Ruby Upgrade | Agent Skills Atlas

About this skill

Use when upgrading the Ruby interpreter version of a Bundler/Rails app — especially "upgrade to Ruby 4", "bump Ruby to 4.0", "audit Ruby 4 compatibility", "what breaks on Ruby 4", or a specific target like "Ruby 4.0.5". Triggers on Ruby-major risk symptoms: CGI.parse/CGI::Cookie removal, Net::HTTP implicit Content-Type dropped, demoted default gems (ostruct/logger/benchmark/irb), SortedSet, Setinspect changes, native-extension recompile crashes, openssl 4 pins, and error-tracker fingerprint drift. Also fires on ".ruby-version bump" and "ruby major upgrade". For Rails framework version bumps (6.x/7.x/8.x, config.loaddefaults) use the rails-upgrade skill instead.

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Automated security scan: Partial

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0 potential findings · Scanned 11/4/2026 · Scanner 0.2.1

Content SHA-256: 939ee368126194fd11358a958cd8cce9f9dd60e71497e3ff66238683b0a1c58f

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Original listing metadata

Original name

ruby-upgrade

Original description

Use when upgrading the Ruby interpreter version of a Bundler/Rails app — especially "upgrade to Ruby 4", "bump Ruby to 4.0", "audit Ruby 4 compatibility", "what breaks on Ruby 4", or a specific target like "Ruby 4.0.5". Triggers on Ruby-major risk symptoms: CGI.parse/CGI::Cookie removal, Net::HTTP implicit Content-Type dropped, demoted default gems (ostruct/logger/benchmark/irb), SortedSet, Set#inspect changes, native-extension recompile crashes, openssl 4 pins, and error-tracker fingerprint drift. Also fires on ".ruby-version bump" and "ruby major upgrade". For Rails framework version bumps (6.x/7.x/8.x, config.load_defaults) use the rails-upgrade skill instead.

About this listing

Category: Engineering
Reported license: MIT
Listing language (estimated): English
Review status: Not individually reviewed
Agent compatibility: Atlas installation supports Claude Code, Codex, and Cursor. Skill-specific dependencies and features are checked during setup.