Puppeteer is a Node.js library which provides a high-level API to control Chrome/Chromium over the DevTools Protocol.

REST API client library for .NET

Comprehensive and user-friendly cloud platform for Load Testing, Speed Testing and Website & API Optimization and Monitoring

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.

Code, test, and deploy synthetic monitoring at scale.

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.