temporal

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Temporal is a software company that provides an open-source durable execution platform for building reliable, scalable distributed applications and microservices. Its technology helps developers manage long-running workflows and orchestrate complex business processes with built-in fault tolerance and state management.

4 interview notes · updated Jul 2026

temporal·Software Engineer·Technical Phone Screen

May 2026

Temporal SWE interview threw a concurrency design problem at me that looked deceptively simple on the surface. The real meat was in the early-exit behavior and what you do with threads still running after you get your answer.

You have a slow API function that takes 1 to 10 seconds and returns a boolean. Given a list of indices, implement a function that runs the API calls in parallel and returns true as soon as any single call returns true, without waiting for the rest to finish.

“My first instinct was a thread pool with map() and I wrote that out, then they asked me to walk through what happens when the first True comes back.”

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temporal·Software Engineer·Onsite - System Design / Architecture

May 2026

System design round at Temporal for a software engineer role. The whole session was basically one big question about building a chat system, but it branched into a lot of sub-topics fast and I felt like I was constantly context-switching between transport layer stuff and distributed systems theory.

Design a 1-on-1 chat system end to end, covering client connectivity, message delivery, persistence, and read receipts.
Walk through your message pipeline using Kafka. What consumer latency do you expect, what delivery semantics do you use, and how do you partition by conversation?
How does Kafka differ from Redis as a backing store for a messaging system, and when would you choose one over the other?
How do you handle fan-out to a recipient who is online versus sending a push notification when they are offline?
How do you guarantee message ordering within a conversation?
How would you implement online and offline presence detection?

“This felt manageable at first but the scope kept expanding.”

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temporal·Software Engineer·Technical Phone Screen

Apr 2026

Temporal SWE interview with a log aggregation coding problem. Pretty focused on getting the implementation right under pressure, nothing wildly unexpected but the normalization detail was easy to fumble if you weren't paying attention.

Given a list of log entries where each entry has a timestamp, error code, link, and API name, produce an aggregated output grouped by unique (errorCode, API, normalized_link) tuples with occurrence counts. The normalization rule: replace every digit in the link with '#'.

“The normalization part is where I almost tripped up.”

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temporal·Software Engineer·Onsite - System Design / Architecture

Apr 2026

System design round at Temporal for a software engineer role. The whole interview was one big question about building a delayed event firing system at massive scale, and it went pretty deep pretty fast.

Design a system that schedules and fires a very large volume of events at specific future times, guaranteeing each event fires exactly once at its target time. Cover storage, dispatcher design, scaling, retry semantics, fault tolerance, clock skew, and how you'd push it to billions of events.

“This is the kind of question where you feel good for the first ten minutes and then realize you've barely scratched the surface.”

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