Senior backend interview simulator

quantlab turns backend practice into interview-ready proof.

Diagnose weak areas, get an adaptive coach plan, practice on production-style prompts, and see the scorecard that decides what to do next.

Guided loop

Readiness proof

Skill radar

quantlab turns lesson history, graded answers, hints, and review misses into a readable skill map.

Java concurrency

Strong

82%

PostgreSQL plans

Fragile

61%

Architecture trade-offs

Progressing

74%

Auth and sessions

Needs proof

48%

Current signal

4 fragile signals found

Each step leaves evidence that updates the map, FSRS queue, and next exercise.

Visitors see the exact skill evidence that drives the next lesson, not a generic course catalog.

Energy, focus, weak areas, and FSRS review decide the block size and difficulty.

Rubrics turn open-ended answers into readiness signals, review cards, and paid-product value.

Sample tracks

Collections, concurrency, JVM, GC, Spring, generics.

Query optimization, MVCC, transactions, partitioning.

DDD, CQRS, Event Sourcing, Clean Architecture, Sagas.

Application & infrastructure security: OWASP Top 10, auth pitfalls, secrets management, real-world incidents.