Design video platform and catalog system
Company: Apple
Role: Software Engineer
Category: System Design
Difficulty: hard
Interview Round: Onsite
Design two systems. For each, define scope, APIs, storage choices, scalability strategy, consistency model, and reliability/observability plans:
1) Video sharing platform: A YouTube-like service supporting video upload, transcoding to multiple bitrates, storage tiering, CDN delivery, metadata and search, user actions (watch, like/comment), and a recommendations interface. Estimate traffic/storage, design the ingestion pipeline, thumbnail generation, indexing, caching, and rate limiting; discuss multi-region availability, encryption/DRM, and cost trade-offs.
2) Catalog system: A large marketplace catalog modeling categories, attributes, and product variants; support item ingestion, versioning, deduplication, and moderation; design services for search/browse indexing, localization, and incremental updates; outline read/write APIs, caching, and consistency between source of truth (SQL/NoSQL) and the search index; address schema evolution, multi-tenant isolation, and backfill/reprocessing strategies.
Quick Answer: This System Design question evaluates proficiency in large-scale architecture, API and storage design, data modeling, scalability and consistency trade-offs, ingestion and indexing pipelines, CDN and caching strategies, and operational concerns such as reliability, observability, security, and multi-region deployments across video-sharing and marketplace catalog domains. It is commonly asked in technical interviews to test architectural judgment and trade-off reasoning, emphasizing high-level practical application and operational planning rather than low-level implementation details.