Fig. 00 — system design practice
System design, drilled.
Short sessions on the tradeoffs that actually come up. Answer, get it wrong, find out why.
Fig. 01 — try one
Your API keeps each user's session in its own process memory. You add a second instance behind a round-robin load balancer. What breaks first?
How it works
- 01
Drill
Real scenarios with numbers attached, about a minute each.
- 02
Get it wrong
Every drill explains the reasoning, not just the answer.
- 03
Come back
The engine tracks what you miss and brings it back.
Free to drill.
Pro grades your written answers: €19/month or €159/year, with a 7-day free trial.
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