The bytecode compiler emitted OP_CALL_PRIM (52) for every primitive call, even
for arithmetic and comparison hot-paths. The VM had specialized opcodes
(OP_ADD, OP_SUB, OP_EQ, etc.) defined but unused.
- lib/compiler.sx (compile-call): emit specialized 1-byte opcode when the
primitive name + arity matches one of {+, -, *, /, =, <, >, cons, not, len,
first, rest}. Falls back to CALL_PRIM otherwise. fib bytecode: 50 → 38 bytes.
- hosts/ocaml/lib/sx_compiler.ml: mirror change in the auto-generated OCaml
compiler so SXBC export from mcp_tree uses the same emission.
- hosts/ocaml/lib/sx_vm.ml: extend OP_ADD/SUB/MUL/DIV to handle Integer+Integer
(not just Number+Number). Inline OP_EQ via Sx_runtime._fast_eq. Inline
OP_LT/GT mixed-numeric comparisons. Avoids Hashtbl lookup on the fallback
path for the common integer cases that dominate tight loops.
- hosts/ocaml/bin/bench_vm.ml: VM-only benchmark — loads compiler.sx via CEK,
JIT-compiles each fn, measures Sx_vm.call_closure throughput.
Median improvements (best of 3 runs of 9-min, bench_vm.exe):
fib(22) 107.87ms → 33.13ms -69%
loop(200000) 429.64ms → 161.16ms -62%
sum-to(50000) 72.85ms → 36.74ms -50%
count-lt(20000) 28.44ms → 17.58ms -38%
count-eq(20000) 37.23ms → 15.46ms -58%
Tests: 4550/4550 OCaml passing (unchanged). Zero regressions.
Last step in the sx-improvements roadmap — all 14 steps complete.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Added short aliases make-buffer / buffer? / buffer-append! / buffer->string /
buffer-length on both OCaml and JS hosts, sharing the existing StringBuffer
value type. buffer-append! auto-coerces non-strings via inspect.
Rewrote the OCaml host inspect function to walk a single shared Buffer.t
instead of allocating O(n) intermediate strings via String.concat at every
recursion level. inspect underlies sx-serialize and error-path formatting,
so this benefits the tightest serialization paths.
Median improvements (bin/bench_inspect.exe, best-of-3 of 9-run min):
tree-d8 (75KB): 5.31ms -> 1.30ms (-76%)
tree-d10 (679KB): 81.89ms -> 16.02ms (-80%)
dict-1000: 0.80ms -> 0.31ms (-61%)
list-2000: 0.74ms -> 0.33ms (-55%)
Tests: OCaml 4545 -> 4550. JS 2591 -> 2596. Zero regressions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
CEK frames were already records (cek_frame in sx_types.ml), so the actual
hot-path bottleneck was prim_call "=" [...] in step_continue/step_eval
dispatch: each step did a Hashtbl lookup + 2x list cons + pattern match
just to compare frame-type strings.
Added a short-circuit fast path in prim_call (sx_runtime.ml) for the
hot operators: =, <, >, <=, >=, empty?, first, rest, len. These bypass
the primitives Hashtbl entirely and dispatch directly on value shape.
Inlined _fast_eq for scalar/string equality, which dominates frame-type
dispatch comparisons.
Added bin/bench_cek.exe with five tight-loop benchmarks (fib, loop,
map, reduce, let-heavy). Median of 7 runs:
fib(18) 2789ms -> 941ms (-66%)
loop(5000) 2018ms -> 620ms (-69%)
map sq xs(1000) 108ms -> 48ms (-56%)
reduce + ys(2000) 72ms -> 10ms (-86%)
let-heavy(2000) 491ms -> 271ms (-45%)
Tests: 4545/4545 passing baseline preserved (1339 pre-existing failures
unchanged).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Streaming chunked transfer with shell-first suspense and resolve scripts.
Hyperscript parser/compiler/runtime expanded for conformance. WASM static
assets added to OCaml host. Playwright streaming and page-level test suites.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Root cause: _env_bind_hook mirrored ALL env_bind calls (including
lambda parameter bindings) to the shared VM globals table. Factory
functions like make-page-fn that return closures capturing different
values for the same param names (default-name, prefix, suffix) would
have the last call's values overwrite all previous closures' captured
state in globals. OP_GLOBAL_GET reads globals first, so all closures
returned the last factory call's values.
Fix: only sync root-env bindings (parent=None) to VM globals. Lambda
parameter bindings stay in their local env, found via vm_closure_env
fallback in OP_GLOBAL_GET.
Also in this commit:
- OP_CLOSURE propagates parent vm_closure_env to child closures
- Remove JIT globals injection (closure vars found via env chain)
- sx_server.ml: SX-Request header → returns text/sx (aser only)
- sx_server.ml: diagnostic endpoint GET /sx/_debug/{env,eval,route}
- sx_server.ml: page helper stubs for deep page rendering
- sx_server.ml: skip client-libs/ dir (browser-only definitions)
- adapter-html.sx: unknown components → HTML comment (not error)
- sx-platform.js: .sxbc fallback loader for bytecode modules
- Delete sx_http.ml (standalone HTTP server, unused)
- Delete stale .sxbc.json files (arity=0 bug, replaced by .sxbc)
- 7 new closure isolation tests in test-closure-isolation.sx
- mcp_tree.ml: emit arity + upvalue-count in .sxbc.json output
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The home stepper's step-idx signal was not persisting across SX
navigation because set-cookie/freeze-to-sx wasn't working in the
WASM kernel. Replace with def-store which uses a global registry
that survives island re-hydration.
