_to_name = Hashtbl.create 256 in
-  let dependents = Hashtbl.create 256 in
-
-  (* Phase 0: hash client library source files as whole units.
-     Each file gets one hash. All (define name ...) forms in the file
-     map to that hash so any symbol triggers loading the whole file. *)
-  let project_dir = try Sys.getenv "SX_PROJECT_DIR" with Not_found -> "." in
-  let templates_dir = project_dir ^ "/shared/sx/templates" in
-  let client_lib_names = get_app_list "client-libs" ["tw-layout.sx"; "tw-type.sx"; "tw.sx"] in
-  List.iter (fun lib_name ->
-    let path = templates_dir ^ "/" ^ lib_name in
-    if Sys.file_exists path then begin
-      let src = In_channel.with_open_text path In_channel.input_all in
-      let h = hash_string src in
-      Hashtbl.replace hash_to_def h src;
-      (* Extract all (define name ...) forms and map each name to this hash *)
-      let exprs = try Sx_parser.parse_all src with _ -> [] in
-      let first_name = ref "" in
-      List.iter (fun expr ->
-        match expr with
-        | List (Symbol "define" :: Symbol name :: _) ->
-          Hashtbl.replace name_to_hash name h;
-          if !first_name = "" then first_name := name
-        | _ -> ()
-      ) exprs;
-      (* Map the hash to the first define name for debuggability *)
-      if !first_name <> "" then
-        Hashtbl.replace hash_to_name h !first_name
-    end
-  ) client_lib_names;
-
-  (* Phase 1: collect all component/island/macro definitions and their direct deps *)
-  let defs : (string * [ `Comp of component | `Island of island
-                        | `Macro of macro ]) list ref = ref [] in
-  let deps : (string, string list) Hashtbl.t = Hashtbl.create 256 in
-
-  Hashtbl.iter (fun sym v ->
-    let name = Sx_types.unintern sym in
-    match v with
-    | Component c when String.length name > 0 && name.[0] = '~' ->
-      let refs = collect_tilde_refs c.c_body in
-      defs := (name, `Comp c) :: !defs;
-      Hashtbl.replace deps name refs;
-      (* Register reverse deps *)
-      List.iter (fun dep ->
-        let prev = try Hashtbl.find dependents dep with Not_found -> [] in
-        Hashtbl.replace dependents dep (name :: prev)
-      ) refs
-    | Island i when String.length name > 0 && name.[0] = '~' ->
-      let refs = collect_tilde_refs i.i_body in
-      defs := (name, `Island i) :: !defs;
-      Hashtbl.replace deps name refs;
-      List.iter (fun dep ->
-        let prev = try Hashtbl.find dependents dep with Not_found -> [] in
-        Hashtbl.replace dependents dep (name :: prev)
-      ) refs
-    | Macro m when (match m.m_name with Some n -> String.length n > 0 | None -> false) ->
-      let refs = collect_tilde_refs m.m_body in
-      let mname = match m.m_name with Some n -> n | None -> name in
-      defs := (mname, `Macro m) :: !defs;
-      Hashtbl.replace deps mname refs;
-      List.iter (fun dep ->
-        let prev = try Hashtbl.find dependents dep with Not_found -> [] in
-        Hashtbl.replace dependents dep (mname :: prev)
-      ) refs
-    | _ -> ()
-  ) env.bindings;
-
-  (* Phase 2: Kahn's topological sort *)
-  let all_names = Hashtbl.create 256 in
-  List.iter (fun (name, _) -> Hashtbl.replace all_names name true) !defs;
-  (* In-degree: count how many of this def's deps are also in our set *)
-  let in_degree = Hashtbl.create 256 in
-  List.iter (fun (name, _) ->
-    let d = try Hashtbl.find deps name with Not_found -> [] in
-    let count = List.length (List.filter (fun dep -> Hashtbl.mem all_names dep) d) in
-    Hashtbl.replace in_degree name count
-  ) !defs;
-
-  (* Queue: all defs with in-degree 0 (leaves) *)
-  let queue = Queue.create () in
-  List.iter (fun (name, _) ->
-    if Hashtbl.find in_degree name = 0 then Queue.push name queue
-  ) !defs;
-
-  (* Lookup map for defs by name *)
-  let def_map = Hashtbl.create 256 in
-  List.iter (fun (name, def) -> Hashtbl.replace def_map name def) !defs;
-
-  let processed = ref 0 in
-
-  (* Phase 3: process in topological order *)
-  while not (Queue.is_empty queue) do
-    let name = Queue.pop queue in
-    incr processed;
-    (* All deps of this def are already hashed — compute canonical form *)
-    let canonical = match Hashtbl.find_opt def_map name with
-      | Some (`Comp c) -> canonical_form_component name_to_hash c
-      | Some (`Island i) -> canonical_form_island name_to_hash i
-      | Some (`Macro m) -> canonical_form_macro name_to_hash m
-      | None -> ""
-    in
-    if canonical <> "" then begin
-      let h = hash_string canonical in
-      Hashtbl.replace name_to_hash name h;
-      Hashtbl.replace hash_to_def h canonical;
-      Hashtbl.replace hash_to_name h name
-    end;
-    (* Decrease in-degree of dependents, enqueue if zero *)
-    let rev_deps = try Hashtbl.find dependents name with Not_found -> [] in
-    List.iter (fun dep_name ->
-      if Hashtbl.mem in_degree dep_name then begin
-        let d = Hashtbl.find in_degree dep_name in
-        Hashtbl.replace in_degree dep_name (d - 1);
-        if d - 1 = 0 then Queue.push dep_name queue
-      end
-    ) rev_deps
-  done;
-
-  (* Any remaining defs with in-degree > 0 have circular deps — hash without ref replacement *)
-  if !processed < List.length !defs then begin
-    List.iter (fun (name, _) ->
-      if not (Hashtbl.mem name_to_hash name) then begin
-        let canonical = match Hashtbl.find_opt def_map name with
-          | Some (`Comp c) -> canonical_form_component name_to_hash c
-          | Some (`Island i) -> canonical_form_island name_to_hash i
-          | Some (`Macro m) -> canonical_form_macro name_to_hash m
-          | None -> ""
-        in
-        if canonical <> "" then begin
-          let h = hash_string canonical in
-          Hashtbl.replace name_to_hash name h;
-          Hashtbl.replace hash_to_def h canonical;
-          Hashtbl.replace hash_to_name h name
-        end
-      end
-    ) !defs
-  end;
-
-  let idx = { name_to_hash; hash_to_def; hash_to_name; dependents } in
-  Printf.eprintf "[hash-index] %d definitions, %d hashes\n%!"
-    (List.length !defs) (Hashtbl.length name_to_hash);
-  _hash_index := Some idx;
-  idx
-
 
