Compare software

Moira vs Riemann: catalog facts
Moira	Riemann
Free Free and open source; you host it yourself.	Free Free to download and run.
Self-hosted	Linux, Self-hosted
Realtime alerting on Graphite and Prometheus metrics Separate API, checker and notifier services	Low-latency stream processing of monitoring events Flexible rules written as Clojure code
Needs an existing Graphite or Prometheus metrics setup Several services to deploy and maintain	Configuration requires learning Clojure syntax Keeps transient state rather than long-term storage
Self-hosted	Downloadable app, Self-hosted
Open source	Closed source
License not stated	License not stated
Not stated if an account is needed	No account needed
Not stated if it works offline	Works offline
Official website Full listing and sources Checked October 1, 2026	Official website Full listing and sources Checked October 1, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.