Show HN: Chapplin – a type-safe, all-in-one framework for the ChatGPT Apps SDK

1 points by ssssota 3 hours ago

I built chapplin, a small framework for making ChatGPT Apps. The Apps SDK gives only low-level primitives, and building UI means bundling a single HTML file with all JS/CSS inside an MCP server. The build setup and type sharing became painful, so I made a tool that hides the build process and provides a type-safe setup end-to-end.