vibe

vibe language prototype and runtime (MoonBit).

Features

Language

Type inference with effects (with {Async}, with {Error})
Pattern matching and destructuring
Module system with import/export
Async/await syntax (runtime gate: --unstable-async)
Lambda expressions with placeholder shorthand (_+1)

Runtime Targets

Target	Description
Interpreter (native)	Full-featured runtime with FFI
Interpreter (js)	Browser/Node.js compatible
WASM	Minimal core WASM output
WASM + js-string	WASM with JS string builtins
Component Model	WASM Component for composition

Builtin Functions

Function	Interpreter	WASM	Description
`sleep(ms)`	native only	host runtime	Sleep for milliseconds
`sh(cmd)`	native only	host import	Execute shell command
`path(str)`	native only	host import	Normalize path
`Stdout::write_char(code)`	effect trace	`wasi:cli/stdout` + `wasi:io/streams` import	Write one char code to stdout
`Stdout::write_stream(text)`	effect trace	`wasi:cli/stdout` + `wasi:io/streams` import	Write a string chunk to stdout
`Stdin::read_char()`	returns `-1` on eof	`wasi:cli/stdin` + `wasi:io/streams` import	Read one char code from stdin
`Stdin::read_stream(max)`	returns `\"\"` on eof/error	`wasi:cli/stdin` + `wasi:io/streams` import	Read up to `max` bytes as a string chunk
`await expr`	interpreter	stack-switching (x86_64)	Async operation

Development

just              # check + test
just fmt          # format code
just check        # type check
just test         # run tests
just test-integration-deno  # deno integration tests (artifact-only wasm-gc)
just coverage     # moonbit + wasm(deno) coverage
just coverage-moon  # moonbit source coverage (summary/cobertura/html)
just coverage-deno  # wasm integration coverage (summary/lcov/html)
just coverage-wasm-source examples/pattern_coverage.vibe  # vibe source span + wasm counter coverage
just coverage-wasm-std  # vibe/prelude *_test.vibe coverage aggregation (wasm source)
just release-check  # full check before release

Coverage で使う主な環境変数:

VIBE_MOON_COVERAGE_TARGET=native|wasm|wasm-gc|js
VIBE_MOON_COVERAGE_PACKAGE=<pkg>
VIBE_MOON_COVERAGE_MIN_LINE=<percent>
VIBE_DENO_COVERAGE_FILTER=<regex>
VIBE_DENO_COVERAGE_MIN_LINE=<percent>
VIBE_WASM_SOURCE_COVERAGE_MODE=wasm|wasm-js-string
VIBE_WASM_SOURCE_COVERAGE_NO_DCE=0|1
VIBE_WASM_SOURCE_COVERAGE_RUN_TESTS=0|1
VIBE_WASM_SOURCE_COVERAGE_DIR=<dir>
VIBE_WASM_STD_COVERAGE_MODE=wasm|wasm-js-string
VIBE_WASM_STD_COVERAGE_FILTER=<regex>
VIBE_WASM_STD_COVERAGE_EXCLUDE=<regex>
VIBE_WASM_STD_COVERAGE_STRICT=0|1
VIBE_WASM_STD_COVERAGE_DIR=<dir>

WASM 向けは 3 層で測る:

MoonBit 本体ロジック: just coverage-moon（必要なら VIBE_MOON_COVERAGE_TARGET=wasm-gc）
WebAssembly.instantiate 経由の統合導線: just coverage-deno
vibe ソース span ベースの line/branch: just coverage-wasm-source <entry.vibe>
vibe/prelude の集計: just coverage-wasm-std（summary の cases(total/success) と failures.txt を確認）
詳細: docs/coverage.md

js/vibe/ には wasm 成果物 (src/lib) を呼ぶ JS バインディングを置く:

js/vibe/index.js / js/vibe/index.d.ts (createVibeService, init, check, format, checkProject, ideOutline, idePeekDef, ideSearch)
- createVibeService({ bootstrap: { prelude, kv } }) または service.init({ prelude, kv }) で初期状態を注入可能
- checkProject({ entry, files }) と IDE request ({ entry, path, files, ... }) は import 解決対応（init で注入した kv も解決対象）
js/vibe/cli.js shell から使う JS CLI (vibe ide 相当)
js/vibe/lsp.js / js/vibe/lsp.d.ts (stdio/ws 非依存の transport 抽象)

wasm/vibe/ には src/lib の配布用 wasm (wasm-gc) を置く:

wasm/vibe/vibe.wasm
just build-wasm-vibe で更新
just test-wasm-vibe-wasmtime で wasmtime --invoke vibe_check 疎通確認

