Rack middleware for blocking & throttling
Debugging toolbar for Rack applications implemented as middleware
Real HTTP Caching for Ruby Web Apps
Rack Middleware for handling Cross-Origin Resource Sharing (CORS), which makes cross-origin AJAX possible.
OAuth 2.0 Server & Client Library. Both Bearer and MAC token type are supported.
A Rack and Rails plugin for building offline web applications
A web server agnostic rack middleware for defining and applying rewrite rules. In many cases you can get away with Rack::Rewrite instead of writing Apache mod_rewrite rules.
Rack middleware for rate-limiting incoming HTTP requests.
Abort requests that are taking too long
Per-request global storage for Rack.