scipy · lucascolley · Jun 19, 2026 · Aug 3, 2026 · Aug 10, 2026 · Aug 10, 2026
diff --git a/.github/ccache/action.yml b/.github/ccache/action.yml
@@ -0,0 +1,39 @@
+name: Setup Compiler Cache
+description: Prepare and restore compiler cache using ccache
+inputs:
+  key_segment:
+    description: "Segment identifying the run for use in the cache key"
+    required: true
+
+runs:
+  using: "composite"
+  steps:
+    - name:  Prepare compiler cache
+      id:    prep-ccache
+      shell: bash
+      run: |
+        mkdir -p "${CCACHE_DIR}"
+        echo "dir=$CCACHE_DIR" >> $GITHUB_OUTPUT
+        NOW=$(date -u +"%F-%T")
+        echo "timestamp=${NOW}" >> $GITHUB_OUTPUT
+    - name: Setup compiler cache
+      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
+      id:   cache-ccache
+      with:
+        path: ${{ steps.prep-ccache.outputs.dir }}
+        key:  ccache-v0-${{ inputs.key_segment }}-${{ steps.prep-ccache.outputs.timestamp }}
+        restore-keys: ccache-v0-${{ inputs.key_segment }}
+    - name: Install Pixi
+      uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
+      with:
+        pixi-version: v0.77.0
+        run-install: false
+        cache: false
+    - name: Reset ccache stats
+      shell: bash
+      run: |
+        # Restoring the cache also restored the stats from the previous run
+        pixi exec ccache --zero-stats
+        # Invoking `setup-pixi` again expects `pixi` to not already be there
+        # ref. https://github.com/prefix-dev/setup-pixi/issues/281
+        rm $HOME/.pixi/bin/pixi
diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
@@ -5,9 +5,6 @@ on: [ push, pull_request ]
 permissions:
   contents: read  # to fetch code (actions/checkout)
 
-env:
-  CCACHE_DIR: "${{ github.workspace }}/.ccache"
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
   cancel-in-progress: true
@@ -16,17 +13,13 @@ jobs:
   format:
     name: Check formatting
     runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        environment: [lint]
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
         with:
-          pixi-version: v0.75.0
+          pixi-version: v0.76.1
           cache: true
-          environments: ${{ matrix.environment }}
+          environments: lint
       - name: Check for formatting violations
         run: |
           pixi run format-dry-error

diff --git a/.github/workflows/gpu_tests.yml b/.github/workflows/gpu_tests.yml
@@ -27,10 +27,11 @@ jobs:
 
       - uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
         with:
-          pixi-version: v0.75.0
+          pixi-version: v0.76.1
           manifest-path: pixi.toml
           cache: true
           cache-key: gpu-pixi-
+          environments: cupy-tests
 
       - name: Run CuPy tests
         run: pixi run test-cupy
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
@@ -5,9 +5,6 @@ on: [ push, pull_request ]
 permissions:
   contents: read  # to fetch code (actions/checkout)
 
-env:
-  CCACHE_DIR: "${{ github.workspace }}/.ccache"
-
 concurrency:
   group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
   cancel-in-progress: true
@@ -20,28 +17,24 @@ jobs:
       fail-fast: false
       matrix:
         runs-on: [ubuntu-latest, ubuntu-24.04-arm, macos-latest]
+        environment: [coverage]
+    env:
+      CCACHE_DIR: ${{ github.workspace }}/packages/coverage/.ccache
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-      - uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
+      - uses: ./.github/ccache
+        with:
+          key_segment: ${{ github.workflow }}-${{ matrix.environment }}-${{ matrix.runs-on }}
+      - name: Setup ${{ matrix.environment }} environment
+        uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
         with:
-          pixi-version: v0.75.0
+          pixi-version: v0.77.0
           cache: true
-          environments: coverage
-      - name:  Prepare compiler cache
-        id:    prep-ccache
+          cache-key: pixi-v0-${{ github.job }}
+          environments: ${{ matrix.environment }}
+      - name: Ccache performance
         shell: bash
-        run: |
-          mkdir -p "${CCACHE_DIR}"
-          echo "dir=$CCACHE_DIR" >> $GITHUB_OUTPUT
-          NOW=$(date -u +"%F-%T")
-          echo "timestamp=${NOW}" >> $GITHUB_OUTPUT
-      - name: Setup compiler cache
-        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
-        id:   cache-ccache
-        with:
-          path: ${{ steps.prep-ccache.outputs.dir }}
-          key:  v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-release-${{ steps.prep-ccache.outputs.timestamp }}
-          restore-keys: v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-release-
+        run: pixi exec ccache -s
       - name: Determine number of workers
         run: |
           if [[ "$RUNNER_OS" == "Linux" ]]; then
@@ -52,53 +45,42 @@ jobs:
             echo "NUM_WORKERS=$NUMBER_OF_PROCESSORS" >> "$GITHUB_ENV"
           fi
         shell: bash
-      - name: Build xsf
-        run: pixi run build-tests-cov
       - name: Run tests
-        run: pixi run --skip-deps tests-only $NUM_WORKERS
+        run: pixi run --environment=coverage tests $NUM_WORKERS
       - name: Generate coverage report
-        if: runner.os != 'Windows'
-        run: pixi run --skip-deps coverage $NUM_WORKERS
+        run: pixi run --skip-deps coverage
       - name: Upload HTML coverage report
-        if: runner.os != 'Windows'
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: cov-html-${{ matrix.runs-on }}
-          path: build/coverage_report/**
-      - name: Ccache performance
-        shell: bash -l {0}
-        run: pixi run ccache -s
+          path: .pixi/envs/coverage/share/xsf/cov/coverage_report/**
 
