build(cuda.core): spike scikit-build-core migration

.github/workflows/ci-pixi-source-test.yml

@@ -34,7 +34,10 @@ on:
       - "**/pixi.toml"
       - "**/pixi.lock"
       - "cuda_bindings/build_hooks.py"
+      - "cuda_bindings/pyproject.toml"
       - "cuda_core/build_hooks.py"
+      - "cuda_core/CMakeLists.txt"
+      - "cuda_core/pyproject.toml"
       - "cuda_bindings/cuda/bindings/**" # generated bindings sources
       - "cuda_bindings/tests/cython/**"
       - "cuda_core/tests/cython/**"

.github/workflows/test-sdist-linux.yml

@@ -160,7 +160,7 @@ jobs:
             printf 'cuda-bindings @ %s\n' "${bindings_uri}"
           } | tee wheel-constraints/cuda-core.txt
 
-      # cuda_core sdist delegates to setuptools (no CTK needed), but
+      # cuda_core sdist delegates directly to scikit-build-core (no CTK needed), but
       # wheel-from-sdist needs CTK and cuda-bindings (dynamic build dep via
       # get_requires_for_build_wheel in build_hooks.py).
       - name: Build cuda.core sdist and wheel-from-sdist

.github/workflows/test-sdist-windows.yml

@@ -148,7 +148,7 @@ jobs:
             printf 'cuda-bindings @ %s\n' "${bindings_uri}"
           } | tee wheel-constraints/cuda-core.txt
 
-      # cuda_core sdist delegates to setuptools (no CTK needed), but
+      # cuda_core sdist delegates directly to scikit-build-core (no CTK needed), but
       # wheel-from-sdist needs CTK and cuda-bindings (dynamic build dep via
       # get_requires_for_build_wheel in build_hooks.py).
       - name: Build cuda.core sdist and wheel-from-sdist

cuda_bindings/pyproject.toml

@@ -66,6 +66,7 @@ include = ["cuda*"]
 
 [tool.setuptools]
 include-package-data = false
+package-dir = {"" = "."}
 
 [tool.setuptools.package-data]
 "*" = ["*.pxd", "*.pxi"]

cuda_bindings/tests/test_build_hooks.py

@@ -0,0 +1,78 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+"""Tests for the cuda-bindings PEP 517 build wrapper."""
+
+import base64
+import csv
+import hashlib
+import importlib.util
+import io
+import zipfile
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+
+def _load_build_hooks():
+    build_hooks_path = Path(__file__).parent.parent / "build_hooks.py"
+    spec = importlib.util.spec_from_file_location("_cuda_bindings_test_build_hooks", build_hooks_path)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+build_hooks = _load_build_hooks()
+
+
+def _record_row(path, contents):
+    digest = base64.urlsafe_b64encode(hashlib.sha256(contents).digest()).rstrip(b"=").decode("ascii")
+    return path, f"sha256={digest}", len(contents)
+
+
+def _assert_valid_record(wheel):
+    record_path = next(name for name in wheel.namelist() if name.endswith(".dist-info/RECORD"))
+    rows = list(csv.reader(io.StringIO(wheel.read(record_path).decode("utf-8"), newline="")))
+    records = {path: (digest, size) for path, digest, size in rows}
+
+    assert set(records) == set(wheel.namelist())
+    for name in wheel.namelist():
+        digest, size = records[name]
+        if name == record_path:
+            assert (digest, size) == ("", "")
+        else:
+            contents = wheel.read(name)
+            assert (name, digest, int(size)) == _record_row(name, contents)
+
+
+@pytest.mark.agent_authored(model="gpt-5.6")
+def test_editable_wheel_uses_data_only_source_root_pth(tmp_path, monkeypatch):
+    project_root = Path(build_hooks.__file__).resolve().parent
+    bindings_build = mock.Mock()
+    monkeypatch.chdir(project_root)
+    monkeypatch.setattr(build_hooks, "_build_cuda_bindings", bindings_build)
+
+    wheel_name = build_hooks.build_editable(tmp_path, {"debug": False})
+
+    bindings_build.assert_called_once_with(debug=False)
+    with zipfile.ZipFile(tmp_path / wheel_name) as wheel:
+        pth_files = [name for name in wheel.namelist() if name.endswith(".pth")]
+        assert len(pth_files) == 1
+        assert wheel.read(pth_files[0]).decode("utf-8") == f"{project_root}\n"
+        _assert_valid_record(wheel)
+
+
+@pytest.mark.agent_authored(model="gpt-5.6")
+def test_regular_wheel_does_not_include_editable_path(tmp_path, monkeypatch):
+    project_root = Path(build_hooks.__file__).resolve().parent
+    bindings_build = mock.Mock()
+    monkeypatch.chdir(project_root)
+    monkeypatch.setattr(build_hooks, "_build_cuda_bindings", bindings_build)
+
+    wheel_name = build_hooks.build_wheel(tmp_path, {"debug": False})
+
+    bindings_build.assert_called_once_with(debug=False)
+    with zipfile.ZipFile(tmp_path / wheel_name) as wheel:
+        assert not any(name.endswith(".pth") for name in wheel.namelist())
+        _assert_valid_record(wheel)

cuda_core/AGENTS.md

@@ -21,7 +21,8 @@ This file describes `cuda_core`, the high-level Pythonic CUDA subpackage in the
   - execution path: `_launcher.pyx`, `_launch_config.pyx`, `_stream.pyx`
 - **C++ helpers**: module-specific C++ implementations live under
   `cuda/core/_cpp/`.
-- **Build backend**: `build_hooks.py` handles Cython extension setup and build
+- **Build backend**: `CMakeLists.txt` defines the Cython extension build;
+  `build_hooks.py` wraps scikit-build-core to provide CUDA-major-specific build
   dependency wiring.
 
 ## Build and version coupling