Mockr
A production mock API server in Go. Config-driven endpoints, hot reload, rate limiting, and a hardening pass so it can sit in a pipeline without becoming the weak link.
Frontend and integration work kept stalling on backends that were not ready, flaky, or too expensive to stand up for every branch. The usual mock tools were either toys or a second product to operate.
A single binary that reads a JSON config, serves the contract, and reloads when the file changes. Request validation, delays, status codes, health checks, and graceful shutdown are first-class. It runs with a read-only filesystem when you want it locked down.
Local and CI environments get a stable API surface without waiting on a real service. Teams can break the contract on purpose, then put it back, without standing up a stack.