Practice following one request and one failure across the whole system. If you can name ownership, limits, timeouts, and recovery at each boundary, your answers become concrete.
Method
How we chose
RecallDeck publishes this selection. When we recommend RecallDeck, we recommend our own product. There are no paid or affiliate placements. Tools earn a place by solving a distinct part of the target interview workflow; order is not a universal score.
- Authoritative protocol and database references
- Coverage of both implementation details and distributed trade-offs
- Practice material that requires assumptions, sizing, and failure analysis
- A path from conceptual recall to live coding and architecture explanation
Recommendations
The shortlist
MDN HTTP guides
Best for http semantics, caching, headers, and browser–server behavior
A precise HTTP model improves API design answers and prevents vague claims about methods, status codes, cookies, and caches.
PostgreSQL documentation
Best for transactions, indexes, concurrency, and query behavior
The official manuals provide the depth needed to reason about isolation, locks, plans, and schema choices.
System Design Primer
Best for a broad map of scalability patterns and prompts
Use the open-source outline to identify missing concepts and to seed timed design practice.
RecallDeck backend track
Best for retrieval across apis, storage, distributed systems, and reliability
Scheduled question practice makes it easier to produce precise explanations when an interviewer jumps between layers.
Put it to work
A practical workflow
- 1
Trace one API request through authentication, business logic, storage, and response caching.
- 2
Add a failure: a slow dependency, duplicate message, partial transaction, or overloaded pool.
- 3
Explain the observable signal, containment mechanism, and recovery path.
- 4
Implement one small concurrency or data-access task in the target language.
Quick answers
Frequently asked questions
What topics are asked in backend interviews?
Expect APIs and HTTP, authentication, SQL and data modeling, transactions, caching, queues, concurrency, distributed systems, testing, observability, reliability, and a language-specific coding round.
How should a senior backend engineer prepare?
Spend less time on definitions and more on trade-offs, failure modes, migration plans, operational limits, and evidence from systems you have owned.
Source notes
References and review policy
Source links provide further reading. Where a recorded technical review is available, the answer shows its date and scope. Tool selections use direct provider links and contain no affiliate placements. Sources, features, and hiring formats can change.
From reading to recall
Practice the full interview loop.
RecallDeck schedules the concepts you miss and keeps coding, design, and behavioral fundamentals available when the interviewer changes direction.