Demo case file · Technical
Mobile-first fintech
iOS Engineer
This is a demo case file: a realistic example written from commonly known interview formats, not a real candidate's interview experience.
Questions asked
- Implement a list that loads thumbnails from the network and scrolls smoothly with thousands of rows.
- How would you cache images in memory and on disk, and when would you evict them?
- The app is killed while a payment request is in flight. What should the user see when they reopen it?
What to expect
Swift in a shared Xcode session. They watched for main-thread work, cell reuse bugs (wrong image in a recycled cell) and cancelling downloads for rows that scroll away. The payment question was about idempotency and showing an honest "pending" state rather than guessing.
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