Practice System Design Until You're Ready
Practice 35+ real interview problems. Get specific feedback on what you missed. $19.99/month unlimited.
No credit card required
![prep[0] system design interview feedback interface showing detailed evaluation](/_next/image?url=%2Fscreenshots%2Fhero-screenshot.png&w=3840&q=75)
How It Works
Four simple steps to interview success
Pick a Problem
Choose from 35+ system design questions asked at Google, Meta, Amazon, and Netflix.
Complete Your Interview
Use chat, whiteboard, and voice to design your solution. Explain your decisions as you go.
Get Detailed Feedback
See exactly what you did well and what you missed. Specific, actionable feedback—not generic advice.
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
$25/month unlimited vs. $99+ per human mock interview. Available 24/7, no scheduling required.
Simple Pricing
Start free, upgrade when ready
Pro
Unlimited practice
$19.99/month
- ✓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
Ready to Start Practicing?
Try 2 free interviews. No credit card required. Takes 2 minutes.