This extension is part of the Sinatra::Contrib project. Run gem install sinatra-contrib to have it available.


Sinatra::Extension is a mixin that provides some syntactic sugar for your extensions. It allows you to call directly inside your extension module almost any Sinatra::Base method. This means you can use get to define a route, before to define a before filter, set to define a setting, a so on.

Is important to be aware that this mixin remembers the methods calls you make, and then, when your extension is registered, replays them on the Sinatra application that has been extended. In order to do that, it defines a registered method, so, if your extension defines one too, remember to call super.


Just require the mixin and extend your extension with it:

require 'sinatra/extension'

module MyExtension
  extend Sinatra::Extension

  # set some settings for development
  configure :development do
    set :reload_stuff, true

  # define a route
  get '/' do
    'Hello World'

  # The rest of your extension code goes here...

You can also create an extension with the new method:

MyExtension = do
  # Your extension code goes here...

This is useful when you just want to pass a block to Sinatra::Base.register.

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