What kind of things should go into a Ruby gem as opposed to a Rails plugin?

I have a 开发者_C百科set of functionality that I am considering packaging so as to use them in multiple projects, but I can't decide whether to choose a gem or a plugin. What is the difference? Which one should I choose?

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Gem is currently acknowledged as the 'best practice' for Rails. (You can also package as a gem and include an install.rb so that your project can be optionally be installed as a plugin - see this Rails dispatch article).

Basically the only reason to go with a plugin is if your users will want to be able to modify the code more often than not, as it stores a copy in vendor/plugins. However, with the advent of bundler it's pretty simple to store your gems per repository as well and modify them.

If you go with gems, you get the advantages of dependencies, versions, and the functionality that rubygems.org offers for searching, alerts and so on.

Definitely make it a gem!