Guides

How Rails extensions work, and how to choose, audit and upgrade the gems in your Gemfile.

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  From plugins to gems and engines: how Rails extensions evolved

  How Rails extensions moved from vendor/plugins to gems, Railties and engines between Rails 2 and Rails 4, and what that means when you read old tutorials or upgrade an old app.

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  How to evaluate a Rails gem before adding it to your Gemfile

  A practical checklist for judging a Ruby gem: maintenance signals, compatibility with Rails 7 and 8, dependencies, licence, and security advisories with bundler-audit.