powersync-community/powersync-convex-todolist-demo

This repository is a demonstration app that shows how to build a to-do list that works offline and automatically syncs your data when you are back online. It solves the challenge of keeping a local copy of your data in sync with a cloud backend without requiring a separate server you have to build and manage yourself. The app uses PowerSync to handle the sync layer. When you add or complete a to-do item, that change is first written to a local SQLite database sitting right in your browser. PowerSync then queues those changes and uploads them to Convex, a backend-as-a-service that stores the data in the cloud. When any other client connects, PowerSync streams the latest changes back down, so every device sees the same state. Authentication is handled by Convex Auth using email and password sign-in, so there is no separate Node.js backend to write. The frontend is built with React and TypeScript, uses Vite as the development toolchain, and includes Material UI for the demo interface. For local development, the entire backend stack, meaning PowerSync Service, Convex, and MongoDB, runs inside Docker containers and is started with a single command. A demo mode is also included for environments like GitHub Pages where no backend is available. In that mode all writes stay local in the browser and no account is needed. A hosted live demo is linked in the README so you can try the app without installing anything.