What to work through
Work through a news feed as a spoken system design interview. Start by clarifying the scope, sketch a working design and explain the trade-offs behind your choices.
- Scroll a feed of posts from followed accounts, more loading as the reader goes
- Like a post and comment on it
- Write a post with text and photos
- Learn that new posts have arrived without a manual refresh
Constraints to discuss
- The first posts show within 2.5 seconds on a phone
- A tap answers within 200 milliseconds
- Scrolling stays at 60 frames a second with 100 or more posts loaded
- Usable with a keyboard and a screen reader
Need a starting point?
Watch for these common gaps as you prepare:
- Page numbers for a feed that new posts keep shifting
- Adding new posts to the top while the reader is scrolling
- Keeping every post ever loaded in the page
- Restoring the reading place by a pixel offset when post heights vary
- Leaving accessibility out: unlabelled buttons and no announcement of new posts
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.
- Meta: A senior candidate reports a product architecture round in December 2025: the frontend and the client-facing APIs of a news feed, with cursor pagination required.
- Meta: An L5 candidate reports "Design a News Feed system" as the design round after the coding screen, about May 2026; the track is not stated.
- Reddit: A frontend phone screen tip from October 2024: a feed, talked through rather than coded.
- Amazon: A frontend onsite design round tip from March 2025: a news website, with its data, its API and video.
- Rippling: Listed by PracHub in July 2026 as a frontend engineer question, with no candidate narrative.