Microsoft L62 Interview Experience | Ireland
Summary
I completed four interview rounds (coding, low‑level design, high‑level design, and managerial) for a Software Engineer position at Microsoft in Ireland and was selected.
Full Experience
Sharing my recent Microsoft Software Engineer interview experience. The process consisted of 4 rounds, with each round being approximately 45 minutes.
Background
- Currently Laid off
- 5 YOE, Worked in Product Based MNC (FAANG)
Round 1 — Coding / Problem Solving
- The first round was a coding round and was eliminatory.
The question was to design an Expression Evaluator.
Given a mathematical expression containing:
+, -, *, /
Parentheses
Multi-digit integers
Spaces
Unary + / -
The evaluator had to return the integer result while respecting standard operator precedence.
Example
-7 + 5 * 8 - 5 / 4 + (5 + 4)
The main focus was on:
Parsing the expression
Operator precedence
Handling nested parentheses
Handling unary operators
Multi-digit numbers
Edge cases
This round was eliminatory, so getting to a correct approach was important.
Round 2 — Low-Level Design
The second round was an LLD round.
Problem: Design a Library Management System
The discussion covered:
Identifying the core entities Defining classes and their responsibilities Relationships between entities Borrowing and returning books Handling different types of users/books Extensibility of the design Implementation-level decisions
The interviewer went beyond just drawing a class diagram and discussed how the system would actually be implemented.
Round 3 — High-Level Design
The third round was a System Design / HLD round.
Problem: Design an E-commerce Shopping System
The requirements included:
Product search, filtering and sorting Viewing product details Purchasing products Secure checkout Integration with an existing Inventory Management System through APIs Scale
The following scale assumptions were provided:
10M products 1M users/day ~11 requests/sec 10K orders/hour ~2.5 orders/sec 5–10 products per order
The discussion covered the overall architecture, APIs, data storage, product search, inventory integration, checkout flow, scalability, and other system-design considerations.
Round 4 — Managerial / Resume Discussion
The final round was primarily a managerial round.
The discussion included:
Resume walkthrough Previous projects and experience Technical decisions made in previous roles Behavioral and managerial questions Follow-up questions based on my experience
There was also a short system-design discussion toward the end.
VERDICT: SELECTED.
Interview Questions (3)
Expression Evaluator
The question was to design an Expression Evaluator. Given a mathematical expression containing:
- +, -, *, /
- Parentheses
- Multi-digit integers
- Spaces
- Unary + / -
The evaluator had to return the integer result while respecting standard operator precedence.
Example: -7 + 5 * 8 - 5 / 4 + (5 + 4)
The main focus was on:
- Parsing the expression
- Operator precedence
- Handling nested parentheses
- Handling unary operators
- Multi-digit numbers
- Edge cases
Library Management System Design
Problem: Design a Library Management System. The discussion covered:
- Identifying the core entities
- Defining classes and their responsibilities
- Relationships between entities
- Borrowing and returning books
- Handling different types of users/books
- Extensibility of the design
- Implementation-level decisions
E‑commerce Shopping System Design
Problem: Design an E‑commerce Shopping System. Requirements included:
- Product search, filtering and sorting
- Viewing product details
- Purchasing products
- Secure checkout
- Integration with an existing Inventory Management System through APIs
- Scale assumptions: 10M products, 1M users/day, ~11 requests/sec, 10K orders/hour, ~2.5 orders/sec, 5–10 products per order The discussion covered overall architecture, APIs, data storage, product search, inventory integration, checkout flow, scalability, and other system‑design considerations.