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Code RoomNetcode desync risk
HardPrep Room Coding #4026

Netcode desync risk

Vibe & agenticConcurrencySenior–Staff~18 min

An agent wrote the client-side prediction-and-reconciliation code for a multiplayer game in C#. It feels smooth in your single-machine playtest and the diff looks coherent, but you didn't write it and netcode bugs (desync, jitter, mispredicted rollback) only appear under real latency and packet loss. How do you verify this before it ships to players?

Implement
reconcile_positions(input_deltas: list[int], acked_sequence: int, server_position: int) → list[int]
Examples
in[[1,2,3,4],2,10]out[10,13,17]
in[[1,2,3,4],4,10]out[10]
in[[5,-2,7],0,100]out[100,105,103,110]
What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.

0:00 of about 18 min

Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.