powersync 1.9.1

PowerSync Flutter SDK - sync engine for building local-first apps.

PowerSync SDK for Dart/Flutter

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.

This package (powersync) is the PowerSync client SDK for Dart/Flutter.

See a summary of features here.

Installation

flutter pub add powersync

Getting Started

Our full SDK reference contains everything you need to know to get started implementing PowerSync in your project.

Web support - Beta

Web support in version 1.9.0 is currently in a beta release. This means it is safe to use in production, provided that you've tested your use cases.

Demo app

The easiest way to test Flutter Web support is to run the Supabase Todo-List demo app:

1. Checkout this repo's main branch.

• Note: If you are an existing user updating to the latest code after a git pull, run melos exec 'flutter pub upgrade' in the repo's root directory and make sure it succeeds.

2. Run melos prepare in the repo's root
3. cd into the demos/supabase-todolist folder
4. If you haven’t yet: cp lib/app_config_template.dart lib/app_config.dart (optionally update this config with your own Supabase and PowerSync project details).
5. Run flutter run -d chrome

Installing PowerSync in your own project

Install the latest version of the package, for example:

flutter pub add powersync:'^1.9.0'

The latest version can be found here.

Additional config

Web support requires sqlite3.wasm and worker (powersync_db.worker.js and powersync_sync.worker.js) assets to be served from the web application. They can be downloaded to the web directory by running the following command in your application's root folder.

dart run powersync:setup_web

The same code is used for initializing native and web PowerSyncDatabase clients.

Limitations

The API for Web is essentially the same as for native platforms, however, some features within PowerSyncDatabase clients are not available.

Imports

Flutter Web does not support importing directly from sqlite3.dart as it uses dart:ffi.

Change imports from

import 'package/powersync/sqlite3.dart`

to

import 'package/powersync/sqlite3_common.dart'

In code which needs to run on the Web platform. Isolated native specific code can still import from sqlite3.dart.

Database connections

Web DB connections do not support concurrency. A single DB connection is used. readLock and writeLock contexts do not implement checks for preventing writable queries in read connections and vice-versa.

Direct access to the synchronous CommonDatabase (sqlite.Database equivalent for web) connection is not available. computeWithDatabase is not available on web.

Changelog

A changelog for this SDK is available here.

API Reference

The full API reference for this SDK can be found here.

Examples

For example projects built with PowerSync and Flutter, see our Demo Apps / Example Projects gallery. Most of these projects can also be found in the demos/ directory.

Found a bug or need help?

• Join our Discord server where you can browse topics from our community, ask questions, share feedback, or just say hello :)
• Please open a GitHub issue when you come across a bug.
• Have feedback or an idea? Submit an idea via our public roadmap or schedule a chat with someone from our product team.