Day 6: what the chain actually does

Day 6. People keep asking what the chain actually does in a medical simulator, so here it is. Each patient is one account on Solana. It holds her state, who has her right now, and one hash: her last shift. That's it. Her chart isn't stored anywhere. When you open her, your browser pulls every shift ever anchored on her, replays the tapes through the same physics engine, and that's the chart. If our server lied, your replay wouldn't match. A shift is four small transactions. Commit (which case, without saying which). TakeShift (a ten-minute lease). You play in the browser, nothing on chain. AnchorShift, one leaf, and it becomes her new head. It carries the head you think you're extending. If someone anchored before you, the program says StaleHead and writes nothing. That rule caught our own demo driver before it caught anyone else. Costs: 10,000 lamports a shift, two signatures. Our relay pays. Nobody makes a wallet. What the chain doesn't do: judge the medicine. That's the rubric, replayable from the tape, shown separately. 32-second walkthrough attached. https://world.vitals.academy/?src=colosseum