Karate is the only open-source tool to combine API test-automation, mocks and performance-testing into a single, unified framework. The BDD syntax popularized by Cucumber is language-neutral, and easy for even non-programmers. Besides powerful JSON & XML assertions, you can run tests in parallel - which is critical for HTTP API testing.
Max Inspect is a Mac app for inspecting Mac apps. It shows you entitlements, code signing, dyld info and more.
AccessLint brings automated web accessibility testing into your development workflow. When a pull request is opened, AccessLint reviews the changes and comments with any new accessibility issues, giving you quick, timely, and targeted feedback, before code goes live.