Object-Oriented Design Interview1

Interviews on Object-Oriented Design (OOD) are becoming increasingly popular in technical hiring. Large companies, such as Amazon, Bloomberg, and Uber, use them as a practical programming exercise to assess a candidate’s ability to build logical, maintainable systems and apply object-oriented design principles and patterns. Unlike algorithmic tasks, where a single optimal answer is important, OOD interviews leave room for creativity: the same task can be solved in different ways. Questions can pertain to real-world systems (for example, "Parking Lot" or "Vending Machine") or more abstract tasks ("File Search in Unix" or "Tic-Tac-Toe"). Companies use these interviews to find developers capable of writing clean, understandable, and scalable code quickly. Successfully passing an OOD interview often distinguishes mid-level and senior engineers, demonstrating their mature design skills.