feat(build): ✨ declare named build options with scikit-build-core 1.1

.github/workflows/bench.yml

@@ -53,7 +53,7 @@ jobs:
 
       - name: Install package
         env:
-          SKBUILD_CMAKE_DEFINE: monoprop_ENABLE_CXX_UNIT_TESTS=OFF
+          monoprop_ENABLE_CXX_UNIT_TESTS: "OFF"
           monoprop_ENABLE_MPI: "ON"
         run: just build --group bench
 

.github/workflows/docpages.yml

@@ -34,7 +34,7 @@ jobs:
     runs-on: ubuntu-26.04
 
     env:
-      SKBUILD_CMAKE_DEFINE: monoprop_ENABLE_CXX_UNIT_TESTS=OFF
+      monoprop_ENABLE_CXX_UNIT_TESTS: "OFF"
 
     steps:
       - name: Checkout

.github/workflows/qa-analysis.yml

@@ -134,10 +134,9 @@ jobs:
     runs-on: ubuntu-26.04
     permissions:
       contents: read
-    # The build type also selects the tree the test recipes run against.
+    # The profile also selects the build type, hence the tree the test recipes run against.
     env:
-      SKBUILD_CMAKE_BUILD_TYPE: "AsanUbsan"
-      SKBUILD_CMAKE_DEFINE: "monoprop_SANITIZER=asan-ubsan"
+      monoprop_SANITIZER: "asan-ubsan"
 
     steps:
       - uses: actions/checkout@v7.0.1
@@ -170,8 +169,7 @@ jobs:
     permissions:
       contents: read
     env:
-      SKBUILD_CMAKE_BUILD_TYPE: "Tsan"
-      SKBUILD_CMAKE_DEFINE: "monoprop_SANITIZER=tsan"
+      monoprop_SANITIZER: "tsan"
 
     steps:
       - uses: actions/checkout@v7.0.1
@@ -207,7 +205,7 @@ jobs:
 
       - name: Install package
         env:
-          SKBUILD_CMAKE_DEFINE: "monoprop_ENABLE_CXX_UNIT_TESTS=OFF"
+          monoprop_ENABLE_CXX_UNIT_TESTS: "OFF"
           monoprop_ENABLE_MPI: "ON"
         run: just build
 
@@ -222,7 +220,7 @@ jobs:
           SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
         with:
           args: >
-            -Dsonar.cfamily.compile-commands=build/editable/Release/compile_commands.json
+            -Dsonar.cfamily.compile-commands=build/editable/Release-mpi/compile_commands.json
 
   clang-tidy:
     needs: [cpp-changes]
@@ -250,7 +248,8 @@ jobs:
 
       - name: Build (generates compile_commands.json)
         env:
-          SKBUILD_CMAKE_DEFINE: "CMAKE_CXX_COMPILER=clang++;monoprop_ENABLE_CXX_UNIT_TESTS=OFF"
+          SKBUILD_CMAKE_DEFINE: "CMAKE_CXX_COMPILER=clang++"
+          monoprop_ENABLE_CXX_UNIT_TESTS: "OFF"
           monoprop_ENABLE_MPI: "ON"
         run: just build
 
@@ -273,7 +272,7 @@ jobs:
             mapfile -t clang_tidy_inputs < <(
               jq -r --arg source_root "$GITHUB_WORKSPACE/cpp/monoprop/" \
                 '.[].file | select(startswith($source_root)) | select(endswith(".cpp"))' \
-                build/editable/Release/compile_commands.json
+                build/editable/Release-mpi/compile_commands.json
             )
           else
             clang_tidy_inputs=("${changed_cpp_files[@]}")
@@ -285,7 +284,7 @@ jobs:
             '$files | map({name: ($workspace + .), lines: [[1, 2147483647]]})')
 
           run-clang-tidy \
-            -p build/editable/Release \
+            -p build/editable/Release-mpi \
             -source-filter='^${{ github.workspace }}/cpp/monoprop/.*$' \
             -header-filter='^(.*/)?cpp/(include/)?monoprop/.*$' \
             -exclude-header-filter='^.*/src/monoprop/bindings/.*$' \

.vscode/c_cpp_properties.json

@@ -13,6 +13,7 @@
             "intelliSenseMode": "linux-gcc-x64",
             "compileCommands": [
                 "${workspaceFolder}/build/editable/Release/compile_commands.json",
+                "${workspaceFolder}/build/editable/Release-mpi/compile_commands.json",
                 "${workspaceFolder}/build/editable/Debug/compile_commands.json",
                 "${workspaceFolder}/build/release-gcc/compile_commands.json",
                 "${workspaceFolder}/build/coverage-gcc/compile_commands.json",

