Django & FastAPI interview questions, explained.
API rounds check whether you can design endpoints other people can rely on: correct status codes, safe retries, sensible pagination and an ORM that does not fire a hundred queries per request.
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Readiness assessment
Know exactly where you stand in APIs & Web Frameworks.
- Overall readiness score out of 100
- Skill-wise breakdown across 7 areas
- Your gaps, ranked by priority
- An action plan and simple explanations for every miss
₹49
28 questions · 30 min · instant report
What interviewers check
Four things decide this round.
REST design
Resources, methods, status codes and idempotency.
Auth
Sessions versus JWT, token lifetimes and where to store secrets.
Performance
N+1 queries, select_related/prefetch_related and pagination at scale.
Async
When async helps in FastAPI and how blocking calls freeze the event loop.
Try before you pay
One question.
See how you think.
This is the style of every question in the assessment: real situations, not trivia, with an explanation for each answer. The full test covers 28 questions across 7 skills.
A client sends a signup request with the email field missing. What should the API return?
Invalid input is the client's fault, so it is a 4xx. FastAPI returns 422 for validation errors by default; many teams use 400. Returning 200 for errors breaks clients and monitoring.
· FreeMistakes that cost offers
- Returning 200 with an error message in the body.
- Calling blocking libraries inside async endpoints.
- Using OFFSET pagination on large, fast-changing tables.
How to practise
Design clean REST APIs: correct status codes, idempotency, pagination, auth (JWT/sessions) and avoiding N+1 queries in Django/FastAPI.
- Build a FastAPI or Django REST service with auth, pagination and validation.
- Profile an endpoint with django-debug-toolbar and remove N+1 queries.
- Add async endpoints and keep blocking calls off the event loop.
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30-min test
Job Readiness Assessment
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One-time payment · Python / AI Backend Engineer
What you get
- Role-specific readiness assessment (28 questions, 30 min)
- Overall readiness score and skill-wise breakdown
- Strengths and skill gaps across 7 core areas
- Personalised assessment report with answer explanations
How it works
- 1 Unlock it at checkout
- 2 Take the 28-question test (30 min)
- 3 Get your report instantly
Best for: Candidates who want to know exactly where they stand.
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Assessment + Personal Guidance
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₹99 assessment + ₹500 for a 30-minute one-to-one session
What you get
- Everything in the ₹99 assessment
- One-to-one review of your assessment results
- Identify your highest-priority skill gaps
- Guidance on what to learn and practise next
- Personalised next-step action plan
How it works
- 1 Pay ₹599 securely
- 2 Take the test and get your report
- 3 Review it one-to-one on Google Meet
Best for: Candidates who want a clear improvement roadmap.
Mentoring is guidance to help you improve, not a job guarantee.
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Personal Mentoring
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60-minute one-to-one session · No assessment required
What you get
- Deep-dive on your career and technical challenges
- Detailed review of your Python / backend skills and projects
- Interview preparation priorities and mock questions
- Written, personalised action plan after the session
How it works
- 1 Pay ₹999 securely
- 2 Pick a 60-minute slot
- 3 Meet on Google Meet, get a written plan
Best for: Candidates who already know what they need help with.
Mentoring is guidance to help you improve, not a job guarantee.
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Your mentor
Nagendra Kumar
IIT Delhi graduate · 10+ years
300+
engineers interviewed
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