# boa-dev/boa

Boa is an embeddable Javascript engine written in Rust.

Repository: https://github.com/boa-dev/boa
Canonical: https://ross.abutalabs.com/products/boa
Language: Rust
License: MIT
License Family: permissive
Topics: rust, javascript-engine, interpreter, javascript-interpreter, ecmascript, hacktoberfest, javascript, parser, wasm, webassembly, rust-crate, runtime
Last push: 2026-08-22T08:07:23+00:00

## Health v2 (maintenance only)
Score: 83/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 53, longevity 100
- inputs: {"age_days": 2947, "days_push": 11, "days_rel": 157, "gap_med": 158, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 7501, forks 655 (observed 2026-08-28T04:10:00.344666+00:00)

## What it is
Boa is an embeddable JavaScript engine (lexer, parser, and interpreter) written in Rust with support for over 90% of the latest ECMAScript specification. It ships as a set of Rust crates including boa_engine, boa_parser, and boa_cli, and can be compiled to WebAssembly.

## Use cases
- embed a JavaScript scripting engine in a Rust application
- run untrusted JS sandboxed inside Rust
- parse and evaluate ECMAScript code programmatically
- compile a JS engine to WebAssembly for the browser
- experiment with JavaScript language implementation in Rust
- use a JS REPL from the command line

## When to choose
- you need to embed a JS engine in Rust without a C dependency like V8
- you want a lightweight, pure-Rust ECMAScript interpreter
- you need a JS engine that compiles to WebAssembly
- you're building tooling that must parse or evaluate JavaScript

## When to avoid
- you need 100% ECMAScript conformance or top-tier JIT performance
- you need full Node.js APIs and ecosystem compatibility
- you're building a production browser or high-throughput server runtime

## Facets
- artifact type: library
- maturity: active
- function: interpreter, parser, compiler
- domain: programming-languages, parsers, developer-tools
- platform: rust, wasm, cli, cross-platform
- tags: javascript-engine, ecmascript, embeddable, lexer, runtime, garbage-collector

## Member repositories
- boa-dev/boa (main) score 83

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:00.344666+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:37:32.055788+00:00, confidence not recorded.
  - readme: https://github.com/boa-dev/boa (fetched 2026-08-28T04:10:00.344666+00:00, sha d1cbd4cc1d79)
  - registry_crates: https://crates.io/api/v1/crates/boa (fetched 2026-08-29T08:32:41.674333+00:00, sha 1da3d3ff855b)
- Data as of 2026-08-30T08:39:29.467469+00:00.