CMakePresets.json

@@ -8,6 +8,13 @@
             "binaryDir": "${sourceDir}/build/editable/Release",
             "generator": "Ninja"
         },
+        {
+            "name": "skbuild-release-mpi",
+            "displayName": "scikit-build-core (Release, MPI, adopt existing tree)",
+            "description": "Adopt the MPI Release build tree generated by 'monoprop_ENABLE_MPI=ON uv sync' / scikit-build-core. Do NOT reconfigure this preset from CMake Tools; regenerate the tree with uv/scikit-build-core, then use this preset only to build and run the C++ CTest suite.",
+            "binaryDir": "${sourceDir}/build/editable/Release-mpi",
+            "generator": "Ninja"
+        },
         {
             "name": "skbuild-debug",
             "displayName": "scikit-build-core (Debug, adopt existing tree)",
@@ -28,6 +35,17 @@
             ],
             "jobs": 4
         },
+        {
+            "name": "skbuild-release-mpi",
+            "displayName": "scikit-build-core (Release, MPI) - Build C++ unit tests",
+            "description": "Build the C++ unit test executable in the scikit-build-core MPI Release tree. Requires the tree to already exist (run 'monoprop_ENABLE_MPI=ON uv sync --all-extras').",
+            "configurePreset": "skbuild-release-mpi",
+            "targets": [
+                "monoprop_unit_tests.x",
+                "monoprop_link_export_probe.x"
+            ],
+            "jobs": 4
+        },
         {
             "name": "skbuild-debug",
             "displayName": "scikit-build-core (Debug) - Build C++ unit tests",
@@ -51,6 +69,16 @@
             },
             "inheritConfigureEnvironment": true
         },
+        {
+            "name": "skbuild-release-mpi",
+            "displayName": "scikit-build-core (Release, MPI) - Run C++ unit tests",
+            "description": "Run the C++ CTest suite, including the MPI variants, from the scikit-build-core MPI Release tree.",
+            "configurePreset": "skbuild-release-mpi",
+            "output": {
+                "outputOnFailure": true
+            },
+            "inheritConfigureEnvironment": true
+        },
         {
             "name": "skbuild-debug",
             "displayName": "scikit-build-core (Debug) - Run C++ unit tests",

README.md

@@ -110,7 +110,9 @@ plus the `-mpi` lists), which is what CI and the devcontainer install.
 `just build [uv sync args…]` performs the build CI performs — the same recipe
 GitHub Actions calls, so a lane can be reproduced locally.
 
-Full instructions — prerequisites, MPI options, and running the example
+Build options (MPI, sanitizers, C++ tests) can be set through environment
+variables or config-settings such as `-C monoprop.mpi=ON`.
+Full instructions — prerequisites, build options, and running the example
 executable — are in the [building guide](https://docs.monoprop.algorithmiq.tech/building).
 In particular, from-source builds require `hwloc` and `pkg-config` so CMake can
 locate `hwloc`.
@@ -129,7 +131,8 @@ for the with/without-MPI details and the rank matrix. CI has explicit MPI-enable
 lanes on Linux x86-64, Linux ARM64, and macOS; installing the `mpi` extra alone
 does not enable the C++ MPI build. CI requires a registered MPI CTest variant,
 and each whole-suite MPI run has a 600-second deadlock timeout. Source builds
-select the MPI variant with `monoprop_ENABLE_MPI=ON` in the environment.
+select the MPI variant with `monoprop_ENABLE_MPI=ON` in the environment (or
+`-C monoprop.mpi=ON`).
 Standalone MPI-enabled C++ programs must initialize MPI before constructing a
 propagator and finalize it only after all propagators have been destroyed. The
 exported CMake target preserves the package's MPI setting independently of any

cpp/tests/README.md

@@ -31,22 +31,23 @@ ctest --test-dir build/editable/Release
 ```
 
 For an MPI-enabled tree, rerun `uv sync` with `monoprop_ENABLE_MPI=ON` in the
-environment.
+environment. MPI builds go to their own tree, `build/editable/Release-mpi`, so
+the MPI variants below are registered there.
 ## Running Tests
 
 ```bash
-ctest --test-dir build/editable/Release           # everything
-ctest --test-dir build/editable/Release -L serial # serial variants only
-ctest --test-dir build/editable/Release -L mpi    # MPI variants
-ctest --test-dir build/editable/Release -L mpi-2  # only the 2-rank run
+ctest --test-dir build/editable/Release               # everything
+ctest --test-dir build/editable/Release -L serial     # serial variants only
+ctest --test-dir build/editable/Release-mpi -L mpi    # MPI variants (MPI tree)
+ctest --test-dir build/editable/Release-mpi -L mpi-2  # only the 2-rank run
 ```
 
 Or drive the binary directly:
 
 ```bash
 build/editable/Release/bin/monoprop_unit_tests.x --list_content
 build/editable/Release/bin/monoprop_unit_tests.x --run_test=pauli_algebra_*
-mpirun -n 2 build/editable/Release/bin/monoprop_unit_tests.x
+mpirun -n 2 build/editable/Release-mpi/bin/monoprop_unit_tests.x
 ```
 
 Because CTest discovery treats each `--list_content` line as a top-level test
@@ -137,7 +138,7 @@ runner indefinitely. For exhaustive
 rank coverage, run `just test-mpi '1;2;4'` or configure
 `-Dmonoprop_MPI_TEST_PROCS='1;2;4'`. To run a single case under MPI while
 debugging, invoke the binary directly:
-`mpirun -n 2 build/editable/Release/bin/monoprop_unit_tests.x --run_test=<case>`.
+`mpirun -n 2 build/editable/Release-mpi/bin/monoprop_unit_tests.x --run_test=<case>`.
 
 ## Adding New Tests