Amazon SDE-2 with 3 years experience — DSA, LLD, HLD, Bar Raiser

## Background
The process opened with an OA covering DSA, behavioural questions and a system design component. After clearing it I moved into four loop rounds, a mix of in-person and virtual.

## Round-by-round

### Round 1 — Coding / DSA
Fairly standard territory — graphs, DP, arrays and strings. The interviewer wanted more than a working solution: it had to be syntactically clean, and I had to handle follow-up constraints added as the conversation went on.

### Round 2 — Low-level design
Requirement gathering, then API design and schema design. Doing well came down to solid OOP fundamentals and the right design patterns, backed by class and UML diagrams.

### Round 3 — High-level design & hiring manager
Define requirements up front, then estimate scale — expected users, queries per second, database size — and justify every design decision, including caching strategy and the overall logical flow.

### Round 4 — Bar Raiser
Conducted by someone from a completely different team, evaluating performance holistically. A mix of HLD, LLD and DSA, and I was expected to produce fully functional, tested code rather than pseudocode.

## A note on Leadership Principles
These weren't confined to one round — one or two came up in every session, always tied back to real experiences from my background.

## Verdict
**Selected.**