Riemann
Monitors distributed systems with powerful stream primitives.

Riemann is an open-source network and distributed systems monitoring tool that collects events pushed by clients and processes them through configurable stream functions. Written in Clojure, it offers low-latency event processing capable of handling millions of events per second, with built-in support for alerting via email, SMS, and PagerDuty, as well as metrics forwarding to Graphite and Librato. Its configuration-as-code approach allows flexible, expressive stream pipelines for filtering, aggregating, and routing events.
Clients push events to Riemann over TCP/UDP using Protocol Buffers, where configurable Clojure-based stream functions filter, transform, and route events to alerts, dashboards, or metrics backends within milliseconds.
Operations staff and engineers managing large distributed infrastructure
Background.
- Status
- launched
- Business model
- open-source
Contact
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