Company interview vault

Microsoft Mid-level (3–5 years) Coding / DSA

#3196

Design and implement an LRU cache with O(1) get and put — Microsoft interview

Reported in Microsoft USA engineering loops. Hash map plus doubly linked list problem bridging DSA and system components.

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Microsoft Mid-level (3–5 years) Coding / DSA

#3197

How many distinct ways can you climb n stairs taking 1 or 2 steps at a time? — Microsoft interview

Reported in Microsoft USA engineering loops. Introductory dynamic programming problem isomorphic to Fibonacci.

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Amazon Mid-level (3–5 years) Coding / DSA

#3198

How do you perform topological sort on a directed acyclic graph? — Amazon interview

Reported in Amazon USA engineering loops. Graph algorithm for task scheduling, build systems, and course prerequisites.

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Amazon Mid-level (3–5 years) Technical deep dive

#3199

What is dependency injection and why is it useful? — Amazon interview

Reported in Amazon USA engineering loops. Java/Spring staple connecting OOP design to testable service architecture.

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Amazon Mid-level (3–5 years) Technical deep dive

#3200

How do you version a public API without breaking clients? — Amazon interview

Reported in Amazon USA engineering loops. API evolution question covering compatibility, deprecation, and communication.

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Amazon Mid-level (3–5 years) Behavioral

#3201

Tell me about a project that failed or missed its deadline. What did you learn? — Amazon interview

Reported in Amazon USA engineering loops. Behavioral question testing accountability, retrospectives, and growth.

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Amazon Mid-level (3–5 years) Technical deep dive

#3202

Compare ACID and BASE consistency models in databases — Amazon interview

Reported in Amazon USA engineering loops. Distributed data question bridging SQL transactions and NoSQL eventual consistency.

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Amazon Mid-level (3–5 years) Technical deep dive

#3203

How does Node.js handle concurrent requests with a single thread? — Amazon interview

Reported in Amazon USA engineering loops. Node.js architecture question on libuv, event loop phases, and worker threads.

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Amazon Mid-level (3–5 years) Technical deep dive

#3204

When would you use useState versus useReducer in React? — Amazon interview

Reported in Amazon USA engineering loops. React hooks question on local state complexity and predictable updates.

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Amazon Mid-level (3–5 years) Technical deep dive

#3205

What is the Python GIL and how does it affect concurrency? — Amazon interview

Reported in Amazon USA engineering loops. Python-specific question on threading limits and multiprocessing alternatives.

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Amazon Mid-level (3–5 years) Technical deep dive

#3206

Explain the JavaScript event loop, call stack, and task queues — Amazon interview

Reported in Amazon USA engineering loops. Core JavaScript concurrency model question for frontend and Node.js roles.

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Amazon Mid-level (3–5 years) Technical deep dive

#3207

How does HashMap work internally in Java? — Amazon interview

Reported in Amazon USA engineering loops. Java-specific collections question on buckets, hashing, and resize behavior.

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Amazon Mid-level (3–5 years) Technical deep dive

#3208

What is the difference between unit and integration tests? — Amazon interview

Reported in Amazon USA engineering loops. Testing strategy question covering pyramid, mocks, and confidence vs speed.

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Amazon Mid-level (3–5 years) Technical deep dive

#3209

Explain CI/CD and what a typical pipeline includes — Amazon interview

Reported in Amazon USA engineering loops. DevOps fundamentals for mid-level engineers discussing automation and quality gates.

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Amazon Mid-level (3–5 years) Technical deep dive

#3210

When would you choose microservices over a monolith? — Amazon interview

Reported in Amazon USA engineering loops. Architecture trade-off question for mid-level backend and platform roles.

Medium Read answer →