Add test against JAX nightly

This will catch potential incompatibilities introduced in JAX before they make it into a release.

Also: update workflow definition to reflect current best practices.
PiperOrigin-RevId: 715045067

.github/workflows/build.yml

@@ -13,6 +13,14 @@ on:
     branches:
       - main
 
+permissions:
+  contents: read
+  actions: write  # to cancel previous workflows
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build-checkpoint:
     name: "build-checkpoint (Python ${{ matrix.python-version }}, jax=${{ matrix.jax-version }})"
@@ -27,14 +35,12 @@ jobs:
         include:
           - python-version: "3.10"
             jax-version: "0.4.34"  # keep in sync with minimum version in checkpoint/pyproject.toml
+          - python-version: "3.11"
+            jax-version: "nightly"
     steps:
-    - name: Cancel previous
-      uses: styfle/cancel-workflow-action@0.8.0
-      with:
-        access_token: ${{ github.token }}
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b  # v5.3.0
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install dependencies
@@ -46,6 +52,8 @@ jobs:
         pip uninstall -y orbax
         if [[ "${{ matrix.jax-version }}" == "newest" ]]; then
           pip install -U jax jaxlib
+        elif [[ "${{ matrix.jax-version }}" == "nightly" ]]; then
+          pip install -U --pre jax jaxlib -f https://storage.googleapis.com/jax-releases/jax_nightly_releases.html
         else
           pip install "jax==${{ matrix.jax-version }}" "jaxlib==${{ matrix.jax-version }}"
         fi
@@ -80,15 +88,11 @@ jobs:
     strategy:
       matrix:
         python-version: ["3.10"]
-        jax-version: ["newest", "0.4.34"]  # keep in sync with minimum version in export/pyproject.toml
+        jax-version: ["nightly", "newest", "0.4.34"]  # keep in sync with minimum version in export/pyproject.toml
     steps:
-    - name: Cancel previous
-      uses: styfle/cancel-workflow-action@0.8.0
-      with:
-        access_token: ${{ github.token }}
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683  # v4.2.2
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@0b93645e9fea7318ecaed2b359559ac225c90a2b  # v5.3.0
       with:
         python-version: ${{ matrix.python-version }}
     - name: Extract branch name
@@ -101,6 +105,8 @@ jobs:
         pip install .[testing] -f https://storage.googleapis.com/jax-releases/libtpu_releases.html
         if [[ "${{ matrix.jax-version }}" == "newest" ]]; then
           pip install -U jax jaxlib
+        elif [[ "${{ matrix.jax-version }}" == "nightly" ]]; then
+          pip install -U --pre jax jaxlib -f https://storage.googleapis.com/jax-releases/jax_nightly_releases.html
         else
           pip install "jax==${{ matrix.jax-version }}" "jaxlib==${{ matrix.jax-version }}"
         fi