Show HN: FastApps – zero-boilerplate framework for building ChatGPT apps

fastapps.org

2 points by zachpark 16 hours ago

Building interactive widgets for ChatGPT turned out to be way more complex than I expected. Between the MCP protocol, widget registration, build setup, CSP policies, and resource serving — I kept writing the same boilerplate over and over just to get something basic working.

That’s why I built FastApps, an open-source framework that lets you build ChatGPT apps with only two files: a Python backend and a React frontend.

It removes all the glue code and focuses on developer experience:

- Auto-discovers and registers MCP widgets automatically

- Builds and bundles React UIs with zero config

- Manages CSP, metadata, and resource serving out of the box

- Type-safe data flow with Pydantic and React hooks

- Runs as an MCP server, fully compatible with ChatGPT and other MCP clients

If you’ve been experimenting with MCP or building ChatGPT tools, I’d love your feedback. It’s fully open source — and I’m looking for contributors who want to help shape this ecosystem together.

GitHub → https://github.com/DooiLabs/FastApps

Docs → https://www.fastapps.org/

donebydone 13 hours ago

Oh nice. I actually thought about building something similar. Did you benchmadk the one Vercel made for nextjs?

rosaaie 16 hours ago

looks promising. So is this basically just a codegen tool or scaffolding to save some boilerplate or is it an actual runtime framework that keeps running alongside the chatgpt?

  • zachpark 16 hours ago

    It’s an actual runtime, not just scaffolding. FastApps runs as an MCP server and it handles widget registration, protocol messages, static assets, and the data flow between backend and frontend.

    When you run fastapps create, you get a running service that ChatGPT talks to over MCP, not just a code template. You can extend or deploy it like any other web app.

    • freakynit 12 hours ago

      This is really well done.

      Any scope for backend-only part? Also, couldn't find examples for nodejs.. is it supported?

      Thanks..

    • rosaaie 16 hours ago

      Makes sense. How opinionated is it about the frontend? I saw React in the docs or can I use something else?

      • zachpark 16 hours ago

        Right now it's React-first because the Apps SDK UI layer is React-based. But the frontend is bundled automatically, so if OpenAI expands support for other frameworks later, swapping it out would be straightforward.