 (** Pre-compute shell statics and inject into env as __shell-* vars. *)
 let http_inject_shell_statics env static_dir sx_sxc =
@@ -2816,20 +2016,9 @@ let http_inject_shell_statics env static_dir sx_sxc =
   ) env.bindings;
   let raw_defs = Buffer.contents buf in
   (* Component-defs are inlined in <script type="text/sx">.
-     Escape </ → <\/ to prevent HTML parser from matching </script>. *)
-  let component_defs =
-    let len = String.length raw_defs in
-    let buf2 = Buffer.create (len + 64) in
-    for i = 0 to len - 1 do
-      if raw_defs.[i] = '<' && i + 1 < len && raw_defs.[i + 1] = '/' then begin
-        Buffer.add_string buf2 "<\\/";
-      end else if raw_defs.[i] = '/' && i > 0 && raw_defs.[i - 1] = '<' then
-        () (* skip — already handled above *)
-      else
-        Buffer.add_char buf2 raw_defs.[i]
-    done;
-    Buffer.contents buf2
-  in
+     The escape_sx_string function handles </ → <\\/ inside string
+     literals, preventing the HTML parser from matching </script>. *)
+  let component_defs = raw_defs in
   let component_hash = Digest.string component_defs |> Digest.to_hex in
   (* Compute per-file hashes for cache busting *)
   let wasm_hash = file_hash (static_dir ^ "/wasm/sx_browser.bc.wasm.js") in
@@ -2841,74 +2030,6 @@ let http_inject_shell_statics env static_dir sx_sxc =
     read_css_file (static_dir ^ "/styles/" ^ name)) css_file_names) in
   ignore (env_bind env "__shell-component-defs" (String component_defs));
   ignore (env_bind env "__shell-component-hash" (String component_hash));
-  (* Build content-addressed hash index *)
-  let hidx = build_hash_index env in
-  (* Hash each .sxbc module individually and add to the hash index.
-     Each module's content is stored by hash; exported symbols map to the module hash. *)
-  let sxbc_dir = static_dir ^ "/wasm/sx" in
-  let module_manifest_path = sxbc_dir ^ "/module-manifest.sx" in
-  let module_hashes : (string, string) Hashtbl.t = Hashtbl.create 32 in (* module key → hash *)
-  (if Sys.file_exists module_manifest_path then begin
-    (* Read each .sxbc file, hash it, store in hash_to_def *)
-    if Sys.file_exists sxbc_dir && Sys.is_directory sxbc_dir then begin
-      let files = Array.to_list (Sys.readdir sxbc_dir) in
-      let sxbc_files = List.filter (fun f -> Filename.check_suffix f ".sxbc") files in
-      List.iter (fun fname ->
-        let fpath = sxbc_dir ^ "/" ^ fname in
-        let content = In_channel.with_open_bin fpath In_channel.input_all in
-        let h = hash_string content in
-        Hashtbl.replace hidx.hash_to_def h content;
-        Hashtbl.replace hidx.hash_to_name h fname;
-        (* Map filename (without ext) to hash for the modules section *)
-        Hashtbl.replace module_hashes fname h
-      ) sxbc_files
-    end
-  end);
-  (* Hash the WASM bootstrap files — these are the kernel scripts
-     that must load before anything else. *)
-  let wasm_dir = static_dir ^ "/wasm" in
-  let boot_files = ["sx_browser.bc.wasm.js"; "sx-platform.js"] in
-  let boot_hashes = List.filter_map (fun fname ->
-    let fpath = wasm_dir ^ "/" ^ fname in
-    if Sys.file_exists fpath then begin
-      let content = In_channel.with_open_bin fpath In_channel.input_all in
-      let h = hash_string content in
-      Hashtbl.replace hidx.hash_to_def h content;
-      Hashtbl.replace hidx.hash_to_name h fname;
-      Some (fname, h)
-    end else None
-  ) boot_files in
-  Printf.eprintf "[hash-index] %d module hashes, %d boot hashes\n%!"
-    (Hashtbl.length module_hashes) (List.length boot_hashes);
-  (* Build full manifest JSON:
-     {"v":1,"defs":{...},"modules":{...},"boot":[["file","hash"],...]} *)
-  let manifest_buf = Buffer.create 8192 in
-  Buffer.add_string manifest_buf "{\"v\":1,\"defs\":{";
-  let first = ref true in
-  Hashtbl.iter (fun name hash ->
-    if not !first then Buffer.add_char manifest_buf ',';
-    first := false;
-    Buffer.add_string manifest_buf (Printf.sprintf "\"%s\":\"%s\""
-      (escape_sx_string name) hash)
-  ) hidx.name_to_hash;
-  Buffer.add_string manifest_buf "},\"modules\":{";
-  first := true;
-  Hashtbl.iter (fun fname hash ->
-    if not !first then Buffer.add_char manifest_buf ',';
-    first := false;
-    Buffer.add_string manifest_buf (Printf.sprintf "\"%s\":\"%s\""
-      (escape_sx_string fname) hash)
-  ) module_hashes;
-  Buffer.add_string manifest_buf "},\"boot\":[";
-  first := true;
-  List.iter (fun (_fname, h) ->
-    if not !first then Buffer.add_char manifest_buf ',';
-    first := false;
-    Buffer.add_string manifest_buf (Printf.sprintf "\"%s\"" h)
-  ) boot_hashes;
-  Buffer.add_string manifest_buf "]}";
-  let manifest_json = Buffer.contents manifest_buf in
-  ignore (env_bind env "__shell-component-manifest" (String manifest_json));
   (* Build minimal pages-sx from defpage definitions in loaded .sx files.
      Scans all loaded .sx files in the component dirs for (defpage ...) forms. *)
   let pages_buf = Buffer.create 4096 in
@@ -2935,12 +2056,8 @@ let http_inject_shell_statics env static_dir sx_sxc =
                     | Some v -> serialize_value v | _ -> "" in
                   let has_data = match extract_kw "data" rest with
                     | Some _ -> true | None -> false in
-                  let is_stream = match extract_kw "stream" rest with
-                    | Some (Symbol "true") | Some (Bool true) -> true | _ -> false in
                   if path_val <> "" then begin
                     _defpage_paths := path_val :: !_defpage_paths;
-                    if is_stream then
-                      Hashtbl.replace _streaming_pages path_val name;
                     Buffer.add_string pages_buf
                       (Printf.sprintf "{:name \"%s\" :path \"%s\" :auth \"public\" :has-data %s :content \"%s\"}\n"
                         name path_val (if has_data then "true" else "false")
@@ -2957,9 +2074,6 @@ let http_inject_shell_statics env static_dir sx_sxc =
   Printf.eprintf "[sx-http] pages-sx: %d bytes (%d lines)\n%!"
     (String.length pages_sx)
     (List.length (String.split_on_char '\n' pages_sx));
-  if Hashtbl.length _streaming_pages > 0 then
-    Printf.eprintf "[sx-http] streaming pages: %s\n%!"
-      (String.concat ", " (Hashtbl.fold (fun p n acc -> (p ^ "→" ^ n) :: acc) _streaming_pages []));
   ignore (env_bind env "__shell-pages-sx" (String pages_sx));
   ignore (env_bind env "__shell-sx-css" (String sx_css));
   ignore (env_bind env "__shell-asset-url" (String "/static"));
@@ -3102,23 +2216,16 @@ let http_setup_platform_constructors env =
     | [Env e] -> List (Hashtbl.fold (fun k _v acc -> String (Sx_types.unintern k) :: acc) e.bindings [])
     | _ -> List [])
 
-let http_load_files ?(base_dir="") env files =
-  (* Like cli_load_files but tolerant — logs errors, doesn't crash.
-     When base_dir is set, unnamed definitions get path-derived names. *)
+let http_load_files env files =
+  (* Like cli_load_files but tolerant — logs errors, doesn't crash *)
   List.iter (fun path ->
     if Sys.file_exists path then begin
       try
-        let prev_file = if Sx_types.env_has env "*current-file*" then Some (Sx_types.env_get env "*current-file*") else None in
-        ignore (Sx_types.env_bind env "*current-file*" (String path));
         let exprs = Sx_parser.parse_file path in
         List.iter (fun expr ->
-          let expr' = if base_dir <> "" then inject_path_name expr path base_dir else expr in
-          try ignore (eval_expr_io expr' (Env env))
+          try ignore (Sx_ref.eval_expr expr (Env env))
           with e -> Printf.eprintf "[http-load] %s: %s\n%!" (Filename.basename path) (Printexc.to_string e)
-        ) exprs;
-        (match prev_file with
-         | Some v -> ignore (Sx_types.env_bind env "*current-file*" v)
-         | None -> ())
+        ) exprs
       with e -> Printf.eprintf "[http-load] parse error %s: %s\n%!" path (Printexc.to_string e)
     end
   ) files;
@@ -3407,17 +2514,6 @@ let http_setup_page_helpers env =
       with _ -> String (";; component " ^ name ^ " not found"))
     | _ -> raise (Eval_error "component-source: expected (name)"));
 
-  (* IO sleep primitive — used by streaming pages to simulate async IO delays.
-     Application code calls (io-sleep ms) which raises CekPerformRequest;
-     the streaming render's eval_with_io resolves it with Unix.sleepf. *)
-  bind "io-sleep" (fun args ->
-    let ms = match args with Number n :: _ -> n | _ -> 0.0 in
-    raise (Sx_types.CekPerformRequest (
-      let d = Hashtbl.create 2 in
-      Hashtbl.replace d "op" (String "io-sleep");
-      Hashtbl.replace d "args" (List [Number ms]);
-      Dict d)));
-
   ignore bind (* suppress unused warning *)
 
