Jest is a delightful JavaScript Testing Framework with a focus on simplicity.

Generate diagrams that visualize concepts, brainstorms, and web pages in seconds.

Swagger UI allows anyone — be it your development team or your end consumers — to visualize and interact with the API’s resources without having any of the implementation logic in place

The world’s first API testing platform that auto-generates unit test cases with dependency mocks from API calls. Using advanced AI, it simplifies test creation, debugging, and evolution, ensuring comprehensive coverage and boosting software quality.

AI agents that test your software on demand. Fracten tests your application 24/7, catches frontend bugs, and prevents software regressions

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.