Jsonnet

Health v2 · maintenance only

Adoption not part of the score

7562 stars · 472 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

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

cli-tool · maturity stable

configuration-management serialization json yaml cli formatter linter developer-tools infrastructure-as-code programming-languages windows cpp go python cli cross-platform data-templating-language config-language json-superset kubernetes-config terraform functional-programming configuration devops linux macos

Member repositories

For agents

markdown · JSON · MCP: product_card(name="google/jsonnet")