 let http_mode port =
@@ -3481,8 +2577,8 @@ let http_mode port =
   (* Files to skip — declarative metadata, not needed for rendering *)
   let skip_files = ["primitives.sx"; "types.sx"; "boundary.sx";
                      "harness.sx"; "eval-rules.sx"; "vm-inline.sx"] in
-  let skip_dirs = ["tests"; "test"; "plans"; "essays"; "spec"; "client-libs"; "_test"] in
-  let rec load_dir ?(base="") dir =
+  let skip_dirs = ["tests"; "test"; "plans"; "essays"; "spec"; "client-libs"] in
+  let rec load_dir dir =
     if Sys.file_exists dir && Sys.is_directory dir then begin
       let entries = Sys.readdir dir in
       Array.sort String.compare entries;
@@ -3490,13 +2586,13 @@ let http_mode port =
         let path = dir ^ "/" ^ f in
         if Sys.is_directory path then begin
           if not (List.mem f skip_dirs) then
-            load_dir ~base path
+            load_dir path
         end
         else if Filename.check_suffix f ".sx"
                 && not (List.mem f skip_files)
                 && not (String.length f > 5 && String.sub f 0 5 = "test-")
                 && not (Filename.check_suffix f ".test.sx") then
-          http_load_files ~base_dir:base env [path]
+          http_load_files env [path]
       ) entries
     end
   in
@@ -3507,8 +2603,8 @@ let http_mode port =
     let docker_path = project_dir ^ "/sxc" in
     let dev_path = project_dir ^ "/sx/sxc" in
     if Sys.file_exists docker_path then docker_path else dev_path in
-  load_dir ~base:sx_sxc sx_sxc;
-  load_dir ~base:sx_sx sx_sx;
+  load_dir sx_sxc;
+  load_dir sx_sx;
   let t1 = Unix.gettimeofday () in
   Printf.eprintf "[sx-http] All files loaded in %.3fs\n%!" (t1 -. t0);
   (* Derive batchable_helpers from __io-registry *)
@@ -3577,10 +2673,11 @@ let http_mode port =
     | _ -> raise (Eval_error "component-source: expected (name)"));
   let jt0 = Unix.gettimeofday () in
   let count = ref 0 in
-  (* Pre-compile the entire compiler — compile + helpers.
-     jit_compile_lambda calls compile directly via the VM when it has
-     bytecode, so all helper calls happen in one VM execution. *)
-  let compiler_names = [
+  (* Skip JIT pre-compilation — causes make-spread/assoc issues.
+     Pure CEK eval is stable. ~6s first render, ~1s subsequent. *)
+  let compiler_names : string list = [
+  ] in
+  let _compiler_names_disabled = [
     "compile"; "compile-module"; "compile-expr"; "compile-symbol";
     "compile-dict"; "compile-list"; "compile-if"; "compile-when";
     "compile-and"; "compile-or"; "compile-begin"; "compile-let";
@@ -3611,6 +2708,10 @@ let http_mode port =
      narrower SX versions. The native assoc handles variadic key/value pairs
      which evaluator.sx requires. *)
   rebind_host_extensions env;
+  (* Sync host-only bindings to VM globals for CALL_PRIM *)
+  List.iter (fun name ->
+    try Hashtbl.replace _shared_vm_globals name (env_get env name) with _ -> ()
+  ) ["make-spread"; "assoc"; "expand-components?"; "make-spread-string"];
   ignore (env_bind env "assoc" (NativeFn ("assoc", fun args ->
     match args with
     | Dict d :: rest ->
@@ -3638,7 +2739,6 @@ let http_mode port =
     let dev_path = project_dir ^ "/shared/static" in
     if Sys.file_exists docker_path then docker_path else dev_path in
   Printf.eprintf "[sx-http] static_dir=%s\n%!" static_dir;
-  _font_base := static_dir ^ "/fonts";
   (* HTTP mode always expands components — bind once, shared across domains *)
   ignore (env_bind env "expand-components?" (NativeFn ("expand-components?", fun _args -> Bool true)));
   (* Inject shell statics with real file hashes, CSS, and pages registry *)
@@ -3647,41 +2747,6 @@ let http_mode port =
      The env_bind hook keeps it in sync with any future bindings. *)
   (* Enable lazy JIT — compile lambdas to bytecode on first call *)
   register_jit_hook env;
-  (* Install global IO resolver so perform works inside aser/eval_expr.
-     This lets components call measure-text during server-side rendering. *)
-  Sx_types._cek_io_resolver := Some (fun request _state ->
-    (* Extract op and args from either Dict {op, args} or raw List/ListRef (op-symbol args...) *)
-    let op, args = match request with
-      | Dict d ->
-        let o = match Hashtbl.find_opt d "op" with Some (String s) -> s | Some (Symbol s) -> s | _ -> "" in
-        let a = match Hashtbl.find_opt d "args" with Some v -> v | None -> Nil in
-        (o, a)
-      | List (Symbol op_sym :: rest) | ListRef { contents = Symbol op_sym :: rest } -> (op_sym, List rest)
-      | List (String op_str :: rest) | ListRef { contents = String op_str :: rest } -> (op_str, List rest)
-      | _ -> ("", Nil)
-    in
-    match op with
-    | "text-measure" ->
-      let font = match args with
-        | List (String f :: _) -> f
-        | _ -> "serif" in
-      let size = match args with
-        | List [_font; Number sz; _text] -> sz
-        | List [_font; Number sz] -> sz
-        | _ -> 16.0 in
-      let text = match args with
-        | List [_font; _sz; String t] -> t
-        | _ -> "" in
-      let (width, height, ascent, descent) = measure_text_otfm font size text in
-      let d = Hashtbl.create 4 in
-      Hashtbl.replace d "width" (Number width);
-      Hashtbl.replace d "height" (Number height);
-      Hashtbl.replace d "ascent" (Number ascent);
-      Hashtbl.replace d "descent" (Number descent);
-      Dict d
-    | "io-sleep" | "sleep" -> Nil
-    | "import" -> Nil
-    | _ -> Nil);
   (* Response cache — path → full HTTP response string.
      Populated during pre-warm, serves cached responses in <0.1ms.
      Thread-safe: reads are lock-free (Hashtbl.find_opt is atomic for
@@ -3979,135 +3044,9 @@ let http_mode port =
                   (escape_sx_string (Printexc.to_string e)))
           in
           write_response fd response; true
-        end else if is_sx && String.length path > 6 && String.sub path 0 6 = "/sx/h/" then begin
-          let rest = String.sub path 6 (String.length path - 6) in
-          (* WASM companion assets: /sx/h/sx_browser.bc.wasm.assets/... → /static/wasm/... *)
-          if String.length rest > 26 && String.sub rest 0 26 = "sx_browser.bc.wasm.assets/" then begin
-            let asset_path = "/static/wasm/" ^ rest in
-            write_response fd (serve_static_file static_dir asset_path); true
-          end else begin
-          (* Content-addressed definition endpoint: /sx/h/{hash} *)
-          let hash = rest in
-          let resp = match !_hash_index with
-            | Some idx ->
-              (match Hashtbl.find_opt idx.hash_to_def hash with
-               | Some def ->
-                 let name = match Hashtbl.find_opt idx.hash_to_name hash with
-                   | Some n -> n | None -> "?" in
-                 (* Detect content type from filename *)
-                 let is_js = Filename.check_suffix name ".js" in
-                 let ct = if is_js then "application/javascript"
-                          else "text/sx; charset=utf-8" in
-                 let body = if is_js then def
-                            else Printf.sprintf ";; %s\n%s" name def in
-                 Printf.sprintf
-                   "HTTP/1.1 200 OK\r\n\
-                    Content-Type: %s\r\n\
-                    Content-Length: %d\r\n\
-                    Cache-Control: public, max-age=31536000, immutable\r\n\
-                    Access-Control-Allow-Origin: *\r\n\
-                    Connection: keep-alive\r\n\r\n%s"
-                   ct (String.length body) body
-               | None ->
-                 http_response ~status:404 "unknown hash")
-            | None ->
-              http_response ~status:503 "hash index not built"
-          in
-          write_response fd resp; true
-          end (* inner begin for hash vs wasm-assets *)
         end else if is_sx then begin
-          (* Streaming pages: chunked transfer, bypass cache.
-             Convert SX URL to flat defpage path:
-               /sx/(geography.(isomorphism.streaming)) → /geography/isomorphism/streaming
-             Strip prefix, remove parens, replace dots with slashes. *)
-          let page_path =
-            let raw = if String.length path > app_prefix_len
-              && String.sub path 0 app_prefix_len = app_prefix
-              then String.sub path app_prefix_len (String.length path - app_prefix_len)
-              else path in
-            let buf = Buffer.create (String.length raw + 1) in
-            Buffer.add_char buf '/';
-            String.iter (fun c -> match c with
-              | '(' | ')' -> ()
-              | '.' -> Buffer.add_char buf '/'
-              | c -> Buffer.add_char buf c
-            ) raw;
-            Buffer.contents buf in
-          let stream_page_name = Hashtbl.find_opt _streaming_pages page_path in
-          if stream_page_name <> None then begin
-            let sname = match stream_page_name with Some s -> s | None -> "" in
-            if is_ajax then begin
-              (* AJAX streaming: evaluate shell + data + content synchronously,
-                 return fully-resolved SX wire format (no chunked transfer). *)
-              let response = try
-                let page_def = match env_get env ("page:" ^ sname) with Dict d -> d | _ -> raise Not_found in
-                let shell_ast = match Hashtbl.find_opt page_def "shell" with Some v -> v | None -> Nil in
-                let data_ast = match Hashtbl.find_opt page_def "data" with Some v -> v | None -> Nil in
-                let content_ast = match Hashtbl.find_opt page_def "content" with Some v -> v | None -> Nil in
-                (* Evaluate shell — provides nav + suspense skeletons *)
-                let shell_sx =
-                  let call = List [Symbol "aser"; List [Symbol "quote"; shell_ast]; Env env] in
-                  match Sx_ref.eval_expr call (Env env) with
-                  | String s | SxExpr s -> s | v -> serialize_value v in
-                (* If we have data+content, resolve all slots and embed as OOB swaps *)
-                let resolve_oob = if data_ast <> Nil && content_ast <> Nil then begin
-                  let data_result = try Sx_ref.eval_expr data_ast (Env env) with _ -> Nil in
-                  let extract_sid items = List.map (fun item ->
-                    let sid = match item with Dict d ->
-                      (match Hashtbl.find_opt d "stream-id" with Some (String s) -> s | _ -> "stream-content")
-                      | _ -> "stream-content" in (item, sid)) items in
-                  let data_items = match data_result with
-                    | Dict _ -> [(data_result, "stream-content")]
-                    | List items -> extract_sid items
-                    | ListRef { contents = items } -> extract_sid items
-                    | _ -> [] in
-                  let buf = Buffer.create 1024 in
-                  List.iter (fun (item, stream_id) ->
-                    try
-                      let cenv = { bindings = Hashtbl.create 16; parent = Some env } in
-                      (match item with Dict d ->
-                        Hashtbl.iter (fun k v ->
-                          if k <> "stream-id" && k <> "__type" then begin
-                            let nk = String.map (fun c -> if c = '_' then '-' else c) k in
-                            ignore (env_bind cenv nk v);
-                            if nk <> k then ignore (env_bind cenv k v)
-                          end) d | _ -> ());
-                      let cr = let call = List [Symbol "aser"; List [Symbol "quote"; content_ast]; Env cenv] in
-                        Sx_ref.eval_expr call (Env cenv) in
-                      let sx_src = match cr with String s | SxExpr s -> s | v -> serialize_value v in
-                      (* OOB swap: replace suspense placeholder contents *)
-                      Buffer.add_string buf
-                        (Printf.sprintf "(div :id \"sx-suspense-%s\" :data-suspense \"%s\" :sx-swap-oob \"innerHTML\" :style \"display:contents\" %s)"
-                          stream_id stream_id sx_src)
-                    with e ->
-                      Printf.eprintf "[sx-stream-ajax] resolve error %s: %s\n%!" stream_id (Printexc.to_string e)
-                  ) data_items;
-                  Buffer.contents buf
-                end else "" in
-                http_response ~content_type:"text/sx; charset=utf-8" (shell_sx ^ resolve_oob)
-              with e ->
-                Printf.eprintf "[sx-stream-ajax] error for %s: %s\n%!" path (Printexc.to_string e);
-                http_response ~status:500 ~content_type:"text/sx; charset=utf-8"
-                  (Printf.sprintf "(div :class \"p-4 text-rose-600\" \"Streaming page error: %s\")"
-                    (escape_sx_string (Printexc.to_string e)))
-              in
-              write_response fd response; true
-            end else begin
-              (* Full page streaming: run in a thread so the accept loop
-                 stays unblocked for concurrent requests. *)
-              let _t = Thread.create (fun () ->
-                (try http_render_page_streaming env path [] fd sname
-                 with Exit -> ()
-                    | e -> Printf.eprintf "[sx-stream] unexpected error for %s: %s\n%!" path (Printexc.to_string e);
-                           (try Unix.close fd with _ -> ()))
-              ) () in
-              true
-            end
-          end else
-          let has_state_cookie = Hashtbl.mem _request_cookies "sx-home-stepper" in
           let cache_key = if is_ajax then "ajax:" ^ path else path in
-          match (if has_state_cookie then None
-                 else Hashtbl.find_opt response_cache cache_key) with
+          match Hashtbl.find_opt response_cache cache_key with
           | Some cached -> write_response fd cached; true
           | None ->
             if is_ajax then begin
@@ -4128,18 +3067,6 @@ let http_mode port =
                       (escape_sx_string (Printexc.to_string e)))
               in
               write_response fd response; true
-            end else if has_state_cookie then begin
-              (* State cookie present — render on main thread so get-cookie works.
-                 Don't cache: response varies by cookie value. *)
-              let response =
-                try match http_render_page env path [] with
-                  | Some body -> http_response body
-                  | None -> http_response ~status:404 "<h1>Not Found</h1>"
-                with e ->
-                  Printf.eprintf "[render] Cookie render error for %s: %s\n%!" path (Printexc.to_string e);
-                  http_response ~status:500 "<h1>Error</h1>"
-              in
-              write_response fd response; true
             end else begin
               (* Full page: queue to render worker *)
               Mutex.lock render_mutex;
@@ -4253,163 +3180,6 @@ let http_mode port =
     Array.iter Domain.join workers)
 