CLI

# Run vibe script
just run run examples/basics.vibe
# (comprehensive syntax tour)
just run run examples/syntax.vibe

# Run unstable async examples (required for await/sleep/yield runtime execution)
just run run --unstable-async examples/async.vibe
# flags can also be placed before command
just run --unstable-async run examples/async.vibe
# unstable threads probe builtin (via line repl)
printf 'Threads::probe_wat()\nexit\n' | just run repl-stdin --no-prompt --unstable-threads
# unstable threads runtime hints (recommended -W/-S flags)
printf 'Threads::runtime_hints()\nexit\n' | just run repl-stdin --no-prompt --unstable-threads

# Run tests in script
just run test examples/*.vibe
# For async tests
just run test --unstable-async examples/async.vibe

# Compile to WASM
just run compile --wasm examples/wasm/sleep_demo.vibe -o /tmp/out.wasm
# Compile + optimize with wite (-Oz default)
just run compile --wasm --wite examples/wasm/sleep_demo.vibe -o /tmp/out.opt.wasm
# Compile + optimize with explicit level
just run compile --component -O3 script.vibe -o out.component.opt.wasm

# Compile to Component Model WASM
just run compile --component script.vibe -o out.component.wasm

# Generate component embedding WIT for wasm-tools/wkg pipeline
just run compile --wit-component script.vibe -o out.component.wit

# Build validated component via wkg + wasm-tools
just component-wkg script.vibe
# (stdio builtins are wired through wasi:cli/stdin|stdout + wasi:io/streams)

# Interactive REPL
just run repl

# Line REPL for stdio/wasi-like environments
just run repl-wasi --no-prompt
# Enable unstable async in REPL
just run repl-wasi --unstable-async

# IDE-like symbol queries
just run ide outline examples/syntax.vibe
just run ide peek-def some_fn examples/syntax.vibe
just run ide search Option examples/syntax.vibe
# JS-backed ide command
just ide-js outline examples/syntax.vibe
just ide-js peek-def some_fn examples/syntax.vibe
just ide-js search Option examples/syntax.vibe
# `ide-js` は entry から相対 import を再帰収集して project request を生成する

# Advanced graph index PoC (build/query/verify)
just run index build examples/syntax.vibe -o /tmp/advanced-graph-index.json
just run index query symbol add /tmp/advanced-graph-index.json
just run index verify /tmp/advanced-graph-index.json

# Emit LSIF from the same symbol index backend
just run lsif -o /tmp/vibe.lsif examples/syntax.vibe

# Build wasm line REPL (preview2 stdio imports)
just build-repl-wasi-wasm
# Build wasm compiler CLI (wasi)
just build-compiler-wasi-wasm
# Build wasm checker CLI (json diagnostics)
just build-checker-wasi-wasm
# Run wasm compiler CLI (`--wasm` は wasm-gc を優先)
printf '1 + 2\n' > /tmp/gc_demo.vibe
just run-compiler-wasi-wasm --wasm /tmp/gc_demo.vibe -o /tmp/out.wasm
# Run wasm checker CLI (file path or --source)
just run-checker-wasi-wasm /tmp/gc_demo.vibe
just run-checker-wasi-wasm --source '1 + true'
# Run wasm formatter mode (vibe fmt 相当)
just run-checker-wasi-wasm --format --source 'let  x=1'
# Same as above (shortcut)
just run-compiler-wasi-wasm-gc /tmp/gc_demo.vibe -o /tmp/out.wasm
# Use core wasm MVP backend explicitly
just run-compiler-wasi-wasm-mvp examples/basics.vibe -o /tmp/out.mvp.wasm

# Build component + run with wasmtime (explicit invoke for non-command component)
just component-run vibe/prelude/test_import.vibe
# stdin 経由の実行も可能:
printf 'A' | just component-run your_stdio_script.vibe
# stream TUI デモ:
printf 'hello\nworld\n' | just component-run examples/wasm/tui_stream_demo.vibe
# 簡易デモ実行タスク:
just demo-tui-stream

