Ruby applications now receive exact bundler version

Change effective on 09 January 2026

The exact bundler version from the Gemfile.lock is now installed without conversion.

If your application fails after this change, you can manually adjust your BUNDLED WITH value in the Gemfile.lock to match the previously used exact version:

  • BUNDLED WITH 1.x. installs bundler 1.17.3
  • BUNDLED WITH 2.0.x to 2.3.x installs bundler 2.3.25
  • BUNDLED WITH 2.4.x installs bundler 2.4.22
  • BUNDLED WITH 2.5.x installs bundler 2.5.23
  • BUNDLED WITH 2.6.x installs bundler 2.6.9
  • BUNDLED WITH 2.7.x installs bundler 2.7.2
  • BUNDLED WITH 4.0.x installs bundler 4.0.0

For example, if your application started failing, using bundler 2.6.1, you could adjust it to instead use the 2.6.x series above which would be:

BUNDLED WITH
   2.6.9

Applications without a BUNDLED WITH value will receive a default bundler version .