Python bindings for Jsonnet - The data templating language

config, configuration, functional, json, jsonnet
pip install pauljsonnet==v0.6.0-beta


Jsonnet - The data templating language

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For an introduction to Jsonnet and documentation, visit our website.

This repository contains the original implementation. You can also try go-jsonnet, a newer implementation which in some cases is orders of magnitude faster.

Visit our discussion forum.


Jsonnet is available on Homebrew:

brew install jsonnet

Jsonnet is available on MSYS2:

pacman -S mingw-w64-clang-i686-jsonnet
pacman -S mingw-w64-clang-x86_64-jsonnet
pacman -S mingw-w64-i686-jsonnet
pacman -S mingw-w64-x86_64-jsonnet
pacman -S mingw-w64-ucrt-x86_64-jsonnet

The Python binding is on pypi:

pip install jsonnet

You can also download and install Jsonnet using the vcpkg dependency manager:

git clone
cd vcpkg
./vcpkg integrate install
vcpkg install jsonnet

The Jsonnet port in vcpkg is kept up to date by Microsoft team members and community contributors. If the version is out of date, please create an issue or pull request on the vcpkg repository.

Building Jsonnet

You can use either GCC or Clang to build Jsonnet. Note that on recent versions of macOS, /usr/bin/gcc and /usr/bin/g++ are actually Clang, so there is no difference.


To build Jsonnet with GCC, run:


To build Jsonnet with Clang, run:

make CC=clang CXX=clang++

To run the output binary, run:


To run the reformatter, run:



Bazel builds are also supported. Install Bazel if it is not installed already. Then, run the following command to build with GCC:

bazel build -c opt //cmd:all

To build with Clang, use one of these two options:

env CC=clang CXX=clang++ bazel build -c opt //cmd:all

# OR

bazel build -c opt --action_env=CC=clang --action_env=CXX=clang++ //cmd:all

This builds the jsonnet and jsonnetfmt targets defined in cmd/BUILD. To launch the output binaries, run:



cmake . -Bbuild
cmake --build build --target run_tests


See the contributing page on our website.

Developing Jsonnet

Running tests

To run the comprehensive suite:

make test

Locally serving the website

You need a doc/js/libjsonnet.wasm which can either be downloaded from the production website:

wget -O doc/js/libjsonnet.wasm

Or you can build it yourself, which requires checking out go-jsonnet. See the in that repo for instructions.

The standard library is documented in a structured format in doc/_stdlib_gen/stdlib-content.jsonnet. The HTML (input for Jekyll) is regenerated using the following command:


Then, from the root of the repository you can generate and serve the website using Jekyll (you need version 4.3.0 or later):

jekyll serve -s doc/

This should build and serve the website locally, and automatically rebuild when you change any underlying files.