coding 1: validate sudoku and follow-up solve sudoku.
Coudn't solve follow-up in time. Made a small error that was causing stackoverflow realized after the interview.

coding2: A variation of https://leetcode.com/problems/find-nearest-point-that-has-the-same-x-or-y-coordinate/
Solved it quickly. Interviewer asked for more optmized solution I gave ideas but he had his own approach in mind which really wasn't optmized in the worst case.

System Design - honestly struggled with this round. It was to design a scheduler as a service. Maybe It was just me I couldn't come up with requirements as smoothly as I would expect. I guess I need more practice. I've not thought about a problem like this so it was hard for me to quickly think of solutions.
I'd like to get an idea on how to approach this system design problem.

Thoughts: I knew I would be rejected after the system design but I didn't expect they would cite something like code quality as a reason. Didn't make any sense. or maybe it did.

For future doordash candidates, I suggest you solve all the leetcode tagged problems, they don't ask anything different. They are machines literally and won't guide you much during the interview. Its like an OA but some one is looking. They don't want anything short of full solution with all test cases passed. System design depends on the team you are interviewing for i guess.