Mockttp HTTP Mocking Server

Mockttp is a versatile JavaScript library for intercepting, transforming, and testing HTTP requests and responses. It serves as a powerful tool for integration testing by allowing developers to stub server responses, verify real HTTP requests, and even act as a transparent proxy for complex network debugging. Unlike in-process stubbing solutions, Mockttp operates at the network level, ensuring accurate testing of how entire stacks handle real-world HTTP traffic. The current stable version is v4.3.1, with major versions typically released on an annual cadence, focusing on modern Node.js environments and developer experience. Key differentiators include its ability to run tests uniformly in both Node.js and browser environments, support for transparent proxying and HTTPS interception (with built-in CA certificate generation), strong TypeScript typing, and features for safe, parallel test execution with enhanced debuggability.