Degem finds unused gems in the Ruby bundle (ie, an app with a `Gemfile` or a gem with both a `Gemfile` and a gemspec).

Static deprecation analysis tool to keep your code cool

An experimental gem that helps you rewrite deprecated code automatically.

Tool to visualize Ruby class dependencies

Code supporting deployments.

Discodactyl is an experimental toolkit for XRD service discovery documents and related protocols. It includes implementations of XRD URITemplate Link-Patterns, basic site-meta support, HTTP Link header parsing, acct: URIs and a webfinger poking stick.

Syntac Highlighter for Ruby

docrb-parser is responsible for parsing Ruby sources into a structured format for usage by docrb and docrb-html.

An Inngest-style durable workflow runtime built on ActiveJob::Continuable, Active Record, and Rails.event.

Parses ruby to rewrite how locals work

Evilution is a mutation testing tool for Ruby. It validates test suite quality by making small code changes and checking if tests catch them. AI-agent-first design with JSON output, diff-based targeting, and coverage-based filtering.

Use Fastererer to check various places in your code that could be faster. A fork of fasterer (https://github.com/DamirSvrtan/fasterer) with Ruby 4.0 support and native Prism parsing.

Static and observational runtime fiber-scheduler auditor for Ruby and Rails

A HAML to ERB converter for migrating Rails views. Handles tags, attributes, Ruby code, blocks, filters, and interpolation.

Hen'i-tai (変異体) is a mutation testing framework for Ruby 4+. It produces Stryker-compatible mutation-testing-report-schema JSON, integrates with the Stryker Dashboard, and ships with a standalone HTML report powered by mutation-testing-elements. A free, open-source alternative to the mutant gem ...

A tool to generate LSIF and SCIP index files for Ruby codebases

Combines static AST analysis with runtime profiling to prioritize performance optimizations by actual impact

Immosquare-cleaner streamlines Rails applications by running tools like RuboCop, ERBLint, Stylelint and more. It ensures code quality, readability, and consistency across the application.

Import specific constants from a file, into the global namespace or into another constant.

Kaisoku selects impacted Ruby tests with safe fallbacks, dependency maps, parallel execution, and evaluation tooling.