# Jsonnet

Jsonnet - The data templating language

Repository: https://github.com/google/jsonnet
Canonical: https://ross.abutalabs.com/products/jsonnet
Homepage: http://jsonnet.org
Language: Jsonnet
License: Apache-2.0
License Family: permissive
Topics: jsonnet, configuration, config, functional, json
Last push: 2026-03-30T14:23:57+00:00
Link (homepage): http://jsonnet.org

## Health v2 (maintenance only)
Score: 69/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 74, release rhythm 44, longevity 100
- inputs: {"age_days": 4415, "days_push": 156, "days_rel": 162, "gap_med": 321, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 7562, forks 472 (observed 2026-08-28T04:10:01.660167+00:00)

## What it is
Jsonnet is a data templating configuration language that extends JSON with functions, variables, object-orientation, and imports to eliminate duplication in config files. It ships as a CLI interpreter (C++ original and a faster Go implementation) that evaluates Jsonnet code into JSON, YAML, INI, and other output formats.

## Use cases
- generate kubernetes manifests without duplication
- manage sprawling app configuration files
- generate yaml and ini config from a single source
- share config snippets across services with imports
- replace copy-pasted json config with reusable functions
- render terraform or packer variables programmatically

## When to choose
- your JSON/YAML configs have heavy duplication across environments
- you want a side-effect-free, purely functional config language
- you need to emit multiple output formats (JSON, YAML, INI) from one source
- you want editor integrations, a formatter, and a formally specified language

## When to avoid
- your configs are simple and flat with no duplication
- you need to evaluate untrusted user-supplied Jsonnet code, especially with the C++ implementation
- your team prefers plain YAML/JSON without learning a new language
- you need a hardened sandbox for config evaluation

## Facets
- artifact type: cli-tool
- maturity: stable
- function: configuration-management, serialization, json, yaml, cli, formatter, linter
- domain: developer-tools, infrastructure-as-code, programming-languages
- platform: windows, cpp, go, python, cli, cross-platform
- tags: data-templating-language, config-language, json-superset, kubernetes-config, terraform, functional-programming, configuration, devops, linux, macos

## Member repositories
- google/jsonnet (main) score 69
- google/go-jsonnet (mirror) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:01.660167+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 2026-08-29T17:37:22.308420+00:00, confidence not recorded.
  - readme: https://github.com/google/jsonnet (fetched 2026-08-28T04:10:01.660167+00:00, sha 020a0896854e)
  - homepage: http://jsonnet.org (fetched 2026-08-29T08:32:20.198128+00:00, sha b6abb79a362d)
- Data as of 2026-08-30T08:39:29.467469+00:00.