I recently went through the interview process for a Engineer II role at American Express and wanted to share my experience. I hope it helps someone preparing for similar roles.

📌 Background:
Experience: 2 Years
Current Role: Software Engineer at a food-tech startup
Applied via: Referral

🧪 Interview Rounds (Total: 3 Rounds)
✅ Round 1: Technical Round (Java + DSA + System Basics)
Panel: 2 Interviewers

Topics Covered:

In-depth questions on Java, Spring Boot, Kafka, and GCP.
Focus on real-world usage of frameworks and deployment practices.

DSA Questions:

1. Modified Celebrity Problem (Using Stack)
   A variation that involved some twist around multiple potential candidates.

2. Fruit Into Baskets (Sliding Window)
   Classic problem from LeetCode (link: https://leetcode.com/problems/fruit-into-baskets/)

✅ Round 2: System Design + Project Discussion
Type: Deep dive discussion round

Focus Area:

• My current and past projects: design decisions, trade-offs, and scaling strategies.
• Detailed discussion on Payment Gateway Design – including retries, failure handling, idempotency, and third-party integrations.
• Interviewer was more interested in why I made certain design choices over alternatives.

✅ Round 3: Hiring Manager Round
Type: Face-to-Face (Behavioral + Tech)

Discussion Areas:

• My overall experience, contributions, and tech stack.
• Some sequence-based logical reasoning question (non-coding).
• Final 20 minutes were focused on behavioral questions, including:
  Handling disagreements in a team.
  Meeting tight deadlines.
  Seeking help and learning from failures.