Multiplayer apps

Prompts for real-time multiplayer — lobbies, state sync, leaderboards.

Multiplayer apps push Convex’s real-time sync hardest. Foundation prompt:

**Goal**: A real-time multiplayer {game/tool} where players join a session and see each other's actions live.

**User**: Authenticated players. Each player joins a session via short code.

**Data**:
- `sessions`: { code, hostId, maxPlayers, status: 'waiting' | 'playing' | 'ended' }
- `sessionPlayers`: { sessionId, userId, joinedAt, score, state: any }
- `actions`: { sessionId, userId, type, payload, timestamp }

**Behavior**:
- Lobby: enter session code or create new; see who's joined
- Game: real-time state visible to all players; actions submit instantly
- Leaderboard: ranked by score in real-time
- End: results screen, "Play again" returns to lobby

**Constraints**:
- Sub-100ms perceived latency (use Convex reactive queries; optimistic local updates)
- Idle players auto-removed after 5 min
- Cleanup ended sessions older than 24h via scheduled function

Variations

Turn-based

Add: a currentTurn field; UI disables input when it’s not your turn.

Spectators

Add: read-only viewers who don’t take actions but see state.

Matchmaking

Add: skill-based matching (queue players by ELO, pair when ready).

Related

Multiplayer recipe

Full build walkthrough.

Real-time sync patterns

Architectural patterns.

Optimistic updates

Sub-100ms feel.