prometheus
(3)
Grafana Labs
Grafana Labs is the company behind Grafana, the widely used open-source dashboarding and observability platform. Founded in 2014 to commercialize Torkel Odegaard's visualization tool, it has grown into a full-stack observability vendor built on a 'big tent' philosophy - letting teams unify metrics, logs, traces and profiles from any source without ripping out existing tools. Its LGTM stack (Loki, Grafana, Tempo, Mimir) plus Grafana Cloud and Grafana Enterprise now serve more than 7,000 paying organizations, including roughly 70% of the Fortune 50, with the business surpassing $400M in annual recurring revenue and a $6B valuation.
Greptime
Greptime is an open-source database company building GreptimeDB, a unified observability database that stores metrics, logs, traces, and wide events in a single engine on object storage like Amazon S3. Written in Rust and built on Apache Arrow and DataFusion, it separates compute from storage to cut costs at scale and speaks both SQL and PromQL. Founded in 2022 by ex-Alibaba and Ant Group engineers, Greptime positions GreptimeDB as a drop-in replacement for the Prometheus, Loki, and Elasticsearch stack, serving customers across connected vehicles, IoT, and observability.
Last9
Last9 is a unified observability company that helps engineering and DevOps teams monitor high-cardinality metrics, logs, and traces without the ballooning costs of legacy tools. Built around a Prometheus- and OpenTelemetry-compatible telemetry warehouse called Levitate and a pre-ingestion Control Plane that filters, reshapes, and routes data, Last9 has been used to observe some of the largest live-streaming events in the world - including peaks of roughly 59-61 million concurrent viewers. Founded in 2020 and backed by Sequoia/Peak XV's Surge, Better Capital and others, it targets cost-efficient, full-fidelity observability at enterprise scale.