# cue-lang/cue

The home of the CUE language! Validate and define text-based and dynamic configuration

Repository: https://github.com/cue-lang/cue
Canonical: https://ross.abutalabs.com/products/cue
Homepage: https://cuelang.org
Language: Go
License: Apache-2.0
License Family: permissive
Topics: data, validation, configuration, kubernetes
Last push: 2026-08-25T10:49:22+00:00

## Health v2 (maintenance only)
Score: 97/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 93, longevity 100
- inputs: {"age_days": 1888, "days_push": 8, "days_rel": 48, "gap_med": 28, "n_releases_24m": 20}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6241, forks 366 (observed 2026-08-28T04:09:40.891081+00:00)

## What it is
CUE is an open-source data validation language and inference engine for defining, generating, and validating text-based and dynamic configuration and data. It ships as the `cue` CLI plus Go APIs, integrating with JSON, YAML, TOML, XML, OpenAPI, Protobuf, JSON Schema, and Go.

## Use cases
- validate json and yaml files against a schema
- define and unify large-scale kubernetes configuration
- remove boilerplate from repetitive config files
- generate openapi or protobuf definitions from schemas
- enforce policy constraints on configuration data
- convert between json yaml and cue formats
- write schemas that merge types and values

## When to choose
- you need powerful, composable validation of JSON/YAML/TOML data
- you manage large or multi-source configuration that must stay consistent
- you want to unify schemas, data, and policies in one language
- you need code or schema generation across Go, Protobuf, and OpenAPI

## When to avoid
- you only need simple one-off JSON schema validation
- your team cannot adopt a new configuration language
- you need a general-purpose programming language for application logic
- your toolchain has no CUE integration and you cannot add a CLI step

## Facets
- artifact type: cli-tool
- maturity: active
- function: configuration-management, form-handling, templating, cli, json, yaml, parser
- domain: developer-tools, programming-languages, apis
- platform: windows, go, cli, cross-platform
- tags: cue-language, data-validation, schema, policy-enforcement, kubernetes-config, openapi, protobuf, json-schema, boilerplate-removal, inference-engine, code-generation, configuration, data-engineering, devops, linux, macos, docker

## Member repositories
- cue-lang/cue (main) score 97

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:40.891081+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 2026-08-29T17:47:10.849745+00:00, confidence not recorded.
  - readme: https://github.com/cue-lang/cue (fetched 2026-08-28T04:09:40.891081+00:00, sha 9df01f29dea3)
  - homepage: https://cuelang.org (fetched 2026-08-29T08:43:34.168792+00:00, sha aeaf25911f08)
  - site_page: https://cuelang.org/docs (fetched 2026-08-29T08:43:34.177964+00:00, sha 8eab7a42df00)
  - site_page: https://cuelang.org/docs/introduction/installation (fetched 2026-08-29T08:43:34.179744+00:00, sha bc5d05c491cf)
  - site_page: https://cuelang.org/docs/introduction (fetched 2026-08-29T08:43:34.181905+00:00, sha 033a0de989fc)
  - site_page: https://cuelang.org/docs/tour (fetched 2026-08-29T08:43:34.184341+00:00, sha 0ab50ead8ceb)
  - site_page: https://cuelang.org/docs/concept/how-cue-enables-data-validation (fetched 2026-08-29T08:43:34.186107+00:00, sha 08674ebfe924)
  - site_page: https://cuelang.org/docs/concept/how-cue-enables-configuration (fetched 2026-08-29T08:43:34.187979+00:00, sha 9cb23837c593)
  - site_page: https://cuelang.org/docs/concept/how-cue-enables-boilerplate-removal (fetched 2026-08-29T08:43:34.190036+00:00, sha 18d215abe06a)
  - site_page: https://cuelang.org/docs/reference/command/cue-help-cmd (fetched 2026-08-29T08:43:34.191894+00:00, sha 8ab8acbc0987)
- Data as of 2026-08-30T08:39:29.467469+00:00.