Burp or Burp Suite is a set of tools used for penetration testing of web applications. It is developed by a company named Portswigger who make freely available a Web Security Academy which has a range of lessons on penetration testing.

Playwright enables reliable end-to-end testing for modern web apps.

Unifying API testing, API Performance testing, API Mocks and UI testing.

Test, scrape, generate, and automate without the pain and expense of hosting your own headless browsers.

Bruno is a Fast and Git-Friendly Opensource API client, aimed at revolutionizing the status quo represented by Postman, Insomnia and similar tools out there.

Requestly is an open-source tool that simplifies API development, testing, mocking, and integration for developers and QAs.