We introduced breaking changes in RubyGems/Bundler 4 in order to improve usability, security, and maintainability of the tool. This document describes the changes that you will find when upgrading to RubyGems 4 and Bundler 4, and how to prepare for them while still using Bundler 2.7. RubyGems 4: CLI behavior changes Removed gem query command Please use gem search or gem list instead.