Flutter + PowerSync + Supabase

A starter project to help you quickly set up and run a local environment with Flutter, PowerSync, and Supabase.

Prerequisites

You will need the following tools installed on your local machine:

• Docker
• Supabase CLI
• Flutter

Configuration

The ./supabase/config.toml file defines the configuration for your local Supabase instance.

The following settings have already been added and are required for this project:

• enable_anonymous_sign_ins = true - Allows clients to generate JWT tokens without signing in using an email/password or OAuth provider. The ./flutter_counter project is configured to sign users in anonymously.
• signing_keys_path = "./signing_keys.json" - Enables asymmetric JWTs for your local Supabase instance.

Getting Started

Copy the environment template file:

cp .env.local.template .env.local

1. Install the Supabase CLI (See the documentation for more installation options)

macOS

brew install supabase/tap/supabase

Windows

scoop bucket add supabase https://github.com/supabase/scoop-bucket.git
scoop install supabase

2. Generate Supabase Signing Keys

Run the following command to generate the ./supabase/signing_keys.json file.

supabase gen signing-key

3. Start Supabase locally

There is already a migration in supabase/migrations/20250819090132_counters.sql that creates the counters table, creates the powersync publication and seeds one counter record

supabase start

4. Start the PowerSync service

The sync rules are already configured in docker/powersync.yaml to sync all data from counters to all clients.

docker compose --file ./docker/compose.yaml --env-file .env.local up -d

5. Run the Flutter Counter Demo

cd flutter_counter

cp lib/app_config_template.dart lib/app_config.dart

flutter run