diff --git a/.gitignore b/.gitignore
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+++ b/.gitignore
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+/build*/
+/.venv/
+*.o
+*.pyc
+.DS_Store
diff --git a/docs/JS-ENGINE.md b/docs/JS-ENGINE.md
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+# JS Engine Integration (QuickJS)
+
+- Embed QuickJS for safe, deterministic, sandboxed transforms.
+- No network, no filesystem by default; expose only Kompanion tool FFI shims.
+- Use for text filters, parsers, light data munging; scripts under `~/.config/kompanion/js/`.
+- FFI bridge: `js.callTool(name, args)` → JSON-RPC.