@lute-lang/runtime

The Lute runtime for TypeScript hosts, in Effect 4: load a bundle compiled by lute compile --all, drive the resumable step function, query the state (view, evaluate, def, gate, candidates, …), and replay input logs, on Bun and in browsers.

bun add @lute-lang/runtime [email protected] @effect/[email protected] @effect/[email protected]
# For a local pack, use the runtime tarball path printed by scripts/pack-local.sh:
# bun add @lute-lang/runtime@file:/path/to/lute-lang-runtime-<version>.tgz [email protected] @effect/[email protected] @effect/[email protected]
# or use the dependencies and overrides printed by scripts/pack-local.sh.
# or, for a browser application:
bun add @lute-lang/runtime [email protected] @effect/[email protected]

The host guide — sessions, the Program API, errors, state interchangeability, replay, and local dogfooding with packed tarballs — is docs/runtime/typescript-runtime.md.

Building from the repository

The package wraps the wasm binding of crates/lute-runtime-wasm. In packages/runtime:

bun install
bun run wasm:build      # debug binding -> src/wasm/
bun run build           # dist/: ESM entry points, declarations, the binding
bun run typecheck
bun run test            # builds the binding first (incremental)

bun run wasm:build:release builds the release binding and optimizes it with wasm-opt -O; a published package ships that one.

Tools

wasm:build needs Rust with the wasm32-unknown-unknown target and wasm-bindgen 0.2.126 — exactly the binding crate's wasm-bindgen version. The script resolves it in this order:

1. $WASM_BINDGEN, a path to the binary;
2. wasm-bindgen on PATH;
3. the wasm-pack cache entry of the pinned version, <cache>/.wasm-pack/wasm-bindgen-cargo-install-0.2.126/wasm-bindgen (wasm-bindgen.exe on Windows), where <cache> is ~/Library/Caches on macOS, $XDG_CACHE_HOME or ~/.cache on Linux, and %LOCALAPPDATA% on Windows — wasm-pack leaves it there after any build of a crate pinned to that version.

When none resolves, or the binary cannot be run or reports another version, the script prints

wasm-build: need wasm-bindgen 0.2.126 (set WASM_BINDGEN, put it on PATH, or cargo install --locked wasm-bindgen-cli --version 0.2.126)

and exits 1. Install it with cargo install --locked wasm-bindgen-cli --version 0.2.126.

wasm:build:release also needs binaryen's wasm-opt, from $WASM_OPT or PATH.

The contract schemas under src/generated/ are generated from the Rust types: bun run contract:gen regenerates them and bun run contract:check fails on drift. Never edit them by hand.