The shape of the system
A realtime game is not one server. It is a fleet of specialized services that each own a narrow job, glued together so players feel a single coherent world.
The hot path is the game server, a process that runs one match, holds the live world state in memory, and exchanges tiny packets with players many times per second over UDP.
The supporting cast
- A lobby and matchmaking service groups players into balanced matches.
- A session orchestrator spins up a dedicated game server process and hands players its address.
- Backend services store accounts, inventory, stats, and leaderboards in durable databases.
- A gateway authenticates players and routes them, keeping secrets off the game process.
Why split it this way
- The game server must stay stateless toward storage during a match so it can run fast in memory.
- Persistent data lives in slower, durable systems that tolerate restarts.
- Each tier scales on its own axis, matches by CPU, storage by data size.
Key idea
A multiplayer game splits into a fast in memory match process backed by durable services so realtime play and persistent data scale separately.