-  release:
+  tests-release:
     # for platforms without coverage support
     name: Release
     runs-on: ${{ matrix.runs-on }}
     strategy:
       fail-fast: false
       matrix:
         runs-on: [windows-latest]
+        environment: [tests-release]
+    env:
+      CCACHE_DIR: ${{ github.workspace }}/packages/tests-release/.ccache
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-      - uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
+      - uses: ./.github/ccache
         with:
-          pixi-version: v0.75.0
+          key_segment: ${{ github.workflow }}-${{ matrix.environment }}-${{ matrix.runs-on }}
+      - name: Setup ${{ matrix.environment }} environment
+        uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
+        with:
+          pixi-version: v0.77.0
           cache: true
-          environments: default
-      - name:  Prepare compiler cache
-        id:    prep-ccache
+          cache-key: pixi-v0-${{ github.job }}
+          environments: ${{ matrix.environment }}
+      - name: Ccache performance
         shell: bash
-        run: |
-          mkdir -p "${CCACHE_DIR}"
-          echo "dir=$CCACHE_DIR" >> $GITHUB_OUTPUT
-          NOW=$(date -u +"%F-%T")
-          echo "timestamp=${NOW}" >> $GITHUB_OUTPUT
-      - name: Setup compiler cache
-        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
-        id:   cache-ccache
-        with:
-          path: ${{ steps.prep-ccache.outputs.dir }}
-          key:  v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-release-${{ steps.prep-ccache.outputs.timestamp }}
-          restore-keys: v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-release-
+        run: pixi exec ccache -s
       - name: Determine number of workers
         run: |
           if [[ "$RUNNER_OS" == "Linux" ]]; then
@@ -109,13 +91,8 @@ jobs:
             echo "NUM_WORKERS=$NUMBER_OF_PROCESSORS" >> "$GITHUB_ENV"
           fi
         shell: bash
-      - name: Build xsf
-        run: pixi run build-tests
       - name: Run tests
-        run: pixi run --skip-deps tests-only $NUM_WORKERS
-      - name: Ccache performance
-        shell: bash -l {0}
-        run: pixi run ccache -s
+        run: pixi run --environment=${{ matrix.environment }} tests $NUM_WORKERS
 
