The interview included a fundamentals discussion covering topics like: - Explain common data structures and when you would choose arrays, linked lists, hash tables, heaps, and trees. - Compare the time and space complexity of merge sort, quicksort, and binary search. - What is multithreading, and what problems can happen when threads share state? - What is a deadlock, what conditions cause it, and how can it be prevented? - What does "big data" mean in practice? - What are primary keys and foreign keys in a relational database?