Because you don't allow strangers into your app, and OAuth 2.0 is the new awesome.

Rack::URISanitizer is a Rack middleware which cleans up trailing % characters in request URI.

rack-oidc-api provides a JWT validation middleware which automatically discovers the settings supported by a given OIDC provider, and validates the token against the published keys.

Live broadcast on app showing fire and blood everywhere? Image hosting site flooded with pornography? Or some other urgent reason to take your app offline in a hurry? rack-killswitch to the rescue.

rack-auth-nginx_omniauth_adapter works with NginxOmniauthAdapter

rack-metrics is a performance monitoring tool.

RackTest driver for Capybara, with a Rack server started. So you can access the internal API of your application in your tests, with a script which live outside of Rails application, while keep the tests run as fast as lighting with the RackTest driver.

This gem is deprecated - see rack-tail

RackDispatch is a Ruby library that makes it simple to build elegant and powerful web applications with Rack. RackDispatch provides a base class for defining your application topology and handlers to perform common server- side tasks.

Rack-Rscript is a light-weight alternative to Sinatra-Rscript.

rack-relativize relativize path of html ( href, src attribute) and css ( url(..) ).

rack-session-stack

rack-smusher uses the smusher gem to compress your images dinamically

rack-weinre inserts a script tag that loads a weinre target js into html files.

Simple testing API built on Rack

Rack middleware for creating HTTP endpoints for files stored in MongoDB's GridFS

Rack middleware for Weixin apps: message validation/parser/generator

Tools for monitoring Rack apps in production.

Rack middleware and appilcation for serving dynamic pages in very simple way, without controllers or models, only views similar to ASP, JSP and PHP.

Rack middleware Captcha verification using Recaptcha API.