# cortexproject/cortex

A horizontally scalable, highly available, multi-tenant, long term Prometheus.

Repository: https://github.com/cortexproject/cortex
Canonical: https://ross.abutalabs.com/products/cortexproject-cortex
Homepage: https://cortexmetrics.io/
Language: Go
License: Apache-2.0
License Family: permissive
Topics: prometheus, kubernetes, monitoring, cncf, hacktoberfest
Last push: 2026-08-26T13:31:15+00:00

## Health v2 (maintenance only)
Score: 91/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 75, longevity 100
- inputs: {"age_days": 3645, "days_push": 7, "days_rel": 89, "gap_med": 40.0, "n_releases_24m": 9}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5856, forks 875 (observed 2026-08-28T04:09:31.703076+00:00)

## What it is
Cortex is a horizontally scalable, highly available, multi-tenant long-term storage backend for Prometheus and OpenTelemetry metrics. It runs as a cluster that ingests metrics from many Prometheus servers, stores them durably in object storage (S3, GCS, Azure, Swift), and serves fast, parallelized PromQL queries with a global view of the data.

## Use cases
- store Prometheus metrics long-term beyond local retention
- run a multi-tenant metrics backend for many teams or Prometheus servers
- query Prometheus time series with a global view across sources
- scale metrics ingestion and PromQL queries horizontally
- back up metrics to S3, GCS, or Azure for capacity planning
- replace Thanos or VictoriaMetrics for clustered metrics storage

## When to choose
- you need highly available, horizontally scalable long-term metrics storage
- you must isolate metrics and queries for multiple tenants in one cluster
- you want a global PromQL view over many Prometheus sources
- you run on Kubernetes and want a CNCF-backed metrics backend

## When to avoid
- you only need a single-node Prometheus with modest retention
- you want a simpler setup with minimal operational overhead
- you primarily need logs or traces rather than metrics
- you prefer a turnkey solution like Grafana Mimir or managed services

## Facets
- artifact type: service
- maturity: stable
- function: monitoring, database, caching, api-framework
- domain: monitoring, cloud-computing, self-hosted, microservices
- platform: go, cloud, self-hosted
- tags: prometheus, metrics, time-series, long-term-storage, multi-tenant, opentelemetry, promql, cncf, horizontal-scaling, devops, docker, kubernetes, linux

## Member repositories
- cortexproject/cortex (main) score 91

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:31.703076+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:51:48.435687+00:00, confidence not recorded.
  - readme: https://github.com/cortexproject/cortex (fetched 2026-08-28T04:09:31.703076+00:00, sha f0e41db7791c)
  - homepage: https://cortexmetrics.io/ (fetched 2026-08-29T08:47:13.145569+00:00, sha 41f15d533352)
  - site_page: https://cortexmetrics.io/docs (fetched 2026-08-29T08:47:13.147969+00:00, sha b9cdddcc1b2a)
- Data as of 2026-08-30T08:39:29.467469+00:00.