Engineering blog
How-to guides on watching servers, databases, logs, certificates and APIs. Written by the people building Vigil; every guide works on the free plan.
The London outage of 20 October 2026: nine status pages, one Google Cloud zone
A power event in Google Cloud's europe-west2-b zone hit Kinsta, Aiven, Elastic Cloud, Cloudways, MongoDB Atlas, ClickHouse Cloud, CockroachDB and Confluent. When each status page posted, what Vigil could and could not see, and the single-region lesson.
How to monitor PostgreSQL connections, cache hit ratio and replication lag (and get paged before it hurts)
The four PostgreSQL numbers that predict an outage, the SQL to read them, sensible thresholds, and how to alert on them without installing an exporter.
See every API your server calls (and every call it receives) without changing a line of code
How passive HTTP capture on a Linux host works with AF_PACKET and a BPF filter, what it can and cannot see with TLS, and how to turn it into per-endpoint latency, error rates and a service map.
Self-hosting a full monitoring stack in one command: servers, logs, APM and status pages
What it takes to run your own observability stack, why the usual Prometheus + Grafana + Loki route costs more time than money, and how a one-command Docker install with signed releases works.
Get alerted before an SSL certificate expires (the three checks that actually matter)
Certificates still expire in production every week. Here is how to check expiry, chain and hostname from the shell, why auto-renewal fails silently, and how to get a warning 14 days out.