til/ruby/update-the-gemfile-bundled-with-version.md

Update The Gemfile Bundled With Version

When you run bundle install, whatever is the latest version of bundler installed locally will be used. Your Gemfile dependencies will be installed and the Gemfile.lock will be marked at the bottom with a signature for the version of bundler that was used.

# Gemfile.lock
...

BUNDLED WITH
   1.1.17

On future bundle install calls, a matching major version of Bundler will be used. If you'd like to migrate from 1.x.x to 2.x.x or vice versa, or even if you want to explicitly change minor versions, you can run:

$ bundle update --bundler=2.2.4

This will bundle your project with 2.2.4 and update the BUNDLED WITH section to reflect that.

Use the version that makes sense for you with the --bundler flag.

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