YOUR BRIEF
What to work through
Work through twitch as a spoken system design interview. Start by clarifying the scope, sketch a working design and explain the trade-offs behind your choices.
- A streamer broadcasts live audio or video
- Viewers watch the stream on any device and network
- Viewers post chat messages and see others’ in near real time
- Viewers find live streams to watch
BEFORE YOU START
Constraints to discuss
- Viewers see the stream a few seconds behind the streamer
- Chat messages reach viewers in under 200 ms (Hello Interview, for live comments)
- Millions of live streams at once, some with huge audiences
- Availability over consistency for chat
Need a starting point?
Watch for these common gaps as you prepare:
- Polling for new chat messages
- Treating live video like uploaded video and waiting for the full file
- Broadcasting every chat message to every server
- No plan for reconnects, so viewers miss or repeat messages
Why this question is in the collection
These sources connect the problem to company interview reports or preparation guides. They do not guarantee what a company will ask you.