Backend Developer Interview Prep — for engineers in Tashkent and Central Asia

Core skills tested

• One server-side language deeply (Java, Go, Python, Node.js, or .NET)
• SQL fluency: joins, indexes, query plans, transaction isolation
• HTTP, REST, gRPC, and when to choose each
• Caching strategies (in-memory, Redis, CDN)
• Concurrency primitives (threads, async, channels, mutexes)
• Authentication, authorization, JWT pitfalls
• Observability: structured logs, metrics, tracing
• Reading and reviewing other engineers' code

Salary ranges in Tashkent (2026)

Approximate. Remote-first European roles typically pay 30–50% above local rates.

What you will actually be asked

Pulled from real interviews recorded on NextSuhbat. Each item is a question you should expect, plus what the interviewer is really testing.

1. 1

   Recruiter screen

   Walk me through the most complex API you have shipped to production.

   Why it is asked: Tests communication and your sense of scope. Two minutes — what the API does, why it was hard, what the metric was.

2. 2

   Technical

   Explain the difference between SQL and NoSQL, and when you would pick each.

   Why it is asked: Tests whether you have a real opinion. Strong answers cite consistency vs. partition tolerance, schema rigidity, query patterns.

3. 3

   Technical

   What does database indexing do, and what is the cost?

   Why it is asked: Tests if you know indexes speed reads and slow writes. Bonus for B-tree vs. hash vs. composite, covering indexes.

4. 4

   Technical

   Walk me through what happens when a client makes an HTTP request to your service.

   Why it is asked: TCP handshake, TLS, request parsing, routing, middleware, handler, DB query, response. Do not skip TLS.

5. 5

   Technical

   Explain transaction isolation levels — read uncommitted, read committed, repeatable read, serializable.

   Why it is asked: Senior bar. Tie each level to a real anomaly (dirty read, non-repeatable read, phantom read).

6. 6

   Coding

   Implement a rate limiter that allows N requests per user per minute.

   Why it is asked: Tests data structures (sliding window, token bucket), thread-safety, and how you reason about tradeoffs.

7. 7

   Coding

   Given an unsorted array of integers, return the K most frequent elements.

   Why it is asked: Heap-based solution beats brute-force sort. Tests both algorithm choice and clean implementation.

8. 8

   System design

   Design a URL shortener like bit.ly that handles 100M URLs and 1B redirects per month.

   Why it is asked: Classic. Cover ID generation, storage, caching, analytics. Talk through capacity numbers, do not skip them.

9. 9

   Behavioral

   Tell me about a time you made a tradeoff between speed and code quality.

   Why it is asked: Pick a story where the tradeoff was deliberate, not lazy. Mention what you would do differently with hindsight.

10. 10

    Behavioral

    Tell me about a production incident you led the response on.

    Why it is asked: Wrong answer: "we never had incidents." Right: 90-second story with timeline, root cause, and a follow-up change.