Quick answer: Validate movement and action rates server-side against time, reject impossible speeds, and use server-authoritative timing rather than trusting the client.
Speed hacking is trusting client timing. Server-side validation fixes it. Here is how.
How to fix it
1. Validate rates server-side
Validate how far players move and how often they act against server time, rejecting anything faster than the rules allow. A speed hack produces movement and action rates the server can detect as impossible.
2. Use server-authoritative timing
Drive timing from the server, not the client's clock or frame rate, so a client running fast does not make the game run fast. Trusting client-reported time or movement is what lets speed hacks work.
3. Reject and correct impossible values
When a client reports impossible speed or timing, reject it and correct the player to the authoritative state. Combined with server-side rate validation, this neutralizes speed hacks rather than letting them affect the game.
Catching the ones you can't reproduce
The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.
Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.
This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.
The bug you can't reproduce isn't gone — it's just invisible until you capture it from the player's device.