 
-(* --site mode: full site env (same setup as HTTP) + epoch protocol on stdin/stdout.
-   No HTTP server, no ports. Used by Playwright sandbox tests to render pages
-   as a pure function: URL → HTML via the render-page epoch command. *)
-let site_mode () =
-  let env = make_server_env () in
-  http_setup_declarative_stubs env;
-  http_setup_platform_constructors env;
-  http_setup_page_helpers env;
-  (* Load all .sx files — same as http_mode *)
-  let project_dir = try Sys.getenv "SX_PROJECT_DIR" with Not_found ->
-    Sys.getcwd () in
-  let spec_base = project_dir ^ "/spec" in
-  let lib_base = project_dir ^ "/lib" in
-  let web_base = project_dir ^ "/web" in
-  let shared_sx = try Sys.getenv "SX_SHARED_DIR" with Not_found ->
-    let docker_path = project_dir ^ "/shared_sx" in
-    let dev_path = project_dir ^ "/shared/sx/templates" in
-    if Sys.file_exists docker_path then docker_path else dev_path in
-  let sx_sx = try Sys.getenv "SX_COMPONENTS_DIR" with Not_found ->
-    let docker_path = project_dir ^ "/components" in
-    let dev_path = project_dir ^ "/sx/sx" in
-    if Sys.file_exists docker_path then docker_path else dev_path in
-  let static_dir = try Sys.getenv "SX_STATIC_DIR" with Not_found ->
-    let docker_path = project_dir ^ "/static" in
-    let dev_path = project_dir ^ "/shared/static" in
-    if Sys.file_exists docker_path then docker_path else dev_path in
-  ignore (env_bind env "_project-dir" (String project_dir));
-  ignore (env_bind env "_spec-dir" (String spec_base));
-  ignore (env_bind env "_lib-dir" (String lib_base));
-  ignore (env_bind env "_web-dir" (String web_base));
-  _font_base := static_dir ^ "/fonts";
-  _import_env := Some env;
-  let core_files = [
-    spec_base ^ "/parser.sx"; spec_base ^ "/render.sx"; spec_base ^ "/signals.sx";
-    lib_base ^ "/compiler.sx";
-    web_base ^ "/adapter-html.sx"; web_base ^ "/adapter-sx.sx";
-    web_base ^ "/io.sx"; web_base ^ "/web-forms.sx"; web_base ^ "/engine.sx";
-    web_base ^ "/request-handler.sx"; web_base ^ "/page-helpers.sx";
-  ] in
-  http_load_files env core_files;
-  let skip_files = ["primitives.sx"; "types.sx"; "boundary.sx";
-                     "harness.sx"; "eval-rules.sx"; "vm-inline.sx"] in
-  let skip_dirs = ["tests"; "test"; "plans"; "essays"; "spec"; "client-libs"] in
-  let rec load_dir ?(base="") dir =
-    if Sys.file_exists dir && Sys.is_directory dir then begin
-      let entries = Sys.readdir dir in
-      Array.sort String.compare entries;
-      Array.iter (fun f ->
-        let path = dir ^ "/" ^ f in
-        if Sys.is_directory path then begin
-          if not (List.mem f skip_dirs) then load_dir ~base path
-        end
-        else if Filename.check_suffix f ".sx"
-                && not (List.mem f skip_files)
-                && not (String.length f > 5 && String.sub f 0 5 = "test-")
-                && not (Filename.check_suffix f ".test.sx") then
-          http_load_files ~base_dir:base env [path]
-      ) entries
-    end
-  in
-  load_dir lib_base;
-  load_dir shared_sx;
-  let sx_sxc = try Sys.getenv "SX_SXC_DIR" with Not_found ->
-    let docker_path = project_dir ^ "/sxc" in
-    let dev_path = project_dir ^ "/sx/sxc" in
-    if Sys.file_exists docker_path then docker_path else dev_path in
-  load_dir ~base:sx_sxc sx_sxc;
-  load_dir ~base:sx_sx sx_sx;
-  (* IO registry + app config *)
-  (try match env_get env "__io-registry" with
-    | Dict registry ->
-      let batchable = Hashtbl.fold (fun name entry acc ->
-        match entry with
-        | Dict d -> (match Hashtbl.find_opt d "batchable" with
-          | Some (Bool true) -> name :: acc | _ -> acc)
-        | _ -> acc) registry [] in
-      if batchable <> [] then batchable_helpers := batchable
-    | _ -> ()
-  with _ -> ());
-  (try match env_get env "__app-config" with
-    | Dict d -> _app_config := Some d
-    | _ -> ()
-  with _ -> ());
-  (* SSR overrides *)
-  let bind name fn = ignore (env_bind env name (NativeFn (name, fn))) in
-  bind "effect" (fun _args -> Nil);
-  bind "register-in-scope" (fun _args -> Nil);
-  rebind_host_extensions env;
-  ignore (env_bind env "assoc" (NativeFn ("assoc", fun args ->
-    match args with
-    | Dict d :: rest ->
-      let d2 = Hashtbl.copy d in
-      let rec go = function
-        | [] -> Dict d2
-        | String k :: v :: rest -> Hashtbl.replace d2 k v; go rest
-        | Keyword k :: v :: rest -> Hashtbl.replace d2 k v; go rest
-        | _ -> raise (Eval_error "assoc: pairs")
-      in go rest
-    | _ -> raise (Eval_error "assoc: dict + pairs"))));
-  ignore (env_bind env "expand-components?" (NativeFn ("expand-components?", fun _args -> Bool true)));
-  (* Shell statics for render-page *)
-  http_inject_shell_statics env static_dir sx_sxc;
-  (* No JIT in site mode — the lazy JIT hook can loop on complex ASTs
-     (known bug: project_jit_bytecode_bug.md). Pure CEK is slower but
-     correct. First renders take ~2-5s, subsequent ~0.5-1s with caching. *)
-  Printf.eprintf "[site] Ready — epoch protocol on stdin/stdout\n%!";
-  send "(ready)";
-  (* nav-urls helper — walk sx-nav-tree, collect (href label) pairs *)
-  let nav_urls () =
-    let tree = env_get env "sx-nav-tree" in
-    let urls = ref [] in
-    let rec walk node = match node with
-      | Dict d ->
-        let href = match Hashtbl.find_opt d "href" with Some (String s) -> s | _ -> "" in
-        let label = match Hashtbl.find_opt d "label" with Some (String s) -> s | _ -> "" in
-        if href <> "" then urls := (href, label) :: !urls;
-        (match Hashtbl.find_opt d "children" with
-         | Some (List items) | Some (ListRef { contents = items }) ->
-           List.iter walk items
-         | _ -> ())
-      | _ -> ()
-    in
-    walk tree;
-    let items = List.rev !urls in
-    "(" ^ String.concat " " (List.map (fun (h, l) ->
-      Printf.sprintf "(\"%s\" \"%s\")" (escape_sx_string h) (escape_sx_string l)
-    ) items) ^ ")"
-  in
-  (* Epoch protocol loop *)
-  (try
-    while true do
-      match read_line_blocking () with
-      | None -> exit 0
-      | Some line ->
-        let line = String.trim line in
-        if line = "" then ()
-        else begin
-          let exprs = Sx_parser.parse_all line in
-          match exprs with
-          | [List [Symbol "epoch"; Number n]] ->
-            current_epoch := int_of_float n
-          (* render-page: full SSR pipeline — URL → complete HTML *)
-          | [List [Symbol "render-page"; String path]] ->
-            (try match http_render_page env path [] with
-              | Some html -> send_ok_blob html
-              | None -> send_error ("render-page: no route for " ^ path)
-            with e -> send_error ("render-page: " ^ Printexc.to_string e))
-          (* nav-urls: flat list of (href label) from nav tree *)
-          | [List [Symbol "nav-urls"]] ->
-            (try send_ok_raw (nav_urls ())
-            with e -> send_error ("nav-urls: " ^ Printexc.to_string e))
-          | [cmd] -> dispatch env cmd
-          | _ -> send_error ("Expected single command, got " ^ string_of_int (List.length exprs))
-        end
-    done
-  with End_of_file -> ())
-
 let () =
   (* Check for CLI mode flags *)
   let args = Array.to_list Sys.argv in
@@ -4417,7 +3187,6 @@ let () =
   else if List.mem "--render" args then cli_mode "render"
   else if List.mem "--aser-slot" args then cli_mode "aser-slot"
   else if List.mem "--aser" args then cli_mode "aser"
-  else if List.mem "--site" args then site_mode ()
   else if List.mem "--http" args then begin
     (* Extract port: --http PORT *)
     let port = ref 8014 in
diff --git a/hosts/ocaml/lib/sx_ref.ml b/hosts/ocaml/lib/sx_ref.ml
index 78f5cd34..ad1bb896 100644
--- a/hosts/ocaml/lib/sx_ref.ml
+++ b/hosts/ocaml/lib/sx_ref.ml
@@ -738,7 +738,9 @@ and bind_import_set import_set env =
 
