Klaviyo·Software Engineer·Onsite - System Design / Architecture
May 2026
Klaviyo SWE interview threw a pretty involved system design question at me, the kind where you realize halfway through that the edge cases are the whole point. One question, but it had enough moving parts to fill an entire session.
- Design and implement an in-memory banking system supporting scheduled transfers with expiry, account merges, and historical balance queries. Define the data structures, APIs, and algorithms you'd use, then write a working single-threaded implementation.
“This one wrecked me a little.”