Software Development Engineer, Amazon MWAA

Amazon

Write a program that prints the numbers from 1 to 100. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”. Details: Your solution should be runnable and demonstrate the output. Focus on clean, readable code. Consider edge cases and error handling (though not strictly required for this basic version). Provide a brief explanation of your approach and any assumptions you made. Example: 1 2 Fizz 4 Buzz Fizz 7 8 Fizz Buzz 11 Fizz 13 14 FizzBuzz ... Variations (optional, for a more challenging exercise): Allow the user to input the upper limit of the range (instead of always going to 100). Allow the user to input the numbers to use for Fizz and Buzz (instead of always using 3 and 5). Allow the user to input the words to use for Fizz and Buzz (instead of always using Fizz and Buzz). Handle invalid inputs gracefully. This question assesses a candidate's basic programming skills, understanding of loops and conditional statements, and ability to write clean, understandable code. The variations allow for exploring error handling, input validation, and more flexible program design.

Amazon

Let's dive into a debugging scenario. Imagine you are working on a critical e-commerce platform used by millions of customers. During a peak shopping period (like Black Friday), you receive alerts indicating a significant slowdown in the checkout process. Customers are reporting that it takes an unusually long time to complete their purchases, and some are even experiencing transaction failures. This is directly impacting sales and customer satisfaction. Your team suspects a performance bottleneck somewhere in the system. The architecture involves multiple microservices, including a user authentication service, a product catalog service, an inventory service, a payment processing service, and an order management service. These services communicate with each other via REST APIs and message queues. The database consists of both relational (PostgreSQL) and NoSQL (Redis) databases. You have access to logging, monitoring tools (like Prometheus and Grafana), and distributed tracing (like Jaeger). How would you approach debugging this issue systematically, identify the root cause, and propose a solution? Be specific about the tools and techniques you would use at each stage. For example, walk me through what metrics you'd focus on, how you would narrow down the problematic service, and what steps you'd take to pinpoint the exact code or configuration causing the bottleneck. Provide specific examples of commands or queries you might use to gather data or test hypotheses. Also consider potential causes related to scaling, caching, database performance, and code inefficiencies. How would you ensure minimal disruption to the platform during the debugging process? How do you handle conflicting information or dead ends during debugging?

Amazon

Describe a time when a plan did not go as expected.