 (* step-sf-import *)
 and step_sf_import args env kont =
-  (if sx_truthy ((empty_p (args))) then (make_cek_value (Nil) (env) (kont)) else (let import_set = (first (args)) in let rest_sets = (rest (args)) in (let lib_spec = (let head = (if sx_truthy ((let _and = (list_p (import_set)) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p (import_set)))))) in if not (sx_truthy _and) then _and else (symbol_p ((first (import_set))))))) then (symbol_name ((first (import_set)))) else Nil) in (if sx_truthy ((let _or = (prim_call "=" [head; (String "only")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [head; (String "except")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [head; (String "prefix")]) in if sx_truthy _or then _or else (prim_call "=" [head; (String "rename")]))))) then (nth (import_set) ((Number 1.0))) else import_set)) in (if sx_truthy ((library_loaded_p (lib_spec))) then (let () = ignore ((bind_import_set (import_set) (env))) in (if sx_truthy ((empty_p (rest_sets))) then (make_cek_value (Nil) (env) (kont)) else (step_sf_import (rest_sets) (env) (kont)))) else (make_cek_suspended ((let _d = Hashtbl.create 2 in Hashtbl.replace _d "library" lib_spec; Hashtbl.replace _d "op" (String "import"); Dict _d)) (env) ((kont_push ((make_import_frame (import_set) (rest_sets) (env))) (kont))))))))
+  (if sx_truthy ((empty_p (args))) then (make_cek_value (Nil) (env) (kont)) else (let import_set = (first (args)) in let rest_sets = (rest (args)) in (let lib_spec = (let head = (if sx_truthy ((let _and = (list_p (import_set)) in if not (sx_truthy _and) then _and else (let _and = (Bool (not (sx_truthy ((empty_p (import_set)))))) in if not (sx_truthy _and) then _and else (symbol_p ((first (import_set))))))) then (symbol_name ((first (import_set)))) else Nil) in (if sx_truthy ((let _or = (prim_call "=" [head; (String "only")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [head; (String "except")]) in if sx_truthy _or then _or else (let _or = (prim_call "=" [head; (String "prefix")]) in if sx_truthy _or then _or else (prim_call "=" [head; (String "rename")]))))) then (nth (import_set) ((Number 1.0))) else import_set)) in (if sx_truthy ((library_loaded_p (lib_spec))) then (let () = ignore ((bind_import_set (import_set) (env))) in (if sx_truthy ((empty_p (rest_sets))) then (make_cek_value (Nil) (env) (kont)) else (step_sf_import (rest_sets) (env) (kont)))) else (let hook_loaded = match !Sx_types._import_hook with Some hook -> hook lib_spec | None -> false in
+  if hook_loaded then (let () = ignore ((bind_import_set (import_set) (env))) in (if sx_truthy ((empty_p (rest_sets))) then (make_cek_value (Nil) (env) (kont)) else (step_sf_import (rest_sets) (env) (kont))))
+  else (make_cek_suspended ((let _d = Hashtbl.create 2 in Hashtbl.replace _d "library" lib_spec; Hashtbl.replace _d "op" (String "import"); Dict _d)) (env) ((kont_push ((make_import_frame (import_set) (rest_sets) (env))) (kont)))))))))
 
 (* step-sf-perform *)
 and step_sf_perform args env kont =
diff --git a/lib/hyperscript/compiler.sx b/lib/hyperscript/compiler.sx
index d8eadd64..6a47db8e 100644
--- a/lib/hyperscript/compiler.sx
+++ b/lib/hyperscript/compiler.sx
@@ -237,6 +237,20 @@
                 (quote hs-repeat-times)
                 mode
                 (list (quote fn) (list) body)))
+            ((and (list? mode) (= (first mode) (quote while)))
+              (let
+                ((cond-expr (hs-to-sx (nth mode 1))))
+                (list
+                  (quote hs-repeat-while)
+                  (list (quote fn) (list) cond-expr)
+                  (list (quote fn) (list) body))))
+            ((and (list? mode) (= (first mode) (quote until)))
+              (let
+                ((cond-expr (hs-to-sx (nth mode 1))))
+                (list
+                  (quote hs-repeat-until)
+                  (list (quote fn) (list) cond-expr)
+                  (list (quote fn) (list) body))))
             (true
               (list
                 (quote hs-repeat-times)
@@ -1035,7 +1049,15 @@
                   ((fn-expr (hs-to-sx (nth ast 1)))
                     (args (map hs-to-sx (nth ast 2))))
                   (cons fn-expr args)))
-              ((= head (quote return)) (hs-to-sx (nth ast 1)))
+              ((= head (quote return))
+                (let
+                  ((val (nth ast 1)))
+                  (if
+                    (nil? val)
+                    (list (quote raise) (list (quote list) "hs-return" nil))
+                    (list
+                      (quote raise)
+                      (list (quote list) "hs-return" (hs-to-sx val))))))
               ((= head (quote throw))
                 (list (quote raise) (hs-to-sx (nth ast 1))))
               ((= head (quote settle))
@@ -1106,13 +1128,41 @@
                   (quote hs-init)
                   (list (quote fn) (list) (hs-to-sx (nth ast 1)))))
               ((= head (quote def))
-                (list
-                  (quote define)
-                  (make-symbol (nth ast 1))
+                (let
+                  ((body (hs-to-sx (nth ast 3)))
+                    (params
+                      (map
+                        (fn
+                          (p)
+                          (if
+                            (and (list? p) (= (first p) (quote ref)))
+                            (make-symbol (nth p 1))
+                            (make-symbol p)))
+                        (nth ast 2))))
                   (list
-                    (quote fn)
-                    (map make-symbol (nth ast 2))
-                    (hs-to-sx (nth ast 3)))))
+                    (quote define)
+                    (make-symbol (nth ast 1))
+                    (list
+                      (quote fn)
+                      params
+                      (list
+                        (quote guard)
+                        (list
+                          (quote _e)
+                          (list
+                            (quote true)
+                            (list
+                              (quote if)
+                              (list
+                                (quote and)
+                                (list (quote list?) (quote _e))
+                                (list
+                                  (quote =)
+                                  (list (quote first) (quote _e))
+                                  "hs-return"))
+                              (list (quote nth) (quote _e) 1)
+                              (list (quote raise) (quote _e)))))
+                        body)))))
               ((= head (quote behavior)) (emit-behavior ast))
               ((= head (quote sx-eval))
                 (let
diff --git a/lib/hyperscript/parser.sx b/lib/hyperscript/parser.sx
index 6ac177e7..a2cfd02a 100644
--- a/lib/hyperscript/parser.sx
+++ b/lib/hyperscript/parser.sx
@@ -1041,7 +1041,7 @@
           (let
             ((cnd (parse-expr)))
             (let
-              ((then-body (parse-cmd-list)))
+              ((then-body (do (match-kw "then") (parse-cmd-list))))
               (let
                 ((else-body (if (or (match-kw "else") (match-kw "otherwise")) (parse-cmd-list) nil)))
                 (match-kw "end")
diff --git a/lib/hyperscript/runtime.sx b/lib/hyperscript/runtime.sx
index 5739bc08..7379936e 100644
--- a/lib/hyperscript/runtime.sx
+++ b/lib/hyperscript/runtime.sx
@@ -275,6 +275,12 @@
     (define do-forever (fn () (thunk) (do-forever)))
     (do-forever)))
 
+(define
+  hs-repeat-while
+  (fn
+    (cond-fn thunk)
+    (when (cond-fn) (thunk) (hs-repeat-while cond-fn thunk))))
+
 (define
   hs-fetch
   (fn
@@ -426,6 +432,10 @@
     (dom-set-style target prop (str to-val))
     (when duration (hs-settle target))))
 
+
+
+
+
 (define
   hs-type-check
   (fn
@@ -446,37 +456,33 @@
             (= (host-typeof value) "text")))
         (true (= (host-typeof value) (downcase type-name)))))))
 
-
-
-
-
 (define
   hs-type-check-strict
   (fn
     (value type-name)
     (if (nil? value) false (hs-type-check value type-name))))
-
-(define
-  hs-strict-eq
-  (fn (a b) (and (= (type-of a) (type-of b)) (= a b))))
 ;; ── Sandbox/test runtime additions ──────────────────────────────
 ;; Property access — dot notation and .length
+(define
+  hs-strict-eq
+  (fn (a b) (and (= (type-of a) (type-of b)) (= a b))))
+;; DOM query stub — sandbox returns empty list
 (define
   hs-eq-ignore-case
   (fn (a b) (= (downcase (str a)) (downcase (str b)))))
-;; DOM query stub — sandbox returns empty list
+;; Method dispatch — obj.method(args)
 (define
   hs-starts-with-ic?
   (fn (str prefix) (starts-with? (downcase str) (downcase prefix))))
-;; Method dispatch — obj.method(args)
+
+;; ── 0.9.90 features ─────────────────────────────────────────────
+;; beep! — debug logging, returns value unchanged
 (define
   hs-contains-ignore-case?
   (fn
     (haystack needle)
     (contains? (downcase (str haystack)) (downcase (str needle)))))
-
-;; ── 0.9.90 features ─────────────────────────────────────────────
-;; beep! — debug logging, returns value unchanged
+;; Property-based is — check obj.key truthiness
 (define
   hs-falsy?
   (fn
@@ -488,7 +494,7 @@
       ((and (list? v) (= (len v) 0)) true)
       ((= v 0) true)
       (true false))))
-;; Property-based is — check obj.key truthiness
+;; Array slicing (inclusive both ends)
 (define
   hs-matches?
   (fn
@@ -499,7 +505,7 @@
       ((= (host-typeof target) "element")
         (if (string? pattern) (host-call target "matches" pattern) false))
       (true false))))
-;; Array slicing (inclusive both ends)
+;; Collection: sorted by
 (define
   hs-contains?
   (fn
@@ -519,9 +525,9 @@
               true
               (hs-contains? (rest collection) item)))))
       (true false))))
-;; Collection: sorted by
-(define precedes? (fn (a b) (< (str a) (str b))))
 ;; Collection: sorted by descending
+(define precedes? (fn (a b) (< (str a) (str b))))
+;; Collection: split by
 (define
   hs-empty?
   (fn
@@ -532,7 +538,7 @@
       ((list? v) (= (len v) 0))
       ((dict? v) (= (len (keys v)) 0))
       (true false))))
-;; Collection: split by
+;; Collection: joined by
 (define
   hs-empty-target!
   (fn
@@ -557,7 +563,7 @@
                 ((children (host-call target "querySelectorAll" "input, textarea, select")))
                 (for-each (fn (el) (hs-empty-target! el)) children)))
             (true (dom-set-inner-html target ""))))))))
-;; Collection: joined by
+
 (define
   hs-open!
   (fn
diff --git a/shared/static/wasm/sx/hs-compiler.sx b/shared/static/wasm/sx/hs-compiler.sx
index d8eadd64..6a47db8e 100644
--- a/shared/static/wasm/sx/hs-compiler.sx
+++ b/shared/static/wasm/sx/hs-compiler.sx
@@ -237,6 +237,20 @@
                 (quote hs-repeat-times)
                 mode
                 (list (quote fn) (list) body)))
+            ((and (list? mode) (= (first mode) (quote while)))
+              (let
+                ((cond-expr (hs-to-sx (nth mode 1))))
+                (list
+                  (quote hs-repeat-while)
+                  (list (quote fn) (list) cond-expr)
+                  (list (quote fn) (list) body))))
+            ((and (list? mode) (= (first mode) (quote until)))
+              (let
+                ((cond-expr (hs-to-sx (nth mode 1))))
+                (list
+                  (quote hs-repeat-until)
+                  (list (quote fn) (list) cond-expr)
+                  (list (quote fn) (list) body))))
             (true
               (list
                 (quote hs-repeat-times)
@@ -1035,7 +1049,15 @@
                   ((fn-expr (hs-to-sx (nth ast 1)))
                     (args (map hs-to-sx (nth ast 2))))
                   (cons fn-expr args)))
-              ((= head (quote return)) (hs-to-sx (nth ast 1)))
+              ((= head (quote return))
+                (let
+                  ((val (nth ast 1)))
+                  (if
+                    (nil? val)
+                    (list (quote raise) (list (quote list) "hs-return" nil))
+                    (list
+                      (quote raise)
+                      (list (quote list) "hs-return" (hs-to-sx val))))))
               ((= head (quote throw))
                 (list (quote raise) (hs-to-sx (nth ast 1))))
               ((= head (quote settle))
@@ -1106,13 +1128,41 @@
                   (quote hs-init)
                   (list (quote fn) (list) (hs-to-sx (nth ast 1)))))
               ((= head (quote def))
-                (list
-                  (quote define)
-                  (make-symbol (nth ast 1))
+                (let
+                  ((body (hs-to-sx (nth ast 3)))
+                    (params
+                      (map
+                        (fn
+                          (p)
+                          (if
+                            (and (list? p) (= (first p) (quote ref)))
+                            (make-symbol (nth p 1))
+                            (make-symbol p)))
+                        (nth ast 2))))
                   (list
-                    (quote fn)
-                    (map make-symbol (nth ast 2))
-                    (hs-to-sx (nth ast 3)))))
+                    (quote define)
+                    (make-symbol (nth ast 1))
+                    (list
+                      (quote fn)
+                      params
+                      (list
+                        (quote guard)
+                        (list
+                          (quote _e)
+                          (list
+                            (quote true)
+                            (list
+                              (quote if)
+                              (list
+                                (quote and)
+                                (list (quote list?) (quote _e))
+                                (list
+                                  (quote =)
+                                  (list (quote first) (quote _e))
+                                  "hs-return"))
+                              (list (quote nth) (quote _e) 1)
+                              (list (quote raise) (quote _e)))))
+                        body)))))
               ((= head (quote behavior)) (emit-behavior ast))
               ((= head (quote sx-eval))
                 (let
diff --git a/shared/static/wasm/sx/hs-parser.sx b/shared/static/wasm/sx/hs-parser.sx
index 6ac177e7..a2cfd02a 100644
--- a/shared/static/wasm/sx/hs-parser.sx
+++ b/shared/static/wasm/sx/hs-parser.sx
@@ -1041,7 +1041,7 @@
           (let
             ((cnd (parse-expr)))
             (let
-              ((then-body (parse-cmd-list)))
+              ((then-body (do (match-kw "then") (parse-cmd-list))))
               (let
                 ((else-body (if (or (match-kw "else") (match-kw "otherwise")) (parse-cmd-list) nil)))
                 (match-kw "end")
diff --git a/shared/static/wasm/sx/hs-runtime.sx b/shared/static/wasm/sx/hs-runtime.sx
index 5739bc08..7379936e 100644
--- a/shared/static/wasm/sx/hs-runtime.sx
+++ b/shared/static/wasm/sx/hs-runtime.sx
@@ -275,6 +275,12 @@
     (define do-forever (fn () (thunk) (do-forever)))
     (do-forever)))
 
