StubServern

StubServern is a software tool designed to create lightweight HTTP mock servers for software development and testing. It enables developers to simulate backend services, allowing client code to run against predictable responses without depending on real systems. The project emphasizes simplicity, fast startup, and predictable behavior in diverse environments.

Core capabilities include declarative mappings that define how the server should respond to specific requests. Mappings can match on HTTP method, URL path, headers, query parameters, or body content, and they map to configured responses such as fixed payloads, templated data, or dynamically generated content. Advanced options support latency simulation, failure injection, and multiple response criteria to cover edge cases. The tool typically reads mappings from a directory of configuration files and can serve multiple environments simultaneously.

StubServern architecture centers on a small, standalone server component that can run as an executable or be embedded as a library. It exposes a management interface to add, update, and inspect mappings, and often includes a command-line interface or REST API for automation. Some deployments offer an in-process mode for integration testing within a test suite.

Typical use cases include API development with incomplete backends, integration and end-to-end testing, and front-end development that requires stable, controllable responses. In continuous integration setups, stub servers provide deterministic behavior for tests that would otherwise depend on unstable services. The project is commonly compared with other API mocking tools and incentivizes quick iteration with hot-reload capabilities.