Apple SDE 3 Interview Experience | Java Spring Boot

• Company: Apple

• Role: Software Development Engineer 3 (SDE 3)

• Tech Stack: Java, Spring Boot, Kafka, Redis

Round 1: Java Coding and Problem-Solving

In the first round, I was given a Java project containing approximately eight test cases. The task was to work through the test cases one by one, solve the associated problems, and explain the reasoning behind each solution.

The interviewer focused on how I approached the problems, the logic behind my implementation, and my ability to explain the decisions I made while working through the code.

Round 2: Kafka and System Design

The second round focused heavily on Apache Kafka and system design scenarios.

1. Kafka: What happens when the consumer goes down while the producer continues sending messages?

The interviewer presented a scenario in which a producer continues publishing messages, but the consumer is unavailable. As a result, messages accumulate in Kafka, and the interviewer asked how to handle the situation when the brokers have finite storage capacity.

The discussion revolved around handling consumer failures, managing message backlogs, and preventing storage exhaustion.

2. Design a Rate Limiter Using the Sliding Window Algorithm

I was also asked to design a rate limiter and explain how I would implement the sliding window algorithm.

I chose Redis for the implementation and discussed how it could be used to track requests within a time window and enforce rate limits efficiently.

This question tested my understanding of system design, algorithm selection, and the practical use of Redis in distributed applications.

After clearing the first two rounds, I progressed to Rounds 3, 4, and 5. I'm currently waiting for the next steps in the interview process and will share an update once I hear back from Apple.