Uptime

Nagios-descended infrastructure monitoring with auto-discovery, pre-built service checks, and a polished web UI. Raw edition is GPL-2.0.

GPL-2.0 · Python · ★ 2500 · Fresh

YAML-configured uptime monitoring with rich assertion DSL. Git-ops friendly.

Apache-2.0 · Go · ★ 7000 · Fresh

Cron-job and heartbeat monitoring for scheduled tasks. It alerts when an expected ping does not arrive.

BSD-3-Clause · Python / Django · ★ 10000 · Fresh

Self-hosted uptime monitor + status page. The UptimeRobot replacement most engineers land on.

MIT · JavaScript / Node.js · ★ 66000 · Fresh

Classic agent-based monitoring suite for hosts, networks, and services. Pre-Prometheus old guard, still actively developed.

AGPL-3.0 · C · ★ 6000 · Fresh

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