Four Million Echoes

A medium ai_coding interview practice problem on DataDriven. Write and execute real ai_coding code with instant grading.

Domain

ai_coding

Difficulty

medium

Seniority

L5

Problem

Our orders enrichment consumer reprocesses ~4M messages every time we deploy. The team added enable_auto_commit=False and explicit commit() calls weeks ago, so this should have stopped. Run tests/test_offsets_persist.py to reproduce. The reprocess window correlates with rebalance events. Find why the explicit commits aren't sticking and fix it. Bonus credit: explain what 'cooperative-sticky' would have changed.

Summary

It happened. It happened again.

Practice This Problem

Solve this ai_coding problem with real code execution. DataDriven runs your solution and grades it automatically.