Skip to content

Tracks Drills Topics Technologies Tech stacks Skill areas

Tracks Drills Topics

Loading

Aporeon

Technical interview practice, from one developer to another.

About Support Privacy Terms Refund policy

Python Backend Practical Labs

Focused Python implementation, debugging, code-review, integration, and production diagnosis exercises.

12 drillsPractice one at a timeOrdered pathCoding problem

Recommended start

Immutable Python money

Builds a frozen dataclass around Decimal with explicit scale, validation, arithmetic, ordering, and value equality.

Medium~25 minStep 1 of 12

Practice this drill Choose another

Search

12 of 12 shown

1Immutable Python moneyRecommended startBuilds a frozen dataclass around Decimal with explicit scale, validation, arithmetic, ordering, and value equality.Coding problemMedium~25 minPythonPractice 2Bounded async HTTP fetchesImplements bounded asyncio HTTP concurrency with one client, per-call deadlines, TaskGroup ownership, and deterministic cleanup.

Practice order

12 drillsOne at a time

1Immutable Python moneyUp next / Medium / ~25 min
2Bounded async HTTP fetchesHard / ~35 min
3Validated FastAPI createMedium / ~25 min

Coding problemHard~35 minPython

Practice

3Validated FastAPI createBuilds a FastAPI POST boundary with separate input/output models, forbidden extra fields, domain mapping, and a 201 response.Coding problemMedium~25 minFastAPIPydanticPythonPractice

4Persisted FastAPI idempotencyImplements a database-backed idempotency boundary that replays one response and rejects key reuse with a different request.Coding problemHard~35 minFastAPIPythonSQLAlchemyPractice

5FastAPI ownership testTests missing, unauthenticated, owner, and cross-owner access through FastAPI's real dependency and routing boundary.Coding problemMedium~25 minFastAPIpytestPythonPractice

6Django N+1 regressionRepairs a Django serialization path with select_related and prefetch_related, then locks the query shape with a regression test.Coding problemMedium~25 minDjangopytestPythonPractice

7Django inventory reservationUses a database transaction and row lock to keep stock non-negative when reservations race.Coding problemHard~35 minDjangoPythonPractice

8SQLAlchemy keyset pageBuilds descending keyset pagination with a unique tie-breaker, opaque cursor, limit-plus-one query, and stable next page.Coding problemHard~35 minPythonSQLAlchemyPractice

9SQLAlchemy version conflictUses SQLAlchemy version counters and an HTTP precondition to reject stale writes without silently overwriting newer state.Coding problemHard~35 minFastAPIPythonSQLAlchemyPractice

10SQLAlchemy order and outboxPersists business state and durable publication intent atomically while leaving broker delivery to an idempotent publisher.Coding problemHard~35 minPythonSQLAlchemyPractice

11pytest PostgreSQL constraintRuns a migration-backed pytest integration test against PostgreSQL and proves case-insensitive email uniqueness.Coding problemMedium~25 minAlembicpytestPythonPractice

12Reliable Celery provider taskBuilds a Celery task that survives timeout ambiguity, retries temporary failures, and records one durable business outcome.Coding problemHard~35 minPythonPractice

4

Persisted FastAPI idempotency

Hard / ~35 min

5FastAPI ownership testMedium / ~25 min

6Django N+1 regressionMedium / ~25 min

7Django inventory reservationHard / ~35 min

8SQLAlchemy keyset pageHard / ~35 min

+4 more drills in this section

Python Backend Practical Labs - Python Backend | Aporeon