# ghcjs/ghcjs

Haskell to JavaScript compiler, based on GHC

Repository: https://github.com/ghcjs/ghcjs
Canonical: https://ross.abutalabs.com/products/ghcjs
Language: Haskell
License: MIT
License Family: permissive
Last push: 2023-01-21T23:46:36+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 5858, "days_push": 1320, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2617, forks 185 (observed 2026-08-28T04:07:04.691946+00:00)

## What it is
GHCJS is a Haskell to JavaScript compiler built on the GHC API, compiling Haskell programs and packages to run in browsers and Node.js. It includes a JavaScript code generator and a customized variant of the GHC library, with boot libraries compiled via an emscripten toolchain.

## Use cases
- compile haskell code to javascript
- run haskell programs in the browser
- build frontend web apps in haskell
- target nodejs from haskell
- reuse existing haskell libraries for web development

## When to choose
- you want to write web or node.js applications in Haskell
- you need to reuse existing Haskell packages in a JavaScript environment
- you want GHC-compatible type checking and semantics for code compiled to JS

## When to avoid
- you need a simple, actively maintained Haskell-to-JS pipeline without GHC version constraints
- you want to call C foreign libraries directly from compiled code
- your project requires the latest GHC features or fast release cadence

## Facets
- artifact type: cli-tool
- maturity: maintenance
- function: compiler, programming-language
- domain: compilers, programming-languages, web-development
- platform: cross-platform, cli
- tags: haskell, javascript, ghc, transpiler, emscripten, compiler, nodejs

## Member repositories
- ghcjs/ghcjs (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:04.691946+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 2026-08-30T08:31:47.578361+00:00, confidence not recorded.
  - readme: https://github.com/ghcjs/ghcjs (fetched 2026-08-28T04:07:04.691946+00:00, sha 25e22cea86ba)
- Data as of 2026-08-30T08:39:29.467469+00:00.