Design the "this month's spending and remaining limit" card in a credit card app. The screen has to open even on a flaky network, and the data has to feel fresh. Focus on what you cache and when you trust local data.
Read-only data is shown stale-while-revalidate, cached value first and refreshed in the background, but every amount is stored and displayed with its asOf time. Writes are either blocked offline or go through an outbox with an explicit "pending" state. On conflict the server always wins and the client reverts.
iOS system designShort answerAdvanced
Design an infinite-scroll feed screen like Twitter's from the iOS client's point of view…
#offline #cache
PersistenceShort answerExpert
You need to sync a notes app's local database with the server. Downloading everything…
#offline #conflict
iOS system designShort answerBasics
Design a simple notes app. Walk me through the architecture, how you store the data, and…
#conflict
iOS system designShort answerBasics
Design an app that shows the weather for the current location and favorite cities. Focus…
#cache