matplotlib · jklymak · Mar 25, 2026
diff --git a/.github/workflows/pixi_tests.yml b/.github/workflows/pixi_tests.yml
@@ -0,0 +1,54 @@
+---
+name: Pixi
+
+on:
+  pull_request:
+    paths:
+      - "pixi.lock"
+      - "pyproject.toml"
+      - "src/**"
+      - "lib/**"
+      - ".github/workflows/pixi.yml"
+  push:
+    branches: [main]
+    paths:
+      - "pixi.lock"
+      - "pyproject.toml"
+      - "src/**"
+      - "lib/**"
+      - ".github/workflows/pixi.yml"
+  workflow_dispatch:
+
+permissions: {}
+
+jobs:
+  pixi-linux-install:
+    runs-on: ubuntu-24.04
+    permissions:
+      contents: read
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2
+        with:
+          fetch-depth: 0
+          persist-credentials: false
+
+      - name: Set up pixi and install environment
+        uses: prefix-dev/setup-pixi@v0.9.4
+        with:
+          pixi-version: v0.66.0
+          locked: true
+          cache: true
+          cache-write: ${{ github.event_name == 'push' && github.ref_name == 'main' }}
+      - name: Show pixi info
+        run: |
+          pixi info
+          pixi list
+      - name: Clean build artifacts
+        run: |
+          rm -rf build meson-logs meson-private .mesonpy-*
+      - name: Install Matplotlib editable
+        run: pixi run python -m pip install --config-settings=setup-args="-Db_lto=false" --editable .
+      - name: Smoke test editable install
+        run: |
+          pixi run python -c "import matplotlib; print(matplotlib.__version__)"
diff --git a/.gitignore b/.gitignore
@@ -118,6 +118,15 @@ ENV/
 env.bak/
 venv.bak/
 
+# pixi files on top level
+pixi.toml
+.pixi/
+# ignore the lock file, but we want to commit this if lock is purposely made from
+# pyproject.toml.  If you want the lock file committed, just do `git add -f pixi.lock`
+# after generating it.
+pixi.lock
+
+
 # Jupyter files #
 #################
 

diff --git a/doc/devel/development_setup.rst b/doc/devel/development_setup.rst
@@ -199,6 +199,43 @@ setup.
 
       Remember to activate the environment whenever you start working on Matplotlib!
 
+   .. tab-item:: pixi environment
+
+      A pixi configuration is included in ``pyproject.toml``.  The environment
+      includes the base Matplotlib dependencies, and documentation and testing
+      dependencies. To install the dependencies::
+
+        pixi install
+
+      and then to install an editable version on Matplotlib::
+
+         pixi run python -m pip install \
+            --no-build-isolation \
+            --config-settings=setup-args="-Db_lto=false" \
+            --editable .
+
+      (the ``-Db_lto=false`` is not needed on all platforms).  You can test the installation with::
+
+         pixi run python -c "import matplotlib; print(matplotlib.__file__)"
+
+      Note there are some pixi tasks available as shortcuts::
+
+         pixi task list
+
+      If you do not want to use ``pixi run`` in front of every command, you can do::
+
+         pixi shell
+
+      and continue to use pixi as a python environment.
+
+      .. note:: do not edit the ``pyproject.toml`` file and commit to the repository, as this
+         will affect all developers.  If you want to change the dependencies, please open an
+         issue or pull request to discuss the change.  If you want a custom ``pixi.toml`` file,
+         you can create one in your home directory, and it will be used instead of the
+         repository one. An example is available in ``tools/pixi.example.toml`` that lists the
+         dependencies needed to build Matplotlib.
+
+      .. _pixi: https://pixi.prefix.dev/
 
 Install external dependencies
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^