4 rounds total, first was typical phone screening, the second was more in depth technical interview with head of department. Asked some basic questions about enterprise experience, projects completed, and some Data Structure 101 type questions to test competency. 3 and 4 were coding interviews. The first was a more a leetcode type problem with 2 software engineers. Although I struggled a bit they gave me a couple hints and eventually I solved the problem. Ask questions at the end. Was told that generally solving the problem is enough and there isn't much optimization that goes on as long as everything can be automated. Made it to 4th round after over a week of silence. Asked 2 more coding problems by the same 2 engineers and the head of department. Completed both and was asked to optimize both for efficiency. Both lasted 1 hour each. After 4 rounds and another week and a half of silence was told they went with another candidate.