A streaming job counts billable ad impressions

A medium Pipeline Design interview practice problem on DataDriven. Write and execute real pipeline design code with instant grading.

Domain

Pipeline Design

Difficulty

medium

Problem

A streaming job counts billable ad impressions. When the job restarts it replays from the last offset and double-counts impressions, inflating revenue. Design the path so each impression counts exactly once even across restarts.

Practice This Problem

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