CollabGrid streams only the widgets inside your viewport, holds each one with an atomic lock the instant it's clicked, and runs every checkout through a queue that physically can't double-spend.
The default state. The tenant positions the widget on the board and any shopper inside the viewport can claim it. Editable, streamable, and the only state a buyer can act on first.
The backend tracks each client's bounding box and pushes updates only for widgets you can actually see. Pan away and the stream follows you, not the whole board.
The moment a widget is clicked, an atomic Redis lock claims it. No two shoppers ever hold the same item — the race condition simply can't form.
Checkout decouples into a message queue that commits a single order per reservation. Flash-sale bursts drain through the queue instead of fighting over row locks.
Background a tab and its socket drops to a heartbeat-only state to free up resources. Refocus and CollabGrid fast-syncs the exact delta you missed — no full reload.
Movements faster than humanly possible across the grid coordinate system get flagged and throttled, so scripted buyers can't sweep limited drops.
For your first drop and a small crew.
For tenants running live, high-volume drops.