4. Asset fingerprintAsset Fingerprint Plugin for Ruby on Rails - allows you to use md5 or timestamps in query string or in asset filenames as suggested by Google Page Speed
5. Rails Security Checklist🔑 Community-driven Rails Security Checklist (see our GitHub Issues for the newest checks that aren't yet in the README)
6. Real World RailsReal World Rails applications and their open source codebases for developers to learn from
7. awesome-challengesSharpen skills & prepare for interview. Includes puzzles, kata, algorithm & data structure exercises
9. monitorstxtmonitors.txt - lazy web app monitoring, see http://monitorstxt.org and http://monitorstxt.org/monitors.txt
10. spree-single-product-urlsExtension for Spree to give each product a single URL to minimize duplicate content issues. Behaves like Amazon's "Look for similar items in these categories" product page section.
11. rails-code-reviewAn evolving set of guidelines & supporting reasons to consider when code reviewing Ruby on Rails apps