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PowerSync SDK on NuGet

This SDK is distributed via NuGet

Source Code

Refer to the powersync-dotnet repo on GitHub

API Reference

Full API reference for the SDK

Example Projects

Gallery of example projects/demo apps built with .NET PowerSync

Changelog

Changelog for the SDK
This SDK is currently in a beta release. It is production-ready for tested use cases. APIs are stable, and we communicate breaking changes clearly.

Supported Frameworks and Targets

The PowerSync .NET SDK supports:
  • .NET Versions: 6, 8, and 9
  • .NET Standard: 2.0 (for compatibility with older libraries and frameworks)
  • .NET Framework: Version 4.8, which requires additional configuration (see the package README)
  • MAUI: Cross-platform support for Android, iOS, Mac Catalyst, and Windows (targeting net8.0 and net9.0 mobile frameworks)
  • WPF: Windows desktop applications
  • Console/CLI: Windows (x64, ARM), macOS (x64, ARM), and Linux (x64, ARM)
Current limitations:
  • Blazor (web) platforms are not yet supported.
For more details, see the package README.

SDK Features

  • Real-time streaming of database changes: Changes made by one user are instantly streamed to all other users with access to that data. This keeps clients automatically in sync without manual polling or refresh logic.
  • Direct access to a local SQLite database: Data is stored locally, so apps can read and write instantly without network calls. This enables offline support and faster user interactions.
  • Asynchronous background execution: The SDK performs database operations in the background to avoid blocking the application’s main thread. This means that apps stay responsive, even during heavy data activity.
  • Query subscriptions for live updates: The SDK supports query subscriptions that automatically push real-time updates to client applications as data changes, keeping your UI reactive and up to date.
  • Automatic schema management: PowerSync syncs schemaless data and applies a client-defined schema using SQLite views. This architecture means that PowerSync SDKs handle schema changes without explicit migrations on the client side.

Quickstart

For desktop/server/binary use-cases and WPF, add the PowerSync.Common NuGet package to your project:
To install a specific version, use --version instead: dotnet add package PowerSync.Common --version <version>
Prerequisites: Before you start, connect your source database to the PowerSync Service and deploy Sync Streams. These are steps 1-4 in the Setup Guide.

1. Define the Client-Side Schema

The client-side schema defines the tables and columns of the SQLite database that the PowerSync client SDK manages and that your app reads from and writes to. It is usually derived from your backend database schema and your Sync Streams, and it can also include local-only tables. You apply the schema when you instantiate the database in the next step. Schema migrations are not required. The SDK syncs schemaless data and applies the schema to that data with SQLite views. The exception is raw tables, which you create and migrate yourself.
Generate schema automaticallyIn the PowerSync Dashboard, select your project and instance and click the Connect button in the top bar to generate the client-side schema in your preferred language. The schema is generated from your Sync Streams. The CLI offers the same function.The generated schema does not include an id column. The client SDK creates an id column of type text automatically, so you do not need to declare it. See Client ID for details.
You can use this example as a reference when defining your schema. The available column types are text, integer, and real. These should match the values produced by your Sync Streams. If a value does not match, it is cast automatically. For details on how source database types map to SQLite types, see Types.

Schema Definition Syntax

There are two supported syntaxes for defining the schema: Attribute-based (recommended): Annotate a C# class with [Table], [Column], and [Index] attributes. The same class can then be used directly as the result type in queries, so you define your data structure once:
Unlike the other syntaxes where PowerSync automatically creates an id column, the attribute-based syntax requires you to explicitly declare it. The SDK identifies the id property by looking for either a property named id, or any property with a [Column("id")] attribute (case-insensitive). Having none or more than one is an error.
If you prefer to keep your schema definition separate from your data classes, you can use the object initializer syntax instead:

2. Instantiate the PowerSync Database

Next, instantiate the PowerSync database. PowerSync streams changes from your backend source database into the client-side SQLite database, based on your Sync Streams. Your app reads from and writes to this local database whether the user is online or offline. Example: The initialization syntax differs slightly between the Common and MAUI SDKs:

3. Integrate with Your Backend

The backend connector connects the PowerSync client SDK to your application backend. The SDK uses it to:
  1. Get an auth token to connect to the PowerSync instance.
  2. Upload client-side writes to your backend API. The SDK places every write to the SQLite database in an upload queue and uploads the queue to your backend when the user is connected. Your backend then applies the changes to the source database.
The connector must implement two methods:
  1. IPowerSyncBackendConnector.FetchCredentials - The SDK calls this method to get authentication credentials. It caches the credentials and calls the method again only when needed, for example on the first connection or when the token is near expiry. See When fetchCredentials() is Called for details and Authentication Setup for how to generate credentials.
  2. IPowerSyncBackendConnector.UploadData - The SDK calls this method whenever it has client-side writes to upload to your backend API. Implement how those writes are processed and uploaded. See When uploadData() is Called for triggers, throttling, and retry behavior, and Writing Client Changes for the app backend implementation.
Example:
With your database instantiated and your connector ready, call Connect to start syncing data with your backend:
This section assumes that you use PowerSync to sync your backend source database with SQLite in your app. To manage a local SQLite database without sync, instantiate the PowerSync database without calling connect() and see the Local-Only guide.

4. Subscribe to Sync Streams

Streams defined with auto_subscribe: true start syncing as soon as the client connects. For all other streams, your app must subscribe before their data downloads. The basic pattern is: subscribe to a stream, wait for its data to sync, then unsubscribe when the data is no longer needed.
After you unsubscribe, the synced data stays in the local database for the stream’s time-to-live (TTL), which is 24 hours by default. If the app subscribes again within that time, the data is already available. See Client-Side Usage for framework hooks, per-subscription sync status, custom TTLs, priority overrides, and connection parameters.

Using PowerSync: CRUD Functions

Once the PowerSync database is connected and your streams have synced, the data is in the local SQLite database. The most commonly used CRUD functions to interact with your SQLite data are:

Fetching a Single Item

The Get method executes a read-only (SELECT) query and returns a single result. It throws an exception if no result is found. Use GetOptional to return a single optional result (returns null if no result is found).

Querying Items (PowerSync.GetAll)

The GetAll method returns a set of rows from a table.

Watching Queries (PowerSync.Watch)

The Watch method executes a read query whenever a change to a dependent table is made. It returns an IAsyncEnumerable so you can use await foreach to consume results.

Mutations (PowerSync.Execute)

The Execute method can be used for executing single SQLite write statements.

Configure Logging

By default, the SDK uses a no-op logger that outputs nothing. To enable logging, configure a logger with .NET’s ILogger interface:

Additional Usage Examples

For more usage examples including accessing connection status, monitoring sync progress, and waiting for initial sync, see the Usage Examples page.

Troubleshooting

See Troubleshooting for pointers to debug common issues.

Supported Platforms

See Supported Platforms -> .NET SDK.

Upgrading the SDK

To upgrade the PowerSync package, run the following command in your project folder: