Static analysis tools for Ruby

• Codeac, Code Quality CI Tool
• heckle
• seattlerb/flay: Flay analyzes code for structural similarities. Differences in literal values, variable, class, method names, whitespace, programming style, braces vs do/end, etc are all ignored.
• soutaro/querly: Query Method Calls from Ruby Programs
• apiology/quality: Quality is a tool that runs quality checks on your code using community tools, and makes sure your numbers don’t get any worse over time. Just add ‘rake quality’ as part of your Continuous Integration.
• codegram/pelusa: Static analysis Lint-type tool to improve your OO Ruby code
• Railroader
• Yorick Peterse / ruby-lint
• whitesmith/rubycritic: A Ruby code quality reporter
• makaroni4/sandi_meter: Static analysis tool for checking Ruby code for Sandi Metz’ rules.

I’ve used some of these, but not all. If you have experience with any of them, please leave a comment.