Jane Street prep

Jane Street Senior (5–8 years) System design

#01

Design a real-time chat application like Slack or WhatsApp — Jane Street interview

Reported in Jane Street USA engineering loops. Mid-to-senior design spanning WebSockets, message storage, and presence.

Hard Read answer →

Jane Street Senior (5–8 years) System design

#02

Compare cache-aside, read-through, write-through, and write-back — Jane Street interview

Reported in Jane Street USA engineering loops. Caching patterns for system design and backend performance tuning.

Medium Read answer →

Jane Street Senior (5–8 years) System design

#03

How does a load balancer work and which algorithms would you choose? — Jane Street interview

Reported in Jane Street USA engineering loops. Infrastructure design question covering L4/L7 balancers and health checks.

Medium Read answer →

Jane Street Senior (5–8 years) System design

#04

Design a distributed caching layer for a high-traffic read-heavy application — Jane Street interview

Reported in Jane Street USA engineering loops. Senior system design combining sharding, eviction, consistency, and observability.

Hard Read answer →

Jane Street Senior (5–8 years) System design

#05

How does consistent hashing work and why is it used in distributed caches? — Jane Street interview

Reported in Jane Street USA engineering loops. Frequently asked in US system design rounds for CDN, cache, and sharding topics.

Hard Read answer →

Jane Street Senior (5–8 years) System design

#06

Design a news feed / home timeline for a social app — Jane Street interview

Reported in Jane Street USA engineering loops. Product + system design hybrid common at Meta, Twitter/X, LinkedIn, and Reddit US offices.

Hard Read answer →