solsocket

Socket.io for Solana. Realtime multiplayer rooms — fully onchain, powered by MagicBlock Ephemeral Rollups.

npm install solsocket

import { SolSocket } from "solsocket";

const sock = SolSocket.connect({ wallet, cluster: "devnet", region: "eu" });
const room = await sock.joinOrCreate<State>("lobby"); // same name → same room

room.onPresence(({ player, data }) => drawCursor(player, data)); // ~50ms
await room.broadcast({ x: 0.4, y: 0.7 }); // zero-fee, no wallet popup

room.onMessage("chat", ({ player, data }) => bubble(player, data));
await room.emit("chat", { text: "gm" }); // event in tx logs — no state write

• One wallet signature creates a room, joins it, and delegates it to an ephemeral rollup — a single base-layer transaction.
• Zero-fee realtime writes signed by an auto-managed session key (localStorage), so there are no popups after join.
• ~50ms updates via processed-commitment websocket subscriptions straight from the ER — not 4–8s HTTP confirm polling.
• Real Solana state: rooms and presence are ordinary accounts; leave() and closeToBase() commit them back to the base layer.

API

| Call | What it does | |---|---| | SolSocket.connect({ wallet, cluster, region? }) | wallet = adapter or Keypair; cluster = "devnet", "local", or custom; region = "asia" \| "eu" \| "us" | | sock.joinOrCreate<T>("name", opts?) | named room — every client asking for "lobby" lands in the same room | | sock.createRoom<T>(opts?) | create + join + delegate in one tx → Room<T> | | sock.joinRoom<T>(address) | join an existing room (handles rejoin/lost session) | | sock.listRooms() | every room live on the ER with player counts, busiest first | | sock.peekState(address) | read any room's state without joining — leaderboards, lobby previews | | sock.spectate(address) | watch a room read-only: live subscriptions, zero transactions, wallet never needs funding | | room.broadcast(data) | write your presence slot (fire-and-forget) | | room.emit(name, data) | ephemeral event in tx logs — chat, hits, reactions; no state write | | room.setState(data) | write the shared room state | | room.onPresence(cb) / room.onStateChange(cb) / room.onMessage(name?, cb) | subscribe; returns unsubscribe fn | | room.getState() | read current shared state from the ER | | room.leave() | commit + undelegate your presence (session-signed) | | room.closeToBase() | creator: commit + undelegate the room |

Helpers: trackPresence(room, { onJoin, onUpdate, onLeave }) — roster with staleness sweeping (no ghost avatars) — and smoothPresence(room, render) — entity interpolation that renders 10Hz broadcasts as 60fps movement.

State, presence, and messages each take their own pluggable codec (Room<TState, TPresence, TMessage>): JSON by default, structCodec for compact binary structs (a full avatar in ~20 bytes), rawCodec for bytes.

The on-chain program (solsocket-engine) is deployed on devnet at CrLS1Ry58q59AgmqbNVrqbfs2bWGJtjk12PezXh4LeYh.

Full docs, Anchor program source, and a shared-cursor demo: github.com/Pratikkale26/solsocket

MIT © Pratik Kale