bundle package

Locks and then caches all of the gems into vendor/cache
$ bundle package [--no-prune]

Options:

--no-prune: Don't remove stale gems from the cache.

The package command will copy the .gem files for every gem in the bundle into the directory ./vendor/cache. If you then check that directory into your source control repository, others who check out your source will be able to install the bundle without having to download any additional gems.
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