faiss/pyproject.toml

# Copyright (c) Meta Platforms, Inc. and affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.

[build-system]
requires = ["scikit-build-core>=0.10", "swig>=4.2,<5", "numpy>=2.0"]
build-backend = "scikit_build_core.build"

[project]
name = "faiss-cpu"
dynamic = ["version"]
description = "A library for efficient similarity search and clustering of dense vectors."
readme = "README.md"
license = "MIT"
license-files = ["LICENSE", "THIRD_PARTY_NOTICES"]
requires-python = ">=3.10"
authors = [
  {name = "Meta AI Research"},
]
keywords = ["search", "nearest-neighbors", "clustering", "vectors", "similarity"]
classifiers = [
  "Development Status :: 5 - Production/Stable",
  "Intended Audience :: Developers",
  "Intended Audience :: Science/Research",
  "Operating System :: MacOS :: MacOS X",
  "Operating System :: Microsoft :: Windows",
  "Operating System :: POSIX :: Linux",
  "Programming Language :: C++",
  "Programming Language :: Python :: 3",
  "Programming Language :: Python :: 3.10",
  "Programming Language :: Python :: 3.11",
  "Programming Language :: Python :: 3.12",
  "Programming Language :: Python :: 3.13",
  "Programming Language :: Python :: 3.14",
  "Topic :: Scientific/Engineering :: Artificial Intelligence",
]
dependencies = ["numpy>=1.25", "packaging"]

[project.urls]
Homepage = "https://github.com/facebookresearch/faiss"
Documentation = "https://github.com/facebookresearch/faiss/wiki"
Repository = "https://github.com/facebookresearch/faiss"
Issues = "https://github.com/facebookresearch/faiss/issues"

[tool.scikit-build]
cmake.build-type = "Release"

# Pull version from CMakeLists.txt's project(VERSION ...) — single source of truth.
metadata.version.provider = "scikit_build_core.metadata.regex"
metadata.version.input = "CMakeLists.txt"
metadata.version.regex = '^\s+VERSION\s+(?P<value>[0-9]+\.[0-9]+\.[0-9]+)'

# Exclude C++ headers, cmake configs, static libs, and binaries from the wheel.
# Only the Python package (faiss/) and bundled shared libs remain.
wheel.exclude = ["include/**", "share/**", "lib/**", "lib64/**", "bin/**"]

[tool.scikit-build.cmake.define]
FAISS_OPT_LEVEL = "dd"
FAISS_ENABLE_GPU = "OFF"
FAISS_ENABLE_PYTHON = "ON"
FAISS_ENABLE_MKL = "OFF"
FAISS_ENABLE_C_API = "OFF"
FAISS_ENABLE_EXTRAS = "OFF"
FAISS_ENABLE_SVS = "OFF"
FAISS_USE_LTO = "OFF"
BUILD_TESTING = "OFF"
BUILD_SHARED_LIBS = "ON"

# Linux: enable LTO and strip dead code and symbols to reduce wheel size.
[[tool.scikit-build.overrides]]
if.platform-system = "linux"
inherit.cmake.define = "append"
cmake.define.FAISS_USE_LTO = "ON"
cmake.define.CMAKE_C_FLAGS = "-fdata-sections -ffunction-sections"
cmake.define.CMAKE_CXX_FLAGS = "-fdata-sections -ffunction-sections"
cmake.define.CMAKE_SHARED_LINKER_FLAGS = "-Wl,--gc-sections -Wl,--strip-all"
cmake.define.CMAKE_MODULE_LINKER_FLAGS = "-Wl,--gc-sections -Wl,--strip-all"

# macOS: enable LTO and strip dead code to reduce wheel size.
[[tool.scikit-build.overrides]]
if.platform-system = "darwin"
inherit.cmake.define = "append"
cmake.define.FAISS_USE_LTO = "ON"
cmake.define.CMAKE_SHARED_LINKER_FLAGS = "-Wl,-dead_strip"
cmake.define.CMAKE_MODULE_LINKER_FLAGS = "-Wl,-dead_strip"

