The twilio-ruby gem provides a simple way to secure webhooks in Ruby applications using Rack middleware. The middleware validates incoming requests from Twilio by checking the X-Twilio-Signature header, which is signed with the account's auth token. To use this middleware, you need to add it to your application's configuration and pass your auth token as an argument. This ensures that only requests from Twilio are processed, preventing sensitive data from being exposed. The middleware can be easily integrated into Rack-based applications, including Sinatra and Rails, with a single line of config in the production environment. By using this middleware, developers can secure their webhooks and protect against potential security threats.