WatermelonDB

What WatermelonDB is

WatermelonDB is a free, MIT-licensed reactive database framework for React and React Native applications. It is built for offline-first apps that synchronize local data with a remote database. Records load lazily, and queries run directly on SQLite on a separate native thread; the project describes its target scale as hundreds to tens of thousands of records. When records change, dependent UI components update automatically. WatermelonDB provides sync primitives and a built-in adapter for backend endpoints that follow its sync protocol, but developers must provide their own backend. The documented setup uses SQLite for React Native and Node.js, and LokiJS for web. Documentation also describes an optional RxJS API and a JavaScript API for other UI frameworks. React Native Windows support is experimental, requires JSI, and does not implement Turbo Sync. The sync documentation notes that a push can fail if a record changes remotely between pull and push, and pushed changes may be pulled again on a later sync. The project invites contributions and issue reports, and links to Stack Overflow for community help.