![5 Friday links # 20](/media/W1siZiIsImJsb2dfcG9zdHMvMTQzODMzNTA1NC5qcGVnIl0sWyJwIiwidGh1bWIiLCI3NzB4NDAwIyJdXQ/friday_links.jpg?sha=dfe2ca5f58cb1761)
- The Complete Guide to Rails Caching. Speed Up Your Rails App by 66%.
- System Browser Client. A Ruby code browser
- activerecord-import. Extraction of the ActiveRecord::Base#import functionality from ar-extensions for Rails 3 and beyond
- Why you should never, ever, ever use MongoDB
- The Best of RailsConf 2015