The symptom For four Mondays in a row my data pipeline finished with complete , stages_ok: 16 , stages_failed: 0 . And the run row in the database stayed empty: duration_ms was NULL, no summary written. Every downstream reader filters on duration_ms IS NOT NULL , sensibly, to skip fragmented runs. So those runs did not show up as broken. They did not show up at all. The public time series just had holes in it, and nothing anywhere used the word error. The only clue was in a later...