RuboCop is a Ruby code style checking and code formatting tool. It aims to enforce the community-driven Ruby Style Guide.

RuboCop's Node and NodePattern classes.

Dependabot-Common provides the shared code used across Dependabot. If you want support for multiple package managers, you probably want the meta-gem dependabot-omnibus.

Reek is a tool that examines Ruby classes, modules and methods and reports any code smells it finds.

Suspenders is a base Rails project that you can upgrade. It is used by thoughtbot to get a jump start on a working app. Use Suspenders if you're in a rush to build something amazing; don't use it if you like missing deadlines.

Opal is a Ruby to JavaScript compiler. It is source-to-source, making it fast as a runtime. Opal includes a compiler (which can be run in any browser), a corelib and runtime implementation. The corelib/runtime is also very small.

Generate equivalent source for parser gem AST nodes

RubyCritic is a tool that wraps around various static analysis gems to provide a quality report of your Ruby code.

i18n-tasks helps you find and manage missing and unused translations. It analyses code statically for key usages, such as `I18n.t('some.key')`, in order to report keys that are missing or unused, pre-fill missing keys (optionally from Google Translate), and remove unused keys.

IDE tools for code completion, inline documentation, and static analysis

Add #to_ast method to Proc. #to_ast converts Proc object to AST::Node.

Mutation Testing for Ruby.

Sets package level boundaries between a specified set of ruby constants to minimize cross-boundary referencing and dependency.

Better HTML for Rails. Provides sane html helpers that make it easier to do the right thing.

Monitors Ruby apps and reports detailed metrics on performance to Scout.

Provides simple way to integrate regression test selection approach to your RSpec test suite

Gradual Typing for Ruby

ERB Linter tool.

Set of tools to make Sorbet work with Rails seamlessly.

Records the results of every line of code in your file (intended to be like xmpfilter), inspired by Bret Victor's JavaScript example in his talk "Inventing on Principle"