What is Interview Forge?

Interview Forge helps you practice mock interviews, follow study plans, track career goals, review learning analytics, and prepare across 36 pages.

System Design Interview Questions

Original, in-depth guides written by engineers. Each page includes the approach, complexity, follow-ups, and a link to practice with AI feedback.

Design a URL Shortener (like bit.ly)

Easy

A complete, top-notch walkthrough for designing a URL shortener: requirements, capacity estimation, base-62 vs hashing, caching, analytics, and the trade-offs that decide the architecture.

Read guide

Design Uber (Ride-Hailing)

Hard

A deep walkthrough of a ride-hailing system: real-time driver-rider matching, geospatial indexing, the dispatch state machine, surge pricing, and the consistency trade-offs that make Uber hard.

Read guide

Design Netflix (Video Streaming)

Hard

A top-notch walkthrough of a global video streaming platform: the content pipeline, CDN strategy (Open Connect), adaptive bitrate, and the read-heavy architecture that serves billions of hours.

Read guide

Design Instagram (Photo & Feed)

Medium

A thorough design of Instagram: photo storage, the news feed fan-out decision, ranking, and the read-heavy social architecture behind a billion-user feed.

Design WhatsApp (Chat Messaging)

Hard

A deep design of a chat system like WhatsApp: connection management, delivery guarantees, group chat fan-out, presence, and end-to-end encryption implications.

Design YouTube (Video Sharing)

Hard

A top-notch walkthrough of YouTube: the upload and transcoding pipeline, search and recommendations, and the CDN strategy for the world's largest video platform.

Design Twitter (Timeline & Feed)

Medium

A thorough design of Twitter: the tweet write path, timeline generation (fan-out vs pull), the celebrity problem, and Snowflake IDs for time-sortable tweets.

Design Google Drive (File Storage & Sync)

Medium

A thorough design of a file storage and sync service like Google Drive: chunked uploads, content-addressed dedup, sync, and conflict resolution.

Design a Distributed Rate Limiter

Medium

A top-notch walkthrough of a distributed rate limiter: token bucket vs sliding window, where to place it, and how to coordinate limits across nodes.

Unlock 10 more system design interview questions

Premium members get every DSA, system design, company and role interview guide — plus AI practice, mock interviews, and analytics.

Unlock with Premium