madbomber/ruby-resource-map

Ruby Knowledge

Authoritative resource map for Ruby development. Use these sources rather than searching broadly.

Never use these sources:

• ruby-doc.org
• apidock.com

Official Documentation

Primary source: https://docs.ruby-lang.org/en/

Other Useful Resources

• https://rubyreferences.github.io/rubychanges/ - Version-by-version changelog with examples
• https://railsatscale.com/ - Shopify engineering blog (Latest updates on Ruby and its toolings)

Core & Standard Library

| Term | Meaning | | ---- | ------- | | Default gem | Ships with Ruby, cannot uninstall | | Bundled gem | Ships with Ruby, can uninstall/replace | | Standard library | Part of Ruby itself, not a gem |

| Version | Documentation | Standard Library | | ------- | ------------- | ---------------- | | 3.2 | https://docs.ruby-lang.org/en/3.2/ | https://docs.ruby-lang.org/en/3.2/standard_library_rdoc.html | | 3.3 | https://docs.ruby-lang.org/en/3.3/ | https://docs.ruby-lang.org/en/3.3/standard_library_rdoc.html | | 3.4 | https://docs.ruby-lang.org/en/3.4/ | https://docs.ruby-lang.org/en/3.4/standard_library_md.html | | 4.0 | https://docs.ruby-lang.org/en/4.0/ | https://docs.ruby-lang.org/en/4.0/standard_library_md.html | | master | https://docs.ruby-lang.org/en/master/ | https://docs.ruby-lang.org/en/master/standard_library_md.html |

Typing Ecosystem

Two type definition formats exist in Ruby:

• RBI - Sorbet's format. Uses Ruby DSL syntax (sig { ... }) in .rb and .rbi files.
• RBS - Official Ruby format (Ruby 3.0+). Dedicated syntax in .rbs files or inline as comments.

Sorbet Ecosystem

Sorbet is a static and runtime type checker for Ruby, maintained by Stripe. Key companion tools:

• Tapioca - Generates RBI files for gems and DSLs (Rails, ActiveRecord, etc.)
• Spoom - Coverage analysis, strictness bumping, dead code detection, signature migration

RBS Ecosystem

• rbs - Official CLI for working with RBS files (prototype, list, methods)
• Steep - Type checker that uses RBS

RBS Inline Comments

Sorbet supports RBS-style inline type annotations using #: comment syntax. This eliminates the need for separate .rbi files or verbose sig blocks.

Docs: https://sorbet.org/docs/rbs-comments