We have been building SyncLite, an open-source platform to simplify offline-first application development.

If your application uses SQLite or DuckDB, SyncLite lets it continue using the local database as usual while synchronization happens in the background.

For SQL-based applications, SyncLite records transactions into transactionally consistent .sqlog files using SQLite as an open replication format. A background consolidator replays those transactions, derives row-level CDC and schema changes, and applies them transactionally to destination databases like PostgreSQL.

The same architecture supports both database replication and many-to-one data consolidation. For applications that don't work directly with SQL, SyncLite also provides Store Devices (CRUD APIs) and Streaming Devices.

SyncLite is open source and available for Java, Python, Rust, and native C/C++ ( nodejs, .NET, go in roadmap).

GitHub: https://github.com/syncliteio/SyncLite

We wouldd love your feedback on the architecture, developer experience, and whether this is something you would find useful for building offline-first applications.