Crashguard is a self-hosted (LGPL3) canary-oriented monitoring system for asynchronous workflows — background jobs, cross-service pipelines, anything where "it should finish by X" matters more than any single log line. The model is simple: start a canary when a workflow kicks off, resolve it when the workflow finishes. If the canary doesn't resolve before its deadline, Crashguard fires an alert immediately — no log scraping, no complex alerting rules. Also comes with a stream deck XL+ plugin.