Amazon SDE2 Interview Experience
Summary
I recently completed an Amazon SDE2 interview that covered coding, system design, and leadership principles rounds.
Full Experience
Recently interviewed for Amazon SDE2 role. Sharing the interview flow and questions asked.
Interview Process:
- Coding Round
- Managerial / Leadership Principles Round
- Hiring Manager Round (HLD focus)
Main focus areas:
- DSA
- Scalability
- Performance
- Customer Obsession
- Ownership
- STAR format answers
Round 1 - Coding + Project Discussion
Started with:
- Deep dive into projects
- Design decisions
- Tradeoffs
- Ownership-related questions
Coding Question:
Amazon receives transfer notifications whenever money moves between accounts.
Transfers form a chain, for example:
A → B → C → D
Input is provided as pairs:
[A, B] meaning money moved from A to B.
Task: Find:
- Initial source account
- Final destination account
Example:
numberOfTransfers = 3
transferList = [ (222, 111), (111, 333), (444, 222) ]
Output:
start = 444 end = 333
Explanation:
444 → 222 → 111 → 333
Main concepts:
- Graphs
- HashSet
- In-degree / out-degree style thinking
Round 2 - System Design (HLD)
Design Amazon Locker System
Requirements discussed:
- Delivery driver deposits package
- Customer receives code
- Customer unlocks locker using code
- Locker allocation
- OTP/code validation
- Expiry handling
- Multiple locker sizes
- Scalability
- Availability
- Failure handling
Topics interviewer focused on:
- API design
- Database schema
- Concurrency handling
- Distributed locking
- Scalability
- Performance optimization
- Notification flow
- State transitions
Managerial / Leadership Principles Round
Heavy focus on:
- Customer Obsession
- Ownership
Advice: Prepare STAR-format stories thoroughly.
Behavioral topics included:
- Production incidents
- Taking ownership
- Difficult decisions
- Handling ambiguity
- Conflict resolution
- Improving customer experience
Overall interview focus:
- Strong coding fundamentals
- Scalable system design
- Leadership principles
- Real-world engineering thinking
Hope this helps others preparing for Amazon SDE2 interviews.
Interview Questions (2)
Find start and end accounts in a transfer chain
Amazon receives transfer notifications whenever money moves between accounts. Transfers form a chain (e.g., A → B → C → D). Input is provided as pairs [A, B] meaning money moved from A to B. Task: Find the initial source account and the final destination account.
Example:
numberOfTransfers = 3
transferList = [
(222, 111),
(111, 333),
(444, 222)
]
Output: start = 444, end = 333
Explanation: 444 → 222 → 111 → 333
Main concepts: Graphs, HashSet, in‑degree/out‑degree thinking.
Design Amazon Locker System
Design a high‑level system for an Amazon Locker service.
Requirements:
- Delivery driver deposits a package.
- Customer receives a code.
- Customer unlocks locker using the code.
- Locker allocation, OTP/code validation, expiry handling.
- Support multiple locker sizes.
- Ensure scalability, high availability, and failure handling.
Focus areas for discussion: API design, database schema, concurrency handling, distributed locking, scalability, performance optimization, notification flow, and state transitions.
Preparation Tips
I focused on practicing STAR‑format behavioral stories and reviewed system design topics such as API design, database schema, concurrency, scalability, and performance optimization.