PowerSync is a sync engine for building local-first apps with instantly-responsive UI/UX and simplified state transfer. Syncs between SQLite on the client-side and Postgres, MongoDB or MySQL on the server-side.

PowerSync Service

powersync-service is the monorepo for the core PowerSync Service.

The service can be started using the public Docker image. See the image notes

Monorepo Structure:

Packages

• packages/service-core

  • Core logic for the PowerSync backend server

• packages/jpgwire

  • Customized version of pgwire (used with Postgres)

• packages/jsonbig

  • Custom JSON and BigInt parser

• packages/rsocket-router

  • Router for reactive streams using RSocket

• packages/sync-rules

  • Library containing logic for PowerSync sync rules

• packages/types

  • Type definitions for the PowerSync Service

Libraries

• libs/lib-services

  • A light-weight set of definitions and utilities for micro services

• libs/lib-mongodb

  • A light-weight set of common logic and types for the MongoDB replication and storage modules.

Modules

• modules/module-mongodb

  • MongoDB replication module.

• modules/module-mongodb-storage

  • MongoDB bucket storage module.

• modules/module-mysql

  • MySQL replication module.

• modules/module-postgres

  • Postgres replication module.

Service

• service

Contains the PowerSync Service code. This project is used to build the journeyapps/powersync-service Docker image.

Docs

• docs

Technical documentation regarding the implementation of PowerSync.

Test Client

• test-client

Contains a minimal client demonstrating direct usage of the HTTP stream sync API. This can be used to test sync rules in contexts such as automated testing.

Developing

See the notes for local development instructions.