Release Train & Code Freeze Boarding Simulator

Large mobile apps don't ship the instant a feature is ready — they ship on a fixed cadence, boarding features onto discrete "release trains" the way a rail platform boards passengers onto scheduled departures. This simulator models that queue explicitly: features become ready at random times, a code-freeze window before each train's departure decides whether a just-finished feature still makes the cut, and a probabilistic quality gate can bump even an on-time feature to the next train. The 3D view renders upcoming trains as a row of gates; each feature travels toward the gate it is mathematically assigned to and either boards on schedule or is visibly diverted, while live metrics track average time-to-ship, per-train utilization, and how much of the delay comes from the freeze cutoff versus quality-gate failures — the two levers real release managers tune against each other.