High-Level Design rounds at Walmart lean toward large consumer- and retail-scale systems — video streaming, e-commerce platforms, and dynamic pricing — rather than generic templates. Interviewers reward a structured approach: requirements first, then storage and data model, then delivery and scaling trade-offs.
Problem 1Design a Video-Streaming Platform
Design a video-streaming platform comparable to a major consumer streaming service (Netflix/Hotstar-style) for a large audience. You won't be handed explicit QPS or user-count numbers up front — you're expected to reason about and size the storage and delivery needs yourself.
Requirements to clarify first
- Is this on-demand only (a fixed catalog of movies and episodes) or does it also need live streaming, which changes the whole delivery path?
- What is the catalog size and audience we should size for — say 10,000 titles and 50 million monthly viewers with a few million concurrent at peak — and which regions must be served with low latency?
- Which parts must be strongly consistent (entitlements, payments, parental controls) and which can lag by seconds or minutes (view counts, recommendations, continue-watching position)?