Siege : Siege is an http load testing and benchmarking utility. It was designed to let web developers measure their code under duress, to see how it will stan...
Browserling : Live interactive cross-browser testing
Mock Service Worker : Mock by intercepting requests on the network level. Seamlessly reuse the same mock definition for testing, development, and debugging.
Locust : A modern load testing framework
Define user behaviour with Python code, and swarm your system with millions of simultaneous users.