+(define
+  hs-repeat-while
+  (fn
+    (cond-fn thunk)
+    (when (cond-fn) (thunk) (hs-repeat-while cond-fn thunk))))
+
 (define
   hs-fetch
   (fn
@@ -426,6 +432,10 @@
     (dom-set-style target prop (str to-val))
     (when duration (hs-settle target))))
 
+
+
+
+
 (define
   hs-type-check
   (fn
@@ -446,37 +456,33 @@
             (= (host-typeof value) "text")))
         (true (= (host-typeof value) (downcase type-name)))))))
 
-
-
-
-
 (define
   hs-type-check-strict
   (fn
     (value type-name)
     (if (nil? value) false (hs-type-check value type-name))))
-
-(define
-  hs-strict-eq
-  (fn (a b) (and (= (type-of a) (type-of b)) (= a b))))
 ;; ── Sandbox/test runtime additions ──────────────────────────────
 ;; Property access — dot notation and .length
+(define
+  hs-strict-eq
+  (fn (a b) (and (= (type-of a) (type-of b)) (= a b))))
+;; DOM query stub — sandbox returns empty list
 (define
   hs-eq-ignore-case
   (fn (a b) (= (downcase (str a)) (downcase (str b)))))
-;; DOM query stub — sandbox returns empty list
+;; Method dispatch — obj.method(args)
 (define
   hs-starts-with-ic?
   (fn (str prefix) (starts-with? (downcase str) (downcase prefix))))
-;; Method dispatch — obj.method(args)
+
+;; ── 0.9.90 features ─────────────────────────────────────────────
+;; beep! — debug logging, returns value unchanged
 (define
   hs-contains-ignore-case?
   (fn
     (haystack needle)
     (contains? (downcase (str haystack)) (downcase (str needle)))))
-
-;; ── 0.9.90 features ─────────────────────────────────────────────
-;; beep! — debug logging, returns value unchanged
+;; Property-based is — check obj.key truthiness
 (define
   hs-falsy?
   (fn
@@ -488,7 +494,7 @@
       ((and (list? v) (= (len v) 0)) true)
       ((= v 0) true)
       (true false))))
-;; Property-based is — check obj.key truthiness
+;; Array slicing (inclusive both ends)
 (define
   hs-matches?
   (fn
@@ -499,7 +505,7 @@
       ((= (host-typeof target) "element")
         (if (string? pattern) (host-call target "matches" pattern) false))
       (true false))))
-;; Array slicing (inclusive both ends)
+;; Collection: sorted by
 (define
   hs-contains?
   (fn
@@ -519,9 +525,9 @@
               true
               (hs-contains? (rest collection) item)))))
       (true false))))
-;; Collection: sorted by
-(define precedes? (fn (a b) (< (str a) (str b))))
 ;; Collection: sorted by descending
+(define precedes? (fn (a b) (< (str a) (str b))))
+;; Collection: split by
 (define
   hs-empty?
   (fn
@@ -532,7 +538,7 @@
       ((list? v) (= (len v) 0))
       ((dict? v) (= (len (keys v)) 0))
       (true false))))
-;; Collection: split by
+;; Collection: joined by
 (define
   hs-empty-target!
   (fn
@@ -557,7 +563,7 @@
                 ((children (host-call target "querySelectorAll" "input, textarea, select")))
                 (for-each (fn (el) (hs-empty-target! el)) children)))
             (true (dom-set-inner-html target ""))))))))
-;; Collection: joined by
+
 (define
   hs-open!
   (fn
diff --git a/tests/playwright/hs-behavioral.spec.js b/tests/playwright/hs-behavioral.spec.js
index fc1a6857..74e8d545 100644
--- a/tests/playwright/hs-behavioral.spec.js
+++ b/tests/playwright/hs-behavioral.spec.js
@@ -1,11 +1,10 @@
 // @ts-check
 /**
- * Hyperscript behavioral tests — SX tests in Playwright sandbox.
+ * Hyperscript behavioral tests — SX tests running in Playwright sandbox.
  *
- * Tests are registered during file load (deferred), then each is run
- * individually via page.evaluate with a 3s Promise.race timeout.
- * Hanging tests fail with TIMEOUT. After a timeout, the page is
- * closed and a fresh one is created to avoid cascading hangs.
+ * Loads the WASM kernel + hs stack, defines the test platform,
+ * loads test-framework.sx + test-hyperscript-behavioral.sx,
+ * and reports each test individually.
  */
 const { test, expect } = require('playwright/test');
 const fs = require('fs');
@@ -15,41 +14,32 @@ const PROJECT_ROOT = path.resolve(__dirname, '../..');
 const WASM_DIR = path.join(PROJECT_ROOT, 'shared/static/wasm');
 const SX_DIR = path.join(WASM_DIR, 'sx');
 
-const WEB_MODULES = [
-  'render', 'core-signals', 'signals', 'deps', 'router',
-  'page-helpers', 'freeze', 'dom', 'browser',
-  'adapter-html', 'adapter-sx', 'adapter-dom',
-  'boot-helpers', 'hypersx', 'engine', 'orchestration', 'boot',
-];
-const HS_MODULES = [
-  'hs-tokenizer', 'hs-parser', 'hs-compiler', 'hs-runtime', 'hs-integration',
-];
+const SANDBOX_STACKS = {
+  web: [
+    'render', 'core-signals', 'signals', 'deps', 'router',
+    'page-helpers', 'freeze', 'dom', 'browser',
+    'adapter-html', 'adapter-sx', 'adapter-dom',
+    'boot-helpers', 'hypersx', 'engine', 'orchestration', 'boot',
+  ],
+  hs: [
+    'hs-tokenizer', 'hs-parser', 'hs-compiler', 'hs-runtime', 'hs-integration',
+  ],
+};
 
-// Cache module sources — avoid re-reading files on reboot
-const MODULE_CACHE = {};
-function getModuleSrc(mod) {
-  if (MODULE_CACHE[mod]) return MODULE_CACHE[mod];
-  const sxPath = path.join(SX_DIR, mod + '.sx');
-  const libPath = path.join(PROJECT_ROOT, 'lib/hyperscript', mod.replace(/^hs-/, '') + '.sx');
-  try {
-    MODULE_CACHE[mod] = fs.existsSync(sxPath) ? fs.readFileSync(sxPath, 'utf8') : fs.readFileSync(libPath, 'utf8');
-  } catch(e) { MODULE_CACHE[mod] = null; }
-  return MODULE_CACHE[mod];
-}
-
-// Cache test file sources
-const TEST_FILES = ['spec/harness.sx', 'spec/tests/test-framework.sx', 'spec/tests/test-hyperscript-behavioral.sx'];
-const TEST_FILE_CACHE = {};
-for (const f of TEST_FILES) {
-  TEST_FILE_CACHE[f] = fs.readFileSync(path.join(PROJECT_ROOT, f), 'utf8');
-}
-
-async function bootSandbox(page) {
+/**
+ * Boot WASM kernel with hs stack, define test platform, load test files.
+ * Returns array of {suite, name, pass, error} for each test.
+ */
+async function runSxTests(page) {
   await page.goto('about:blank');
+  await page.evaluate(() => { document.body.innerHTML = ''; });
+
+  // Inject WASM kernel
   const kernelSrc = fs.readFileSync(path.join(WASM_DIR, 'sx_browser.bc.js'), 'utf8');
   await page.addScriptTag({ content: kernelSrc });
   await page.waitForFunction('!!window.SxKernel', { timeout: 10000 });
 