Also fix sx_http.exe build: add sx_http back to dune, inline scope
primitives (Sx_scope module was removed), add declarative form
stubs and render stubs, fix /sx/ home route mapping.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
New comprehension tools:
- sx_find_across: search pattern across all .sx files in a directory
- sx_comp_list: list all definitions (defcomp/defisland/defmacro/defpage/define)
- sx_comp_usage: find all uses of a component across files
- sx_diff: structural diff between two .sx files (ADDED/REMOVED/CHANGED)
- sx_eval: REPL — evaluate SX expressions in the MCP server env
Smart read_tree enhancements:
- Auto-summarise large files (>200 lines)
- focus param: expand only matching subtrees, collapse rest
- max_depth/max_lines/offset for depth limiting and pagination
Smart editing tools:
- sx_rename_symbol: rename all occurrences of a symbol in a file
- sx_replace_by_pattern: find+replace first/all pattern matches
- sx_insert_near: insert before/after a pattern match (top-level)
- sx_rename_across: rename symbol across all .sx files (with dry_run)
- sx_write_file: create .sx files with parse validation
Development tools:
- sx_pretty_print: reformat .sx files with indentation (also used by all edit tools)
- sx_build: build JS bundle or OCaml binary
- sx_test: run test suites with structured pass/fail results
- sx_format_check: lint for empty bindings, missing bodies, duplicate params
- sx_macroexpand: evaluate expressions with a file's macro definitions loaded
Also: updated hook to block Write on .sx files, added custom explore agent.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Phase 1-3 of the SX Tools plan — structural reading, editing, and
MCP server for .sx files.
lib/tree-tools.sx — Pure SX functions for tree comprehension and editing:
Comprehension: annotate-tree, summarise, read-subtree, get-context,
find-all, get-siblings, validate, navigate
Editing: replace-node, insert-child, delete-node, wrap-node, tree-set
Helpers: list-replace, list-insert, list-remove, replace-placeholder
lib/tests/test-tree-tools.sx — 107 tests covering all functions.
hosts/ocaml/bin/mcp_tree.ml — MCP server (stdio JSON-RPC) exposing
11 tools. Loads tree-tools.sx into the OCaml evaluator, parses .sx
files with the native parser, calls SX functions for tree operations.
The MCP server can be configured in Claude Code's settings.json as:
"mcpServers": { "sx-tree": { "command": "path/to/mcp_tree.exe" } }
1429 tests passing (1322 existing + 107 new tree-tools).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
JIT allowlist (sx_server.ml):
- Replace try-every-lambda strategy with StringSet allowlist. Only
functions in the list get JIT compiled (compiler, parser, pure transforms).
Render functions that need dynamic scope skip JIT entirely — no retry
overhead, no silent fallbacks.
- Add (jit-allow name) command for dynamic expansion from Python bridge.
- JIT failures log once with "[jit] DISABLED fn — reason" then go silent.
Standalone --test mode (sx_server.ml):
- New --test flag loads full env (spec + adapters + compiler + signals),
supports --eval and --load flags. Quick kernel testing without Docker.
Example: dune exec bin/sx_server.exe -- --test --eval '(len HTML_TAGS)'
Integration tests (integration_tests.ml):
- New binary exercising the full rendering pipeline: loads spec + adapters
into a server-like env, renders HTML via both native and SX adapter paths.
- 26 tests: HTML tags, special forms (when/if/let), letrec with side
effects, component rendering, eval-expr with HTML tag functions.
- Would have caught the "Undefined symbol: div/lake/init" issues from
the previous commit immediately without Docker.
VM cleanup (sx_vm.ml):
- Remove temporary debug logging (insn counter, call_closure counter,
VmClosure depth tracking) added during debugging.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Eliminated double-aser for HTMX requests: build OOB wrapper AST
(~shared:layout/oob-sx :content wrapped_ast) and aser_slot in ONE
pass — same pattern as the full-page path. Halves aser_slot calls.
Added kernel-side timing to stderr:
[aser-slot] eval=3.6s io_flush=0.0s batched=3 result=22235 chars
Results show batch IO works (io_flush=0.0s for 3 highlight calls)
and the bottleneck is pure CEK evaluation time, not IO.
Performance after single-pass fix:
Home: 0.7s eval (was 2.2s total)
Reactive: 3.6s eval (was 6.8s total)
Language: 1.1s eval (was 18.9s total — double-aser eliminated)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
SX-to-OCaml transpiler (transpiler.sx) generates sx_ref.ml (~90KB, ~135
mutually recursive functions) from the spec evaluator. Foundation tests
all pass: parser, primitives, env operations, type system.
Key design decisions:
- Env variant added to value type for CEK state dict storage
- Continuation carries optional data dict for captured frames
- Dynamic var tracking distinguishes OCaml fn calls from SX value dispatch
- Single let rec...and block for forward references between all defines
- Unused ref pre-declarations eliminated via let-bound name detection
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
