Requestly is a lightweight proxy available as a browser extension & desktop app to intercept & modify network requests. Using Requestly you can Modify Headers, Redirect Url, Mock API response, Delay/Throttle requests, etc. Developers can collaborate by sharing rules with each other. Modify Headers - Add, Delete or Replace request & response headers. Can be used to test X-Frame-Options, Content-Security-Policy, Add authorization headers, debug CORS etc Redirect URL- Redirect requests matching a URL pattern to different destination URL. Can be used to load unminified scripts, test different library versions, load local version of script in production env etc Insert Custom Scripts - Allows you to automate, scrape & change webpage's behaviour with little knowledge of JS & CSS. Use File Hosting service to upload long scripts and get a URL to be used in your websites or Requestly rules Mock API Response - Return custom (mocked) response for your API requests. Can be used to test API changes, newer API version in your app