Practice System Design
Until You're Ready
35+ real interview problems. Specific feedback on what you missed. $19.99/month unlimited.
How It Works
Three simple steps to interview success
Pick a Problem
Choose from 35+ system design questions asked at Google, Meta, Amazon, and Netflix. From URL shorteners to distributed caches.
- Real questions from actual interviews
- Difficulty levels for all experience
Complete Your Interview
Use chat, whiteboard, and voice to design your solution. Explain your decisions as you go, just like a real interview.
- Interactive whiteboard for diagrams
- Voice input for natural conversation
Get Detailed Feedback
See exactly what you did well and what you missed. Specific, actionable feedback—not generic advice.
- Technical depth scoring
- Specific areas for improvement
Real Interview Questions
35+ problems from Google, Meta, Amazon, and Netflix. URL shorteners, Instagram feeds, distributed caches—the same questions asked in real interviews.
Detailed Feedback
Know exactly what you missed—cache invalidation, RTO/RPO quantification, capacity planning. Not generic "work on depth" advice.
Unlimited Practice
$19.99/month unlimited vs. $99+ per human mock interview. Available 24/7, no scheduling required.
Simple Pricing
Start free, upgrade when ready
Pro
Unlimited practice
- Unlimited interviews
- All 35+ problems
- Track progress over time
- Available 24/7
Compare: Human mock interviews $99-149 per session • Video courses $50-200 with no personalized feedback • prep[0] $19.99/month unlimited
Start Practicing Today
Try 2 free interviews. No credit card required. See exactly where you stand.