Delta Updates Over Full Payloads
Sending only what changed shrinks bandwidth, accelerates perceived speed, and preserves battery life. Pins receive precise mutations: a quantity decrement, a price adjustment, a sold-out transition, or a currency display tweak. Client reducers apply diffs predictably, with defensive checks in case of out-of-order messages. On suspicion of drift, clients request a targeted resync that respects filters, keeping the map consistent without brute-force reloads or disorienting redraws.