multiplayer-sync
Multiplayer Synchronization in Decentraland
Decentraland scenes are inherently multiplayer. All players in the same scene share the same space. SDK7 uses CRDT-based synchronization.
Runtime constraint: Decentraland runs in a QuickJS sandbox. No Node.js APIs (
fs,http,path,process). Usefetch()andWebSocketfor network communication. See the scene-runtime skill for async patterns.
Sync Strategy Decision Tree
Choose the right networking approach based on what you need:
| Strategy | Use When | Persistence | Example |
|---|---|---|---|
syncEntity |
Shared state that all players see and that persists for new arrivals | Yes — state survives player join/leave | Doors, switches, scoreboards, elevators |
MessageBus |
Ephemeral events that only matter in the moment | No — late joiners miss past messages | Chat messages, sound effects, particle triggers |
fetch / REST API |
Reading or writing data to an external server | Server-dependent | Leaderboards, inventory, external game state |
signedFetch |
Authenticated requests that prove player identity | Server-dependent | Claiming rewards, submitting verified scores |
WebSocket |
Real-time bidirectional communication with a server | Connection-dependent | Live game servers, real-time chat, authoritative multiplayer |
Decision flow:
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