Instacart Software Engineer Interview Experience — VO Split Into VO1/VO2, Karat AI-Coding Round

I got hit with Instacart's VO reform. The onsite is now split into two parts, VO1 and VO2 — if you fail VO1, there's no VO2, that's just it.

VO1 has three rounds:

First, the Karat round, which is AI coding. I hadn't used AI tools in a while so I wasn't used to it, and I only got through the fourth question before time ran out. The questions were:

Given a codebase on a bus route simulation:

1. How do you reduce the number of simulated people?
2. How does the bus pick up and drop off people — how do you decide who gets on, make sure you don't go over capacity, and track how many people are on the bus?
3. Look at the logs and find the bug (using AI makes this part go fast).
4. Support a priority pass.

The next two coding rounds were both well-known problems from the forum — password decoder and expression. I really want to flag this: don't just practice the hack2hire version of these two, that's only part one. The full versions have been posted on the forum separately.

I only found that out after my interview was already over 😭 I regret not searching more beforehand. Overall I didn't answer smoothly — I did get to working answers, but they weren't bug-free.

Good luck everyone. I've failed way too many interviews this year.

Update (2025-12-03): btw does anyone know how to deal with brain fog? The moment it gets to coding, my brain just locks up and goes blank. I've failed so many coding rounds because of it.