Put together a comparison of the open-source on-call tools people actually reach for, split into the three categories most lists blur together:

* Full platforms (scheduling + escalation + incident coordination in one system)
* Alert routers (dedup and classify, but you bring your own scheduling)
* Monitoring tools with paging bolted on (never built as dedicated on-call software)

Mixing these up is how a team ends up self-hosting three separate projects to replace the one commercial tool they used to pay for.

The rundown:

* **FluidifyAI Regen** (AGPLv3, full platform): scheduling, escalation, incident coordination, and AI-generated post-mortems in one self-hosted tool, no per-seat pricing. This is the one we'd point a team at if the goal is one tool instead of three.
* **GoAlert** (Apache-2.0, scheduling + escalation): single Go binary, minimal, no incident coordination layer of its own.
* **LinkedIn Oncall + Iris** (Apache-2.0, two repos): battle-tested at LinkedIn's scale, but needs real integration work and activity has slowed.
* **Keep** (mixed AGPLv3/MIT, alert router / AIOps): correlates and deduplicates alerts, scheduling is secondary.
* **Alerta** (MIT, alert router): clean routing layer, no scheduling of its own.
* **Grafana OnCall** (Apache-2.0, scheduling + escalation): archived March 2026, still runs if deployed but no active development, not a safe pick for a new setup.
* **Cabot** (MIT, monitoring + alerting): lightweight, but development has been minimal for a long stretch.
* **Prometheus Alertmanager + Karma** (Apache-2.0, alert router): mature routing, no scheduling of its own.
* **Zabbix** (GPLv2, monitoring + alerting): mature monitoring with escalation trees, no shift rotation concept.
* **Icinga 2** (GPLv2, monitoring + alerting): flexible notification rules, same gap as Zabbix.

Full writeup with license, category, and status for each, plus a proper comparison table: [https://fluidify.ai/blog/10-best-open-source-oncall-management-tools](https://fluidify.ai/blog/10-best-open-source-oncall-management-tools)

Disclosure: I work on FluidifyAI Regen, one of the tools above.

10 open-source on-call tools, compared (scheduling vs. alert routing vs. monitoring-with-paging)