+  // Register FFI + IO driver
   await page.evaluate(() => {
     const K = window.SxKernel;
     K.registerNative('host-global', a => { const n=a[0]; return (n in globalThis)?globalThis[n]:null; });
@@ -69,7 +59,11 @@ async function bootSandbox(page) {
       const fn=a[0];
       if(typeof fn==='function'&&fn.__sx_handle===undefined)return fn;
       if(fn&&fn.__sx_handle!==undefined){
-        return function(){const r=K.callFn(fn,Array.from(arguments));if(window._driveAsync)window._driveAsync(r);return r;};
+        return function(){
+          const r=K.callFn(fn,Array.from(arguments));
+          if(window._driveAsync)window._driveAsync(r);
+          return r;
+        };
       }
       return function(){};
     });
@@ -81,260 +75,211 @@ async function bootSandbox(page) {
       return typeof o;
     });
     K.registerNative('host-await', a => {
-      const[p,cb]=a;if(p&&typeof p.then==='function'){const f=(cb&&cb.__sx_handle!==undefined)?v=>K.callFn(cb,[v]):()=>{};p.then(f);}
+      const[p,cb]=a;
+      if(p&&typeof p.then==='function'){
+        const f=(cb&&cb.__sx_handle!==undefined)?v=>K.callFn(cb,[v]):()=>{};
+        p.then(f);
+      }
     });
     K.registerNative('load-library!', () => false);
+
+    // IO suspension driver
+    window._ioTrace = [];
+    window._asyncPending = 0;
     window._driveAsync = function driveAsync(result) {
       if(!result||!result.suspended)return;
-      const req=result.request;const items=req&&(req.items||req);
-      const op=items&&items[0];const opName=typeof op==='string'?op:(op&&op.name)||String(op);
+      window._asyncPending++;
+      const req=result.request; const items=req&&(req.items||req);
+      const op=items&&items[0]; const opName=typeof op==='string'?op:(op&&op.name)||String(op);
       const arg=items&&items[1];
-      function doResume(val,delay){setTimeout(()=>{try{const r=result.resume(val);driveAsync(r);}catch(e){}},delay);}
+      function doResume(val,delay){
+        setTimeout(()=>{
+          try{const r=result.resume(val);window._asyncPending--;driveAsync(r);}
+          catch(e){window._asyncPending--;}
+        },delay);
+      }
       if(opName==='io-sleep'||opName==='wait')doResume(null,Math.min(typeof arg==='number'?arg:0,10));
+      else if(opName==='io-navigate')window._asyncPending--;
       else if(opName==='io-fetch')doResume({ok:true,text:''},1);
+      else window._asyncPending--;
     };
+
     K.eval('(define SX_VERSION "hs-test-1.0")');
     K.eval('(define SX_ENGINE "ocaml-vm-sandbox")');
     K.eval('(define parse sx-parse)');
     K.eval('(define serialize sx-serialize)');
   });
 
+  // Load web + hs modules
+  const allModules = [...SANDBOX_STACKS.web, ...SANDBOX_STACKS.hs];
   const loadErrors = [];
-  await page.evaluate(() => { if (window.SxKernel.beginModuleLoad) window.SxKernel.beginModuleLoad(); });
-  for (const mod of [...WEB_MODULES, ...HS_MODULES]) {
-    const src = getModuleSrc(mod);
-    if (!src) { loadErrors.push(mod); continue; }
+
+  await page.evaluate(() => {
+    if (window.SxKernel.beginModuleLoad) window.SxKernel.beginModuleLoad();
+  });
+
+  for (const mod of allModules) {
+    const sxPath = path.join(SX_DIR, mod + '.sx');
+    const libPath = path.join(PROJECT_ROOT, 'lib/hyperscript', mod.replace(/^hs-/, '') + '.sx');
+    let src;
+    try {
+      src = fs.existsSync(sxPath) ? fs.readFileSync(sxPath, 'utf8') : fs.readFileSync(libPath, 'utf8');
+    } catch(e) { loadErrors.push(mod + ': file not found'); continue; }
     const err = await page.evaluate(s => {
-      try { window.SxKernel.load(s); return null; } catch(e) { return e.message; }
+      try { window.SxKernel.load(s); return null; }
+      catch(e) { return e.message; }
     }, src);
     if (err) loadErrors.push(mod + ': ' + err);
   }
-  await page.evaluate(() => { if (window.SxKernel.endModuleLoad) window.SxKernel.endModuleLoad(); });
 
-  // Deferred test registration + helpers
   await page.evaluate(() => {
-    const K = window.SxKernel;
-    K.eval('(define _test-registry (list))');
-    K.eval('(define _test-suite "")');
-    K.eval('(define push-suite (fn (name) (set! _test-suite name)))');
-    K.eval('(define pop-suite (fn () (set! _test-suite "")))');
-    K.eval(`(define try-call (fn (thunk)
-      (set! _test-registry (append _test-registry (list {:suite _test-suite :thunk thunk})))
-      {:ok true}))`);
-    K.eval(`(define report-pass (fn (name)
-      (let ((i (- (len _test-registry) 1)))
-        (when (>= i 0) (dict-set! (nth _test-registry i) "name" name)))))`);
-    K.eval(`(define report-fail (fn (name error)
-      (let ((i (- (len _test-registry) 1)))
-        (when (>= i 0) (dict-set! (nth _test-registry i) "name" name)))))`);
-    // eval-hs: compile and evaluate a hyperscript expression/command, return its value.
-    // If src contains 'return', use as-is. If it starts with a command keyword (set/put/get),
-    // use as-is (the last expression is the result). Otherwise wrap in 'return'.
-    K.eval(`(define eval-hs (fn (src)
-      (let ((has-cmd (or (string-contains? src "return ")
-                         (string-contains? src "then ")
-                         (= "set " (slice src 0 4))
-                         (= "put " (slice src 0 4))
-                         (= "get " (slice src 0 4)))))
-        (let ((wrapped (if has-cmd src (str "return " src))))
-          (let ((sx (hs-to-sx-from-source wrapped)))
-            (eval-expr sx))))))`);
+    if (window.SxKernel.endModuleLoad) window.SxKernel.endModuleLoad();
   });
 
-  for (const f of TEST_FILES) {
+  if (loadErrors.length > 0) return { loadErrors, results: [] };
+
+  // Define test platform — collects results into an array
+  await page.evaluate(() => {
+    const K = window.SxKernel;
+    K.eval('(define _test-results (list))');
+    K.eval('(define _test-suite "")');
+    // try-call as JS native — catches both SX errors and JS-level crashes.
+    // K.callFn returns null on Eval_error (kernel logs to console.error).
+    // We capture the last console.error to detect failures.
+    K.registerNative('try-call', args => {
+      const thunk = args[0];
+      let lastError = null;
+      const origError = console.error;
+      console.error = function() {
+        const msg = Array.from(arguments).join(' ');
+        if (msg.startsWith('[sx]')) lastError = msg;
+        origError.apply(console, arguments);
+      };
+      try {
+        const r = K.callFn(thunk, []);
+        console.error = origError;
+        if (lastError) {
+          K.eval('(define _tc_err "' + lastError.replace(/\\/g, '\\\\').replace(/"/g, '\\"').slice(0, 200) + '")');
+          return K.eval('{:ok false :error _tc_err}');
+        }
+        return K.eval('{:ok true}');
+      } catch(e) {
+        console.error = origError;
+        const msg = typeof e === 'string' ? e : (e.message || String(e));
+        K.eval('(define _tc_err "' + msg.replace(/\\/g, '\\\\').replace(/"/g, '\\"').slice(0, 200) + '")');
+        return K.eval('{:ok false :error _tc_err}');
+      }
+    });
+    K.eval(`(define report-pass
+      (fn (name) (set! _test-results
+        (append _test-results (list {:suite _test-suite :name name :pass true :error nil})))))`);
+    K.eval(`(define report-fail
+      (fn (name error) (set! _test-results
+        (append _test-results (list {:suite _test-suite :name name :pass false :error error})))))`);
+    K.eval('(define push-suite (fn (name) (set! _test-suite name)))');
+    K.eval('(define pop-suite (fn () (set! _test-suite "")))');
+  });
+
+  // Load test framework + behavioral tests
+  for (const f of ['spec/harness.sx', 'spec/tests/test-framework.sx', 'spec/tests/test-hyperscript-behavioral.sx']) {
+    const src = fs.readFileSync(path.join(PROJECT_ROOT, f), 'utf8');
     const err = await page.evaluate(s => {
-      try { window.SxKernel.load(s); return null; } catch(e) { return e.message; }
-    }, TEST_FILE_CACHE[f]);
-    if (err) loadErrors.push(f + ': ' + err);
+      try { window.SxKernel.load(s); return null; }
+      catch(e) { return 'LOAD ERROR: ' + e.message; }
+    }, src);
+    if (err) {
+      const partial = await page.evaluate(() => window.SxKernel.eval('(len _test-results)'));
+      return { loadErrors: [f + ': ' + err + ' (' + partial + ' results before crash)'], results: [] };
+    }
   }
-  return loadErrors;
+
+  // Collect results — serialize via SX inspect for reliability
+  const resultsRaw = await page.evaluate(() => {
+    const K = window.SxKernel;
+    const count = K.eval('(len _test-results)');
+    const arr = [];
+    for (let i = 0; i < count; i++) {
+      arr.push(K.eval(`(inspect (nth _test-results ${i}))`));
+    }
+    return { count, items: arr };
+  });
+
+  // Parse the SX dict strings
+  const results = resultsRaw.items.map(s => {
+    // s is like '{:suite "hs-add" :name "add class" :pass true :error nil}'
+    const suite = (s.match(/:suite "([^"]*)"/) || [])[1] || '';
+    const name = (s.match(/:name "([^"]*)"/) || [])[1] || '';
+    const pass = s.includes(':pass true');
+    const errorMatch = s.match(/:error "([^"]*)"/);
+    const error = errorMatch ? errorMatch[1] : (s.includes(':error nil') ? null : 'unknown');
+    return { suite, name, pass, error };
+  });
+
+  return { loadErrors, results };
 }
 
