Company interview vault

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

#2581

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

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

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

#2582

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

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

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

#2583

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

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

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Instacart Mid-level (3–5 years) Behavioral

#2584

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

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

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

#2585

Compare ACID and BASE consistency models in databases — Instacart interview

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

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

#2586

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

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

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

#2587

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

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

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

#2588

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

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

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

#2589

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

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

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

#2590

How does HashMap work internally in Java? — Instacart interview

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

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

#2591

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

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

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

#2592

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

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

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

#2593

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

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

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

#2594

What principles do you follow when designing RESTful APIs? — Instacart interview

Reported in Instacart USA engineering loops. API design question covering resources, HTTP semantics, and versioning.

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Instacart Mid-level (3–5 years) Behavioral

#2595

Tell me about a time you disagreed with a teammate. How did you handle it? — Instacart interview

Reported in Instacart USA engineering loops. Behavioral STAR question assessing collaboration and conflict resolution.

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