A backend is needed once data must be trusted, shared across devices, or synced between players in real time: authoritative leaderboards, cross-device saves, in-game purchases, or multiplayer. A purely local single-player game with client-side scores can run with no server at all.
At a glance
| Fact | Value | Source |
|---|---|---|
| Client-only leaderboard scores can be manipulated | no trusted server | docs.crazygames.com |
| Server authority prevents cheating and data tampering | logic runs server-side | docs.unity.com |
| Some platforms give cloud saves and leaderboards without your own server | SDK-managed backend | docs.gamepush.com |
You need a backend the moment some piece of game data has to be trusted, shared, or kept in sync outside the player’s own browser. A local puzzle game that only saves to localStorage or IndexedDB and never compares scores between players can ship with no server at all. The line gets crossed by: real-money or virtual-currency purchases, leaderboards where you need scores that can’t be edited by the player, cloud saves that follow the player across devices, and any multiplayer where two clients must agree on the same game state.
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How to decide, in order
- Local-only, single player: no backend. Save progress client-side with the Web Storage API or IndexedDB.
- Leaderboards on a portal: some portals accept scores directly from the client via their SDK – CrazyGames documents this as client-only submission, though scores “can be manipulated since the client is not a trusted environment.” If you need scores submitted from your own backend instead, that’s the server-side path the same docs describe.
- Purchases or anti-cheat-sensitive scoring: you need server authority – logic enforced on a server you control, as Unity’s Cloud Code docs describe, so a client can’t fake progress or currency.
- Real-time multiplayer: you need a game server plus a backend coordination layer; see how Amazon GameLift Servers or Nakama structure this.
Pitfall: don’t build your own backend before checking whether the portal or platform you’re publishing to already offers cloud saves and leaderboards without running a server – some game services bundle this in.
Sources
- Server authority – Unity Docs
- Leaderboards – CrazyGames Documentation
- heroiclabs/nakama
- How hosting with Amazon GameLift Servers works
- Getting Started – GamePush
- MDN: Web Storage API
Related questions
Can I add a leaderboard without running my own server?
Yes, if the platform’s SDK submits scores client-side, as CrazyGames documents; the trade-off is that client-submitted scores can be manipulated since the client isn’t a trusted environment.
Do I need a server just for cloud saves?
Not necessarily. Some platforms and services sync local progress across devices for you; check whether your publishing platform already offers this before building your own.
Last updated: 30 September 2026