Why Deep Work on a Hard CI Bug Went Wrong and How a Clearer Approach Fixed It

A developer spent a long day and night chasing an elusive bug in a CI pipeline, losing track of their own exhaustion and pressure from their supervisor. The root cause turned out to be a backwards-incompatible update in a dependency of a dependency, which was resolved by pinning an older version. On a later occasion, the developer set expectations with their supervisor upfront and debugged by entering the Docker container interactively, which allowed faster testing of fixes. The author argues that the difference between the two experiences lay not in concentration but in awareness of their own state and situation. The account is presented as a reflection on deep work, especially relevant when coding agents parallelize tasks but cannot replace focused human attention.