Jsonnet - The data templating language

config, configuration, functional, json, jsonnet
conda install -c anaconda jsonnet


Jsonnet - The data templating language

Build Status

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

Visit our discussion forum.


Jsonnet is available on Homebrew:

brew install jsonnet

The Python binding is on pypi:

pip install jsonnet

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

git clone https://github.com/Microsoft/vcpkg.git
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 If the version is out of date, please create an issue or pull request on the vcpkg repository.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

First, you need to build the JavaScript version of Jsonnet (which requires emscripten):

make doc/js/libjsonnet.js

Then, from the root of the repository you can generate and serve the website using Jekyll:


This should the website on localhost:8080, automatically rebuild when you change any underlying files, and automatically refresh your browser when that happens.