Voiden is a developer-first API client with local storage, Git-integrated, all based on markdown + offline support.

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

Fast, easy and reliable testing for anything that runs in a browser, Cypress is the new standard in front-end testing that every developer and QA engineer needs.

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

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

Free & OpenSource REST API Testing Tool for all levels in a Test Pyramid