-// ===========================================================================
-test.describe('Hyperscript behavioral tests', () => {
-  test.describe.configure({ timeout: 600000 });
 
-  test('upstream conformance', async ({ browser }) => {
-    let page = await browser.newPage();
-    let loadErrors = await bootSandbox(page);
+// ===========================================================================
+// Test suite — one Playwright test per SX test
+// ===========================================================================
+
+test.describe('Hyperscript behavioral tests', () => {
+  test.describe.configure({ timeout: 300000 }); // 5 min for 291 tests
+
+  test('SX behavioral test suite', async ({ browser }) => {
+    const page = await browser.newPage();
+    const { loadErrors, results } = await runSxTests(page);
+    await page.close();
+
     expect(loadErrors).toEqual([]);
 
-    // Get test list
-    const testList = await page.evaluate(() => {
-      const K = window.SxKernel;
-      const count = K.eval('(len _test-registry)');
-      const tests = [];
-      for (let i = 0; i < count; i++) {
-        tests.push({
-          s: K.eval(`(get (nth _test-registry ${i}) "suite")`) || '',
-          n: K.eval(`(get (nth _test-registry ${i}) "name")`) || `test-${i}`,
-        });
-      }
-      return tests;
-    });
-
-    // Run each test individually with timeout
-    const results = [];
-    let consecutiveTimeouts = 0;
-
-    for (let i = 0; i < testList.length; i++) {
-      const t = testList[i];
-
-      // If page is dead (after timeout), reboot
-      if (consecutiveTimeouts > 0) {
-        // After a timeout, the page.evaluate from Promise.race is orphaned.
-        // We must close + reopen to get a clean page.
-        try { await page.close(); } catch(_) {}
-        page = await browser.newPage();
-        loadErrors = await bootSandbox(page);
-        if (loadErrors.length > 0) {
-          for (let j = i; j < testList.length; j++)
-            results.push({ s: testList[j].s, n: testList[j].n, p: false, e: 'reboot failed' });
-          break;
-        }
-        consecutiveTimeouts = 0;
-      }
-
-      let result;
-      try {
-        result = await Promise.race([
-          page.evaluate(async (idx) => {
-            const K = window.SxKernel;
-            const newBody = document.createElement('body');
-            document.documentElement.replaceChild(newBody, document.body);
-
-            const thunk = K.eval(`(get (nth _test-registry ${idx}) "thunk")`);
-            if (!thunk) return { p: false, e: 'no thunk' };
-
-            let lastErr = null;
-            const orig = console.error;
-            console.error = function() {
-              const m = Array.from(arguments).join(' ');
-              if (m.startsWith('[sx]')) lastErr = m;
-              orig.apply(console, arguments);
-            };
-
-            // Drive async suspension chains (wait, fetch, etc.)
-            let pending = 0;
-            const oldDrive = window._driveAsync;
-            window._driveAsync = function driveAsync(result) {
-              if (!result || !result.suspended) return;
-              pending++;
-              const req = result.request;
-              const items = req && (req.items || req);
-              const op = items && items[0];
-              const opName = typeof op === 'string' ? op : (op && op.name) || String(op);
-              const arg = items && items[1];
-              function doResume(val, delay) {
-                setTimeout(() => {
-                  try { const r = result.resume(val); pending--; driveAsync(r); }
-                  catch(e) { pending--; }
-                }, delay);
-              }
-              if (opName === 'io-sleep' || opName === 'wait') doResume(null, Math.min(typeof arg === 'number' ? arg : 0, 10));
-              else if (opName === 'io-fetch') doResume({ok: true, text: ''}, 1);
-              else if (opName === 'io-settle') doResume(null, 5);
-              else if (opName === 'io-wait-event') doResume(null, 5);
-              else pending--;
-            };
-
-            try {
-              const r = K.callFn(thunk, []);
-              // If thunk itself suspended, drive it
-              if (r && r.suspended) window._driveAsync(r);
-              // Wait for all pending async chains to settle
-              if (pending > 0) {
-                await new Promise(resolve => {
-                  let waited = 0;
-                  const check = () => {
-                    if (pending <= 0 || waited > 2000) resolve();
-                    else { waited += 10; setTimeout(check, 10); }
-                  };
-                  setTimeout(check, 10);
-                });
-              }
-              console.error = orig;
-              window._driveAsync = oldDrive;
-              return lastErr ? { p: false, e: lastErr.replace(/[\\"]/g, ' ').slice(0, 150) } : { p: true, e: null };
-            } catch(e) {
-              console.error = orig;
-              window._driveAsync = oldDrive;
-              return { p: false, e: (e.message || '').replace(/[\\"]/g, ' ').slice(0, 150) };
-            }
-          }, i),
-          new Promise(resolve => setTimeout(() => resolve({ p: false, e: 'TIMEOUT' }), 3000))
-        ]);
-      } catch(e) {
-        result = { p: false, e: 'CRASH: ' + (e.message || '').slice(0, 80) };
-      }
-
-      if (result.e === 'TIMEOUT' || (result.e && result.e.startsWith('CRASH'))) {
-        consecutiveTimeouts++;
-      }
-
-      results.push({ s: t.s, n: t.n, p: result.p, e: result.e });
-    }
-
-    try { await page.close(); } catch(_) {}
-
-    // Tally
+    // Tally and report
     let passed = 0, failed = 0;
-    const cats = {};
-    const errTypes = {};
+    const failsByCat = {};
     for (const r of results) {
-      if (r.p) passed++; else {
+      if (r.pass) { passed++; }
+      else {
         failed++;
-        const e = r.e || '';
-        let t = 'other';
-        if (e === 'TIMEOUT') t = 'timeout';
-        else if (e.includes('NOT IMPLEMENTED')) t = 'stub';
-        else if (e.includes('callFn')) t = 'crash';
-        else if (e.includes('Assertion')) t = 'assert-fail';
-        else if (e.includes('Unhandled')) t = 'unhandled';
-        else if (e.includes('Expected')) t = 'wrong-value';
-        else if (e.includes('Cannot read')) t = 'null-ref';
-        else if (e.includes('Undefined')) t = 'undef-sym';
-        else if (e.includes('no thunk')) t = 'no-thunk';
-        else if (e.includes('reboot')) t = 'reboot-fail';
-        if (!errTypes[t]) errTypes[t] = 0;
-        errTypes[t]++;
+        if (!failsByCat[r.suite]) failsByCat[r.suite] = 0;
+        failsByCat[r.suite]++;
       }
-      if (!cats[r.s]) cats[r.s] = { p: 0, f: 0 };
-      if (r.p) cats[r.s].p++; else cats[r.s].f++;
     }
     console.log(`\n  Upstream conformance: ${passed}/${results.length} (${(100*passed/results.length).toFixed(0)}%)`);
+    // Per-category summary
+    const cats = {};
+    for (const r of results) {
+      if (!cats[r.suite]) cats[r.suite] = { p: 0, f: 0 };
+      if (r.pass) cats[r.suite].p++; else cats[r.suite].f++;
+    }
     for (const [cat, s] of Object.entries(cats).sort((a,b) => b[1].p - a[1].p)) {
       const mark = s.f === 0 ? `✓ ${s.p}` : `${s.p}/${s.p+s.f}`;
       console.log(`    ${cat}: ${mark}`);
     }
-    console.log(`  Failure types:`);
-    for (const [t, n] of Object.entries(errTypes).sort((a,b) => b[1] - a[1])) {
-      console.log(`    ${t}: ${n}`);
+
+    // Failure details — classify by error type
+    const errorTypes = {};
+    for (const r of results.filter(r => !r.pass)) {
+      const e = r.error || 'unknown';
+      let type = 'other';
+      if (e.includes('NOT IMPLEMENTED')) type = 'not-generated';
+      else if (e.includes('[sx] callFn')) type = 'callFn-crash';
+      else if (e.includes('Assertion failed')) type = 'assertion';
+      else if (e.includes('Undefined symbol')) type = 'undefined-symbol';
+      else if (e.includes('Expected')) type = 'wrong-value';
+      else if (e.includes('Cannot read')) type = 'null-ref';
+      else if (e.includes('not defined')) type = 'js-undef';
+      if (!errorTypes[type]) errorTypes[type] = [];
+      errorTypes[type].push(`[${r.suite}] ${r.name}: ${e.slice(0, 80)}`);
     }
-    // Show ALL crash errors (deduplicated by error message)
-    const uniqueErrors = {};
-    for (const r of results.filter(r => !r.p)) {
-      const e = (r.e || '').slice(0, 100);
-      if (!uniqueErrors[e]) uniqueErrors[e] = { count: 0, example: r };
-      uniqueErrors[e].count++;
-    }
-    console.log(`  Unique error messages (${Object.keys(uniqueErrors).length}):`);
-    for (const [e, info] of Object.entries(uniqueErrors).sort((a,b) => b[1].count - a[1].count).slice(0, 25)) {
-      console.log(`    [${info.count}x] ${e}`);
-    }
-    // Show ALL failing tests with errors (for diagnosis)
-    const failsByCategory = {};
-    for (const r of results.filter(r => !r.p)) {
-      if (!failsByCategory[r.s]) failsByCategory[r.s] = [];
-      failsByCategory[r.s].push(r);
-    }
-    for (const [cat, fails] of Object.entries(failsByCategory).sort((a,b) => a[0].localeCompare(b[0]))) {
-      for (const f of fails.slice(0, 5)) {
-        console.log(`  FAIL ${f.s}/${f.n}: ${(f.e||'').slice(0, 100)}`);
-      }
+    console.log(`\n  Failure breakdown:`);
+    for (const [type, items] of Object.entries(errorTypes).sort((a,b) => b[1].length - a[1].length)) {
+      console.log(`    ${type}: ${items.length}`);
+      for (const item of items.slice(0, 5)) console.log(`      ${item.slice(0, 200)}`);
+      if (items.length > 3) console.log(`      ...and ${items.length - 3} more`);
     }
 
-    expect(results.length).toBeGreaterThanOrEqual(830);
-    expect(passed).toBeGreaterThanOrEqual(300);
+    // Hard gate — ratchet this up as implementation improves
+    expect(results.length).toBeGreaterThan(0);
+    expect(passed).toBeGreaterThanOrEqual(460);
   });
 });