Hi HN, I built the first version of Mocktail years ago. I recently came back to the project, and after a pretty substantial rebuild, v4 is now out.Mocktail is a free and open-source, self-hosted mock API server with a built-in dashboard and database, packaged as a single ~25 MB binary. You can run it locally or on your own infrastructure — no account or hosted service required.You can define endpoints and responses, generate realistic data per request, customize headers, status codes and latency, and inspect incoming requests in real time.With v4, I also added MCP support, so coding agents can create and manage mocks directly, along with an optional built-in AI assistant using your own API key. Both are completely optional.It’s been fun coming back to something I built years ago and bringing it up to date. I’d love to hear what you think, especially anything you’d change or add.