# moonix で実行（moonix の CLI 差分はランチャで吸収）
just component-run-moonix vibe/prelude/test_import.vibe
# moonix バイナリが無い場合の手動 bootstrap
just bootstrap-moonix

# Install CLI to ~/.local/bin/vibe
just install

build-repl-wasi-wasm output:

_build/wasm/release/build/vibe_wasi/vibe_wasi.wasm
this binary imports wasi:cli/stdin|stdout@0.2.0 and wasi:io/streams@0.2.0 directly
run it with a component/p3-compatible host (for example moon-component/mwac integration), not moon run --target wasm
for script-level stdio execution, use just component-run <file.vibe>
moonix 実行は just component-run-moonix <file.vibe>（必要なら MOONIX_BIN=/path/to/moonix）
component-run-moonix は moonix 未導入時に scripts/bootstrap_moonix_bin.sh を自動試行

build-compiler-wasi-wasm output:

_build/wasm/release/build/cmd/vibe_compile_wasi/vibe_compile_wasi.wasm
run with moon run --target wasm src/cmd/vibe_compile_wasi -- ... (or just run-compiler-wasi-wasm ...)
compiler filesystem access is routed through src/io.FileSystemAdapter abstraction
vibe_compile_wasi では --wasm が wasm-gc を選ぶ（MVP を使う場合は --wasm-mvp）
現状 wasm-gc backend は実験段階のため、複雑な文法は --wasm-mvp を使う

WASM Execution

With async host runtime (supports sleep)

# Build Rust host runtime
just build-async-host

# Run sleep demo
just sleep-demo

# Run any WASM with sleep support
just run compile --wasm your_script.vibe -o /tmp/out.wasm
just run-wasm-async /tmp/out.wasm

With wasmtime (basic)

just run compile --wasm script.vibe -o /tmp/out.wasm
wasmtime /tmp/out.wasm

With `deps/wasmtime` submodule (experimental flags)

# one-time init + build
just wasmtime-submodule-init
just build-wasmtime-submodule

# run wasmtime from submodule directly
just wasmtime-submodule run -W gc --invoke run /tmp/out.wasm

# or switch existing vibe scripts/tasks to submodule wasmtime
VIBE_USE_WASMTIME_SUBMODULE=1 just component-run script.vibe
VIBE_USE_WASMTIME_SUBMODULE=1 just bench-wasmtime

# inject extra wasmtime runtime flags into vibe scripts/*
# (space-separated list; each token is passed as -W / -S)
VIBE_WASMTIME_WASM_FLAGS='component-model-async=y concurrency-support=y' \
VIBE_WASMTIME_WASI_FLAGS='p3=y' \
VIBE_USE_WASMTIME_SUBMODULE=1 \
just component-run script.vibe

# flags are also propagated through justfile-backed tasks
VIBE_WASMTIME_WASM_FLAGS='gc=y' just bench-wasmtime

# inspect current flag env values used by scripts/wasmtime_run.sh
just show-wasmtime-flags

# run minimal WASI Threads probe (imports wasi::thread-spawn + env::memory)
# defaults to:
#   VIBE_WASMTIME_WASM_FLAGS='threads=y shared-memory=y'
#   VIBE_WASMTIME_WASI_FLAGS='threads=y'
VIBE_USE_WASMTIME_SUBMODULE=1 just experimental_wasi_threads_probe

# direct runner under x/threads
VIBE_USE_WASMTIME_SUBMODULE=1 src/x/threads/run_probe.sh

With wasmtime stack-switching (x86_64 Linux only)

# Via container (for stack-switching support)
just experimental_wasmtime_stack_switching /tmp/out.wasm

Project Structure

src/
├── backend/        # Runtime host adapters (target-specific sleep, etc.)
├── codebase/       # Nix-like content-addressed store and path mappings
├── io/             # Unified IO boundary (fs/env/shell/sleep facade)
├── loader/         # Source/lock resolution and module loading pipeline
├── core/           # AST types and serialization
├── parser/         # Lexer and parser
├── checker/        # Type checker with effects
├── codegen/        # WASM code generation
├── runtime/        # Interpreter and compilation
├── x/fp/           # Floating-point to decimal formatter utilities
├── x/module_graph/ # Experimental module graph index and codecs
├── cmd/vibe/       # CLI command implementation (native/js)
├── cmd/vibe_wasi/  # WASI line-REPL command (wasm)
└── tests/          # Integration-like blackbox tests

