Live data and payments case studies
These cases are about data that changes while the user watches, and about actions that must happen only once. You design streams of updates, holds that end on server time, and payments that are safe to retry. The hard parts are order, gaps, time and money. The stock ticker shows an app that is always online. The booking app shows how to stay safe when the result of a payment is not clear.
Main case studies in this topic
- Design a hotel or ride booking appHolds, server time, payments, and search.
- Topic
- Live data and payments Also: Offline and sync
- Starts at
- Mid-level (also in the staff track)
- Reading time
- 15 min read
Build guide: 18 min - Builds on
- Design a chat app
- Status
- Free
- Design a stock ticker appStreaming updates, limiting how often the screen changes, and an always-online app.
- Starts at
- Senior (also in the staff track)
- Reading time
- 14 min read
Build guide: 16 min - Builds on
- Design a chat app
- Status
- Free
This topic also appears in
The main topic of these case studies is a different one. Each one still teaches part of this topic.
- Design a chat appOutbox, safe retries (idempotent sends), and sync with WebSocket and push.
- Topic
- Offline and sync Also: Live data and payments
- Starts at
- Mid-level (also in the staff track)
- Reading time
- 15 min read
Build guide: 14 min - Builds on
- The five-step method
- Status
- Free
- Design a video streaming appLoading ahead (prefetch), adaptive bitrate, and playback state.
- Topic
- Feeds and media Also: Live data and payments
- Starts at
- Senior (also in the staff track)
- Reading time
- 15 min read
Build guide: 21 min - Builds on
- Design an image loading library
- Status
- Free
- Design a public transport appA timetable that works offline, live delays on top, and careful use of location and battery.
- Topic
- Offline and sync Also: Live data and payments
- Starts at
- Senior
- Reading time
- 6 min read
- Builds on
- Design a stock ticker app
- Status
- Free teaser
- Design a push notification SDKHow push tokens change over time, delivery, and deep links.
- Topic
- SDKs and libraries Also: Live data and payments
- Starts at
- Senior (also in the staff track)
- Reading time
- 15 min read
Build guide: 20 min - Builds on
- Design a chat app
- Status
- Free
Where these cases sit on the learning map
The blue boxes are in this topic. The boxes above them are the pages to read first. See the whole map.
- Case study
- Free teaser
- Guide
- In this topic
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