Ruby Gems

Just a general collection of gems I’ve known and loved (or want to try out).


  • Coditsu will produce a diff between versions of a gem. Great if you want to see what’s changed, or need to do serious auditing of dependencies - run a bundle update, and then hit this for all the changes in Gemfile.lock
  • RailsDiff will produce a diff between the output of rails new, handy for making sure you’re picking up new default configs as you roll the update train.

Code Coverage

  • Debride finds uncalled methods
  • Rcov measures coverage while running tests
  • Coverband measures coverage in production




  • Byebug is my go-to for tracing, to step into function calls, skip to next line, and continue execution.
  • Pry is the other really popular one.
  • Jard looks interesting, provides a multi-window debugger environment, with a GUI stack trace, local variable dumps, threads, etc.
  • Ruby is also getting a native debugger in 3.1 with more interesting breakpoints/callbacks that might prove useful for IDE integration.

Worker Queues

All these queues support ActiveJob in Rails

  • Que leans heavily on Postgres-specific features for queue management, keeps it in the DB
  • Resque is Redis-backed, includes a management site
  • Sidekiq also Redis-backed, includes management site, and includes a Pro paid offering with some additional enterprisey features