Quick answer: Store every input with a sequence number, snap to the last acknowledged server state, then re-simulate all inputs the server has not yet processed.
Client-side prediction only feels smooth if reconciliation replays pending inputs. Snapping to the server position without re-applying in-flight inputs rubber-bands the player back in time every correction.
How to fix it
1. Number and retain inputs
Tag each input command with an incrementing sequence id and keep it in a ring buffer until the server acknowledges that sequence in its state update.
2. Reconcile then replay
When a server state arrives, set the player to that state, discard inputs at or below the acknowledged sequence, then re-run the remaining buffered inputs through the same movement code to reach the present.
3. Use one deterministic move function
Run the exact same movement and collision code on client and server for the replay. Any divergence between the two implementations turns reconciliation into constant correction.
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 errors you never hear about are the ones quietly costing you players. Visibility turns them into a worklist.