Design a Video Call App – Frontend System Design

We’ll walk through the frontend system design for a browser-based video conferencing app like Zoom or Google Meet. Our goal is a meeting room that a user can join from a URL, preview camera and mic, then sit in a grid that grows from a 1:1 view into a tiled stage as people arrive. We’ll keep signaling, media, and REST on separate paths, and we’ll treat the tile grid as a subscription problem — not a “mount every remote video” problem. Put simply, the task is to design a video call app whose UI stays responsive as people join and leave.

Interviewers want to see that you know why mesh falls over, how an SFU plus simulcast keeps 25 cameras watchable, and how the UI stays up when ICE fails or a tab goes to the background. You’ll see estimates for one room, the component split, the join workflow, and the edge cases that separate a demo from a product.

Problem Statement

Build... premium content.