Show HN: Mocktail – Free, open-source mock API server with a built-in dashboard

Mocktail v4, a free, open-source mock API server with a built-in dashboard and database, is now available as a single ~25 MB binary. The rebuild adds MCP support for coding agents and an optional built-in AI assistant using the user's own API key. The project is self-hosted and requires no account or hosted service.

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. Comments URL: https://news.ycombinator.com/item?id=49304062 https://news.ycombinator.com/item?id=49304062 Points: 1 Comments: 0