examples/
├── *.vibe           # Example scripts (interpreter)
└── wasm/           # WASM-only examples (require host)

vibe/
└── prelude/        # vibe core library (self-hosted prelude modules)

examples/async_host/  # Rust/wasmtime host runtime

Docs

docs/vibe.md - Language specification (normative for implemented behavior)
docs/module_design.md - Module design proposals (non-normative)
docs/module-system.md - Current module system spec
docs/vibe-eval.md - Eval workflow documentation
docs/async_design.md - Async design proposals (non-normative)
docs/unstable_features.md - Unstable runtime feature flags (--unstable-async, --unstable-threads)
docs/coverage.md - Coverage strategy for MoonBit + WASM integration

Fixtures

Fixtures live in fixtures/*.vibe and include a __DATA__ JSON section.
moon test runs them via src/tests/fixture_test.mbt.

WASM fixtures live in fixtures/wasm/*.vibe and compare expected WAT.
WASM GC fixtures live in fixtures/wasm_gc/*.vibe and check for struct.new/get/set.

Bench

just bench-wasmtime
just bench-compare
just bench-kpi
just bench-kpi bench/kpi_bench.vibe
just bench-std-baseline-update
just run bench examples/simple_bench.vibe
just bench-cmd-latency
just bench-scratch-workflow
just bench-symbol-index
just bench-advanced-graph
just bench-typechecker

vibe bench は bench {} ブロックを言語機能として実行する。
<file|dir...> 指定時は --backend wasm がデフォルト（--backend interpreter で従来実装）。
legacy の式ベンチ (--expr/--case/--cases) は interpreter backend のみ対応。
--backend wasm ではサイズ優先で --no-dce -Oz 相当のコンパイルを使い、各ケースに wasm_bytes=<size> を出力する。
just bench-kpi は vibe bench の結果を dist/bench_kpi/latest.tsv に保存し、per_us と wasm_bytes を同時に確認できる。
KPI しきい値は VIBE_BENCH_KPI_MAX_PER_US / VIBE_BENCH_KPI_MAX_WASM_BYTES / VIBE_BENCH_KPI_MAX_SCORE で設定可能。
引数なしの just bench-kpi は bench/kpi_bench.vibe（数値パイプライン/状態更新の4ケース）を対象にする。
VIBE_BENCH_KPI_N / VIBE_BENCH_KPI_WARMUP 未指定時は wasm=20000/1000, interpreter=2000/200 を使う。
just bench-std-baseline-update は vibe/prelude を含む bundle-size budget
(bench/golden/bundle_size_budget.tsv) と KPI snapshot
(bench/golden/kpi_wasm.tsv, bench/golden/kpi_interpreter.tsv) を更新する。

bench-scratch-workflow は scratch 開発フローを段階別に計測する。

VIBE_BENCH_SCENARIOS=all|eval|finalize|export_apply|full (all は , 区切り指定可)
VIBE_BENCH_CHAIN=<N> 定義チェーン長（デフォルト 40）
VIBE_BENCH_WARMUP=<N> / VIBE_BENCH_RUNS=<N>
VIBE_BENCH_EXPORT_JSON=<path> で hyperfine の JSON を保存

License

MIT

mizchi/vibe-lang

vibe

Features

Language

Runtime Targets

Builtin Functions

Development

CLI

WASM Execution

With async host runtime (supports sleep)

With wasmtime (basic)

With `deps/wasmtime` submodule (experimental flags)

With wasmtime stack-switching (x86_64 Linux only)

Project Structure

Docs

Fixtures

Bench

License

On this page

Languages

Contributors

mizchi/vibe-lang

vibe

Features

Language

Runtime Targets

Builtin Functions

Development

CLI

WASM Execution

With async host runtime (supports sleep)

With wasmtime (basic)

With deps/wasmtime submodule (experimental flags)

With wasmtime stack-switching (x86_64 Linux only)

Project Structure

Docs

Fixtures

Bench

License

On this page

Languages

Contributors

With `deps/wasmtime` submodule (experimental flags)