Bundler version 2.5.23 is now available for Ruby apps
Change effective on 06 January 2025
The Ruby Buildpack installs a version of bundler based on the major and minor version listed in the Gemfile.lock under the BUNDLED WITH key:
BUNDLED WITH2.5.x will receive bundler2.5.23
It is strongly recommended that you have both a RUBY VERSION and BUNDLED WITH version listed in your Gemfile.lock. If you do not have those values, you can generate them and commit them to git:
$ bundle update --ruby
$ git add Gemfile.lock
$ git commit -m "Update Gemfile.lock"
Applications without these values specified in the Gemfile.lock may break unexpectedly when the defaults change.