# ruby/prism

Prism Ruby parser

Repository: https://github.com/ruby/prism
Canonical: https://ross.abutalabs.com/products/ruby-prism
Homepage: https://ruby.github.io/prism/
Language: C
License: MIT
License Family: permissive
Last push: 2026-08-25T13:14:43+00:00

## Health v2 (maintenance only)
Score: 91/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 75, longevity 100
- inputs: {"age_days": 1444, "days_push": 8, "days_rel": 169, "gap_med": 25, "n_releases_24m": 12}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1027, forks 191 (observed 2026-08-28T04:03:16.943202+00:00)

## What it is
Prism is a portable, error-tolerant parser for the Ruby programming language written in dependency-free C99. It provides a shared library (libprism) with bindings for Ruby, Rust, Java, and JavaScript/WASM, and is bundled with CRuby 3.3+.

## Use cases
- parse Ruby source code into an AST
- build Ruby linters or static analysis tools
- lex and tokenize Ruby files
- run a Ruby parser in the browser via WASM
- parse Ruby code from Rust or Java
- handle syntax errors gracefully in Ruby tooling

## When to choose
- you need a fast, dependency-free Ruby parser
- you're building developer tooling for Ruby (linters, formatters, analyzers)
- you need error-tolerant parsing of incomplete or invalid Ruby code
- you need Ruby parsing in a non-Ruby language or in the browser

## When to avoid
- you need a full Ruby interpreter or runtime, not just a parser
- you're on CRuby < 3.3 and can't install gems
- you need to evaluate or execute Ruby code

## Facets
- artifact type: library
- maturity: stable
- function: parser, compiler, developer-tools, cli, serialization
- domain: programming-languages, parsers, developer-tools
- platform: c, ruby, rust, jvm, wasm, cross-platform, cli
- tags: ruby-parser, ast, lexer, error-tolerant, c99, language-tooling, syntax-tree, command-line

## Member repositories
- ruby/prism (main) score 91

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:16.943202+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 2026-08-30T07:07:54.673995+00:00, confidence not recorded.
  - readme: https://github.com/ruby/prism (fetched 2026-08-28T04:03:16.943202+00:00, sha ea21a507b3dd)
  - homepage: https://ruby.github.io/prism/ (fetched 2026-08-29T13:08:00.080105+00:00, sha fc72adeaac37)
- Data as of 2026-08-30T08:39:29.467469+00:00.