https://illari.dev/blog Notes on monitoring scheduled jobs. en https://illari.dev/blog/the-pipeline-that-got-slower-every-week https://illari.dev/blog/the-pipeline-that-got-slower-every-week Sun, 27 Sep 2026 12:00:00 GMT Four minutes in January, forty in April, a clean exit every night in between. Why gradual slowdown hides from monitoring, how to record run duration where a trend is visible, and how to alert on slower-than-usual. https://illari.dev/blog/cron-monitoring-without-a-dedicated-tool https://illari.dev/blog/cron-monitoring-without-a-dedicated-tool Mon, 21 Sep 2026 12:00:00 GMT What PagerDuty, Opsgenie, and Sentry Crons actually do out of the box for a missed cron job, and where each one falls short of a dedicated monitor: pricing, native detection, alert gating, and Opsgenie's sunset date. https://illari.dev/blog/keep-cron-monitoring-in-the-same-repo https://illari.dev/blog/keep-cron-monitoring-in-the-same-repo Wed, 16 Sep 2026 12:00:00 GMT Monitoring that lives in a dashboard drifts away from the jobs it watches: new jobs ship without a monitor, and changed jobs keep a stale one. Define the monitor as code, next to the schedule. https://illari.dev/blog/your-ai-agent-can-finish-clean-and-still-be-wrong https://illari.dev/blog/your-ai-agent-can-finish-clean-and-still-be-wrong Thu, 03 Sep 2026 12:00:00 GMT An agent can post a confident summary and still have updated nothing, run out of turns mid-task, or burned the budget for no result. What to measure so the run's own numbers tell you. https://illari.dev/blog/dbt-tests-without-a-data-observability-platform https://illari.dev/blog/dbt-tests-without-a-data-observability-platform Tue, 01 Sep 2026 12:00:00 GMT dbt already has tests and source freshness. What they cover, where they stop, and how to get a scheduled dbt build to page you when a test fails or the run goes missing, without adopting a profiling platform. https://illari.dev/blog/airflow-dag-succeeded-but-the-table-is-stale https://illari.dev/blog/airflow-dag-succeeded-but-the-table-is-stale Mon, 31 Aug 2026 12:00:00 GMT Every task in the DAG is green, and the model it builds hasn't updated since Tuesday. Why Airflow's success is orthogonal to data freshness, and how to check freshness without a data-observability platform. https://illari.dev/blog/catching-the-pipeline-that-processed-zero-rows https://illari.dev/blog/catching-the-pipeline-that-processed-zero-rows Fri, 28 Aug 2026 12:00:00 GMT A dbt build, an Airflow DAG, or a plain cron ETL can finish green and load nothing. How to make a zero-row run a failed run, without a data-observability platform. https://illari.dev/blog/scheduled-job-monitoring-tools-compared https://illari.dev/blog/scheduled-job-monitoring-tools-compared Fri, 21 Aug 2026 12:00:00 GMT A comparison of the main heartbeat monitoring services for scheduled jobs, workers, and agent runs: pricing models, free tiers, self-hosting, whether they check the run or just the check-in, and where each one fits. https://illari.dev/blog/exit-code-0-but-the-backup-was-empty https://illari.dev/blog/exit-code-0-but-the-backup-was-empty Fri, 17 Jul 2026 12:00:00 GMT A job can finish with exit code 0 and still have done the wrong thing: an empty dump, a partial sync, a half-written report. How to catch the runs that succeed on paper. https://illari.dev/blog/how-to-know-if-your-cron-job-silently-failed https://illari.dev/blog/how-to-know-if-your-cron-job-silently-failed Fri, 12 Jun 2026 12:00:00 GMT Cron won't tell you when a job stops running. Here's why scheduled jobs fail silently, and the practical ways to find out before it costs you. https://illari.dev/blog/cron-timezones-and-daylight-saving https://illari.dev/blog/cron-timezones-and-daylight-saving Wed, 08 Apr 2026 12:00:00 GMT Cron runs in the system timezone. What that means at the spring-forward and fall-back transitions, how CRON_TZ and systemd timers change it, and why UTC is the safe default for scheduled jobs. https://illari.dev/blog/cron-expression-syntax https://illari.dev/blog/cron-expression-syntax Wed, 21 Jan 2026 12:00:00 GMT The five fields, what each one accepts, the operators (* , - /), the day-of-month vs day-of-week trap, the @macros, and where other tools' cron dialects differ. With worked examples. https://illari.dev/blog/a-brief-history-of-cron https://illari.dev/blog/a-brief-history-of-cron Tue, 14 Oct 2025 12:00:00 GMT Cron has scheduled Unix jobs since 1975. How it went from a single system table read once a minute to Vixie cron, cronie, systemd timers, and Kubernetes, and why the crontab format has barely changed.