Healthchecks.io

Healthchecks.io launched as a focused cron monitoring service: your job checks in on schedule; if it misses, you get paged. Caune’s about page is explicit — do one thing well, respect privacy, keep the stack boring.

Early on it was a one-person company (SIA Monkey See Monkey Do) built on Django and PostgreSQL — the kind of stack you can debug alone at midnight without paging a platform team.

Since 2017 the service runs on dedicated Hetzner boxes in Falkenstein — HAProxy terminating TLS, Django via uWSGI on app servers, PostgreSQL with streaming replication and manual failover. A small Go service (hchk) handles the high-volume ping API and inbound email.

Caune’s 2022 hosting post reads like a sysadmin zine: WireGuard between tiers so HAProxy cannot talk to Postgres directly, daily encrypted backups to S3, Fabric deploy scripts. No Kubernetes — just systemd, nginx rate limits, and a Yubikey backpack for emergencies.

The about page publishes open metrics updated manually: eleven years in business, hundreds of thousands of checks, tens of millions of pings processed daily — profitable and sustainable on hardware with healthy excess capacity.

Caune donates 5% of MRR to open-source dependencies and keeps the codebase BSD-licensed on GitHub. The lesson for indie hackers: a niche reliability tool can fund one life on metal you can reboot yourself.