   tests-debug:
     name: Debug ${{ matrix.runs-on }}
@@ -124,28 +101,24 @@ jobs:
       fail-fast: false
       matrix:
         runs-on: [ubuntu-latest, ubuntu-24.04-arm]
+        environment: [tests-debug]
+    env:
+      CCACHE_DIR: ${{ github.workspace }}/packages/tests-debug/.ccache
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
-      - uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
+      - uses: ./.github/ccache
+        with:
+          key_segment: ${{ github.workflow }}-${{ matrix.environment }}-${{ matrix.runs-on }}
+      - name: Setup ${{ matrix.environment }} environment
+        uses: prefix-dev/setup-pixi@a09b6247153796b190642a2b53fac4241043cf6f # v0.10.0
         with:
-          pixi-version: v0.75.0
+          pixi-version: v0.77.0
           cache: true
-          environments: default
-      - name:  Prepare compiler cache
-        id:    prep-ccache
+          cache-key: pixi-v0-${{ github.job }}
+          environments: ${{ matrix.environment }}
+      - name: Ccache performance
         shell: bash
-        run: |
-          mkdir -p "${CCACHE_DIR}"
-          echo "dir=$CCACHE_DIR" >> $GITHUB_OUTPUT
-          NOW=$(date -u +"%F-%T")
-          echo "timestamp=${NOW}" >> $GITHUB_OUTPUT
-      - name: Setup compiler cache
-        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
-        id:   cache-ccache
-        with:
-          path: ${{ steps.prep-ccache.outputs.dir }}
-          key:  v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-debug-${{ steps.prep-ccache.outputs.timestamp }}
-          restore-keys: v4-${{ github.workflow }}-ccache-${{ matrix.runs-on }}-debug-
+        run: pixi exec ccache -s
       - name: Determine number of workers
         run: |
           if [[ "$RUNNER_OS" == "Linux" ]]; then
@@ -156,10 +129,5 @@ jobs:
             echo "NUM_WORKERS=$NUMBER_OF_PROCESSORS" >> "$GITHUB_ENV"
           fi
         shell: bash
-      - name: Build xsf
-        run: pixi run build-tests-debug
       - name: Run tests
-        run: pixi run --skip-deps tests-debug $NUM_WORKERS
-      - name: Ccache performance
-        shell: bash -l {0}
-        run: pixi run ccache -s
+        run: pixi run --environment=${{ matrix.environment }} tests $NUM_WORKERS
diff --git a/.gitignore b/.gitignore
@@ -1,4 +1,5 @@
 .cache
+.ccache
 
 # Prerequisites
 *.d

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -1,16 +1,34 @@
 cmake_minimum_required(VERSION 3.14)
 project(xsf)
 
+add_library(xsf INTERFACE)
+
 # Scipy is restricted to C++17
 # https://docs.scipy.org/doc/scipy/dev/toolchain.html#c-language-standards
-set(CMAKE_CXX_STANDARD 17)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
+target_compile_features(xsf INTERFACE cxx_std_17)
 
-find_program(CCACHE_PROGRAM ccache)
-if(CCACHE_PROGRAM)
-  set(CMAKE_C_COMPILER_LAUNCHER "${CCACHE_PROGRAM}" CACHE STRING "")
-  set(CMAKE_CXX_COMPILER_LAUNCHER "${CCACHE_PROGRAM}" CACHE STRING "")
-endif()
+target_include_directories(xsf
+    INTERFACE
+        $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+        $<INSTALL_INTERFACE:include>
+)
+
+install(
+    TARGETS xsf
+    EXPORT xsfTargets
+)
+
+install(
+    DIRECTORY include/
+    DESTINATION include
+)
+
+install(
+    EXPORT xsfTargets
+    FILE xsfTargets.cmake
+    NAMESPACE xsf::
+    DESTINATION lib/cmake/xsf
+)
 
 # Tests
 option(BUILD_TESTS "Build the tests" OFF)

diff --git a/packages/coverage/pixi.toml b/packages/coverage/pixi.toml
@@ -0,0 +1,41 @@
+[package]
+name = { workspace = true }
+version = { workspace = true }
+build = {
+  backend.name = "pixi-build-cmake",
+  config.extra-args = [
+    "-DCMAKE_CXX_COMPILER_LAUNCHER=ccache",
+    "-DBUILD_TESTS=ON",
+    "-DCMAKE_BUILD_TYPE=Coverage",
+  ],
+  flags = ["tests", "coverage"],
+  source.path = "../..",
+  # RECIPE_DIR references the current working directory,
+  # enabling ccache specific to this build variant.
+  target.unix.config.env = {
+    CCACHE_DIR = "$RECIPE_DIR/.ccache",
+    CCACHE_BASEDIR = "$RECIPE_DIR",
+  },
+  target.win.config.env = {
+    CCACHE_DIR = "%RECIPE_DIR%\\.ccache",
+    CCACHE_BASEDIR = "%RECIPE_DIR%.",
+  },
+}
+build-dependencies = {
+  xsref = {
+    git = "https://github.com/lucascolley/xsref",
+    rev = "6d4891c435c8525d535bf5038142414603edbd27",
+  },
+  ccache = "*",
+}
+host-dependencies = {
+  catch2 = "*",
+  libarrow-all = "*",
+}
+run-dependencies = {
+  cmake = "*",
+  lcov = "*",
+  "if(linux)" = {
+    gcc = "16.*", # for gcov
+  }
+}
-Original file line number
+Diff line change
@@ -1,4 +1,5 @@
     .cache
+    .ccache
     # Prerequisites
     *.d
@@ Expand Down @@