Built for developers and testers alike, SoapUI is the only open source tool that covers the entire testing spectrum (functional, security, load, mocking).

Integrate systems. Automate work. Accelerate your digital transformation with a single platform for integration and business process automation.

Robot Framework is a generic open source automation framework. It can be used for test automation and robotic process automation (RPA).

REST API client library for .NET

Design, debug, and test APIs locally or in the cloud

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