Company interview vault

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

#841

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

Reported in Back Market European engineering loops. React hooks question on local state complexity and predictable updates.

Medium Read answer →

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

#842

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

Reported in Back Market European engineering loops. Python-specific question on threading limits and multiprocessing alternatives.

Medium Read answer →

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

#843

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

Reported in Back Market European engineering loops. Core JavaScript concurrency model question for frontend and Node.js roles.

Medium Read answer →

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

#844

How does HashMap work internally in Java? — Back Market interview

Reported in Back Market European engineering loops. Java-specific collections question on buckets, hashing, and resize behavior.

Medium Read answer →

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

#845

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

Reported in Back Market European engineering loops. Testing strategy question covering pyramid, mocks, and confidence vs speed.

Easy Read answer →

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

#846

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

Reported in Back Market European engineering loops. DevOps fundamentals for mid-level engineers discussing automation and quality gates.

Medium Read answer →

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

#847

When would you choose microservices over a monolith? — Back Market interview

Reported in Back Market European engineering loops. Architecture trade-off question for mid-level backend and platform roles.

Medium Read answer →

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

#848

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

Reported in Back Market European engineering loops. API design question covering resources, HTTP semantics, and versioning.

Medium Read answer →

Back Market Mid-level (3–5 years) Behavioral

#849

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

Reported in Back Market European engineering loops. Behavioral STAR question assessing collaboration and conflict resolution.

Medium Read answer →

Back Market Mid-level (3–5 years) System design

#850

Design a distributed rate limiter for an API gateway — Back Market interview

Reported in Back Market European engineering loops. System design testing token bucket, sliding window, and Redis coordination.

Medium Read answer →

Back Market Mid-level (3–5 years) System design

#851

Design a URL shortening service — Back Market interview

Reported in Back Market European engineering loops. Foundational system design covering APIs, encoding, storage, and read-heavy scaling.

Medium Read answer →

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

#852

Explain and implement Dijkstra's algorithm for shortest paths — Back Market interview

Reported in Back Market European engineering loops. Graph algorithm for non-negative edge weights using priority queue.

Hard Read answer →

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

#853

Solve the 0/1 knapsack problem with dynamic programming — Back Market interview

Reported in Back Market European engineering loops. Classic DP testing tabulation, space optimization, and item selection reconstruction.

Hard Read answer →

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

#854

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

Reported in Back Market European engineering loops. Hash map plus doubly linked list problem bridging DSA and system components.

Hard Read answer →

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

#855

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

Reported in Back Market European engineering loops. Introductory dynamic programming problem isomorphic to Fibonacci.

Medium Read answer →