For the read path it hooks into Postgres logical replication or MongoDB change streams (and MySQL binlog soon). It supports partial syncing using declarative rules. For the write path, it allows writing to the local SQLite database and also places writes into an upload queue, and then uses a developer-defined function to upload writes to the backend API.
> Meanwhile for “local-only” it would be great to use sqlite in the browser + native file system API so that the db could be stored on the user’s file system and we wouldn’t have to worry about browser storage eviction. i think that could really open up a whole world of privacy preserving offline software delivered through the browser
Agreed. This is a limitation of IndexedDB and OPFS as persistent browser storage currently
For the read path it hooks into Postgres logical replication or MongoDB change streams (and MySQL binlog soon). It supports partial syncing using declarative rules. For the write path, it allows writing to the local SQLite database and also places writes into an upload queue, and then uses a developer-defined function to upload writes to the backend API.
We did a deep dive on current options for SQLite on the web, and are currently using an IndexedDB-based VFS, and looking to move to OPFS: https://www.powersync.com/blog/sqlite-persistence-on-the-web
We recently released an integration with TanStack Query to allow leveraging some of its features in conjunction with PowerSync: https://docs.powersync.com/client-sdk-references/js-web/java...
> Meanwhile for “local-only” it would be great to use sqlite in the browser + native file system API so that the db could be stored on the user’s file system and we wouldn’t have to worry about browser storage eviction. i think that could really open up a whole world of privacy preserving offline software delivered through the browser
Agreed. This is a limitation of IndexedDB and OPFS as persistent browser storage currently