Developer embeds ETL failure signals directly into output files after 71-day data blind spot

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A developer discovered their Reddit scraper had been returning empty arrays silently for 71 days, with no visible pipeline errors to flag the issue. The problem only surfaced when a downstream interpretation layer noticed Reddit-sourced signals had not changed in roughly two months. To prevent recurrence, three failure-reporting patterns were added directly into the daily output JSON artifact, including a per-source health boolean, a structured error array with timestamps, and a pipeline monitor that opens a GitHub issue when any source fails. Unlike runner logs that are rarely checked unless a problem is already suspected, the artifact is read on every downstream pass, making failures visible in git diffs and health checks. The interpretation layer is also now fail-closed, ignoring data from any source flagged as unhealthy rather than silently mixing bad data into weekly aggregates.

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ProgrammingDEV Community ·

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