The Bundler 1.14 announcement includes context and a more detailed explanation of the changes in this version. This is a summary of the biggest changes. As always, a detailed list of every change is provided in the changelog.
The conservative flag allows `bundle update --conservative GEM` to update the version of GEM, but prevents Bundler from updating the versions of any of the gems that GEM depends on, similar to changing a gem's version number in the Gemfile and then running `bundle install`.
As part of the compact index format provided by RubyGems.org, Bundler now has access to checksums for every .gem file. Starting with version 1.14, Bundler actively validates those checksums against downloaded .gem files before installing them. Hooray! 🎉
The `force_ruby_platform` and `specific_platform` settings tell Bundler to always compile gems and to consider platforms during dependency resolution, respectively. These options can significantly improve things for users installing a single bundle on more than one platform.
If any gem conflicts with your Ruby or RubyGems version, the error message will now show both the conflicting dependencies and the chain of parent dependencies that led to the conflict.