← Amazon Interview Insights

Amazon·Software Engineer·Onsite - System Design / Architecture·Senior

Senior
Jun 2026

Summary

Interviewed for a solutions architect role at Amazon and got hit with a classic system design question about three-tier architecture. Short session, not much fluff.

Questions Asked (1)

Q1

How would you design a three-tier architecture?

System DesignTechnical Trade-offs
Author's notes

I knew this one cold, or thought I did.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and constraints, then walk through each tier (presentation, logic, data) explaining their responsibilities, interactions, and the trade-offs involved. Emphasize scalability, availability, and security, and tie your choices back to Amazon's leadership principles and AWS services.

Pro tip: Show how you would evolve the architecture over time, starting simple and adding complexity only when needed, and discuss how you would monitor and test each tier independently.

1. Clarify Requirements

Ask about expected scale, latency, consistency, and budget to tailor the design. This ensures you address the interviewer's specific concerns.

2. Define Tiers and Responsibilities

Describe the presentation tier (UI), logic tier (business rules), and data tier (storage), and what each should handle. Explain how they communicate via well-defined APIs.

3. Choose Technologies and Patterns

Select appropriate technologies (e.g., React for UI, Node.js for logic, DynamoDB for data) and patterns (e.g., REST, caching, load balancing). Justify choices with trade-offs.

4. Address Cross-Cutting Concerns

Discuss scalability (horizontal scaling, auto-scaling), availability (multi-AZ, redundancy), security (auth, encryption), and monitoring (logging, metrics).

5. Summarize and Iterate

Recap the design, highlight how it meets requirements, and suggest potential improvements or next steps. Invite feedback.

Key Points to Mention

  • Separation of concerns and loose coupling between tiers
  • Scalability strategies: horizontal scaling, load balancing, caching
  • High availability: redundancy, failover, multi-AZ deployments
  • Security: authentication, authorization, encryption in transit and at rest
  • Trade-offs: consistency vs. availability, latency vs. cost, monolith vs. microservices
  • AWS services: EC2, ELB, RDS, DynamoDB, S3, CloudFront, API Gateway

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.