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About this interview
A technical interview on Low-Level Design and Object-Oriented Design, pitched at the medium level. A voice AI interviewer leads the conversation, adapts its questions to your answers, keeps you on topic, and afterward gives you honest, specific feedback on where you were strong and where to improve. Expect roughly 30 minutes.
What you'll be assessed on
Identify and apply relevant GoF design patterns (Strategy, Observer, Factory, Decorator, Command) to LLD problems
Produce a class model with correct relationships for a bounded domain such as a parking lot or vending machine
Design concurrency-safe in-memory systems such as a cache, message queue, or scheduler
Apply SOLID principles to keep class designs open for extension and easy to test
Topics covered
LLD FundamentalsOOP PrinciplesSOLID PrinciplesOOP DesignDesign PatternsClass ModelingConcurrency-Safe SystemsDesign Patterns Applied
A few sample questions
Just examples to set expectations - the real interview has many more and adapts to your responses.
“Can you walk me through what low-level design actually means in an interview context, and how it's different from the high-level system design interviews you might also encounter?
“Let's say you're designing a parking lot system. Talk me through the main classes you'd define, the relationships between them, and what enumerations or state machines you'd use.
“Walk me through how you'd model a hotel booking system at the class level. Focus on rooms, reservations, pricing strategies, and how you'd handle overbooking or cancellation policies.