Canvas

Canvas is an embedded application database, similar to Firebase or Supabase, with full programmability & peer-to-peer instant sync.

It allows you to build multiplayer, real-time, and local-first applications, where each application is defined as an off-chain TypeScript smart contract.

Canvas applications are easy to configure and have several useful properties:

• Instant sync. No transaction fees or confirmation wait times. Any number of peers can concurrently execute new actions, without waiting for consensus.
• Real-time p2p. Peers connect and sync directly with each other over libp2p, and use GossipSub topics to broadcast actions.
• Eventually consistent. Actions can freely read and write to a relational database. Every peer's database state will deterministically converge regardless of the order in which the actions are received.
• Self-authenticating. Every action is signed by a session key authorized by a cryptographic identity, e.g. a Sign in with Ethereum address or did:plc identifier. The entire action log can be verified and replayed by anyone at any time; applications are trustless and portable.
• Cross-platform. Canvas apps run in the browser, server, or mobile devices. They persist data to IndexedDB in-browser, SQLite with on-disk storage, or Postgres with an in-memory Merkle index.

Canvas is designed to be maximally interoperable and data-agnostic. We expect to support a wide range of signed data formats, plus the ability to sync Canvas networks to blockchain data sources.

For more information, see the Canvas documentation.

Using Canvas

To install the latest published CLI:

npm install -g @canvas-js/cli

Commands

• canvas init <path>: Initialize a sample application
• canvas info <path>: Display application metadata
• canvas run <path>: Run an application
• canvas export <path>: Export the action log as JSON to stdout
• canvas import <path>: Import an action log from stdin

You can run each command with --help for more detailed documentation.

Contributing

Canvas is currently developed and maintained by a small team. For suggestions or contributions, we recommend first opening an issue or discussing with an existing contributor before opening a pull request.

For information about how to build this repo, see DEVELOPING.md.

License

MIT © Canvas Technologies, Inc.