Software Engineer jobs in Chicago, IL

Design a data structure that supports insert, delete and get-random in constant time. Walk me through it as you code.

What they are checking: Whether they can reason about data structure trade-offs and write correct code while explaining it.

Here is a function that is slower than it should be. How would you figure out why and make it faster?

What they are checking: Whether they can read unfamiliar code, measure before guessing and improve it.

In C++, what happens in memory when you push into a vector that is full?

What they are checking: Whether they understand what their code does underneath, which matters for low-latency systems.

How would you design a system that receives market data updates and keeps the best bid and offer for thousands of symbols?

What they are checking: Whether they can describe a design at a high level and down to step-by-step detail.

Tell me about a project you built in your spare time. What was the hardest part?

What they are checking: Whether they truly love coding and tinkering, which the posting puts first.

Tell me about a time you found a bug that was really hard to track down.

What they are checking: Whether they have a methodical approach to debugging under uncertainty.

Write a function to merge k sorted streams and explain its time complexity.

What they are checking: Whether they know core algorithms like heaps and can analyze performance correctly.

A trading system you own crashes during market hours. What do you do first?

What they are checking: Whether they think about stopping harm quickly before finding the root cause.