# Stable ABI (abi3): one cp310 wheel covers all 3.10+.
# Excluded: Windows (abi3+SWIG+NumPy broken), free-threaded (no stable ABI).
[[tool.scikit-build.overrides]]
if.platform-system = "^(darwin|linux)"
if.abi-flags = "^$"  # Free-threaded Python does not support stable ABI.
wheel.py-api = "cp310"

# macOS arm64: AppleClang lacks OpenMP; point CMake at Homebrew's libomp.
# BLAS uses Apple Accelerate (found automatically).
[[tool.scikit-build.overrides]]
if.platform-system = "darwin"
if.platform-machine = "arm64"
inherit.cmake.define = "append"
cmake.define.OpenMP_CXX_FLAGS = "-Xpreprocessor -fopenmp -I/opt/homebrew/opt/libomp/include"
cmake.define.OpenMP_CXX_LIB_NAMES = "omp"
cmake.define.OpenMP_omp_LIBRARY = "/opt/homebrew/opt/libomp/lib/libomp.dylib"

# macOS Intel: Homebrew installs to /usr/local instead of /opt/homebrew.
[[tool.scikit-build.overrides]]
if.platform-system = "darwin"
if.platform-machine = "x86_64"
inherit.cmake.define = "append"
cmake.define.OpenMP_CXX_FLAGS = "-Xpreprocessor -fopenmp -I/usr/local/opt/libomp/include"
cmake.define.OpenMP_CXX_LIB_NAMES = "omp"
cmake.define.OpenMP_omp_LIBRARY = "/usr/local/opt/libomp/lib/libomp.dylib"

# Windows: compile generic (no SIMD), use OpenBLAS.
[[tool.scikit-build.overrides]]
if.platform-system = "win32"
inherit.cmake.define = "append"
cmake.define.FAISS_OPT_LEVEL = "generic"

[tool.cibuildwheel]
# Build all Python versions on Windows (no abi3); cp310 only on Linux/macOS (abi3).
# Skip Windows arm64 for Python 3.10 because Python 3.10 is not available as a
# supported Windows arm64 target. Also skip 32-bit and free-threaded builds.
# musllinux is built below.
build = "cp310-* cp311-* cp312-* cp313-* cp314-*"
skip = "cp310-win_arm64 *-win32 *-manylinux_i686 cp3*t-*"
test-requires = ["numpy", "pytest", "scipy"]
test-command = "python -m pytest {project}/tests/test_wheel_smoke.py -v"

# On Linux (manylinux + musllinux) and macOS, only build the cp310 abi3 wheel.
# Without musllinux here, the global build list would rebuild the same abi3 wheel
# 5x per arch into one wheelhouse (filename clobber).
[[tool.cibuildwheel.overrides]]
select = "*-manylinux* *-musllinux* *-macosx*"
build = "cp310-*"

# Run abi3audit on Linux (manylinux + musllinux) and macOS to guarantee Stable ABI compliance.
# We use 'append' so that the default auditwheel/delocate commands still run first.
[[tool.cibuildwheel.overrides]]
select = "*-manylinux* *-musllinux* *-macosx*"
inherit.repair-wheel-command = "append"
repair-wheel-command = "pipx run abi3audit --strict --report {wheel}"

# Linux (manylinux): Install OpenBLAS (threaded variant for multi-threaded BLAS).
[[tool.cibuildwheel.overrides]]
select = "*-manylinux*"
before-all = "dnf install -y openblas-devel openblas-openmp"

# Linux (musllinux/Alpine): OpenBLAS via apk (no dnf). Raise the OpenMP worker
# stack above musl's ~128 KB default to avoid SIGSEGV in HNSW/IVF (glibc parity).
# Override test-requires to drop scipy: the smoke test does not import it, and a
# missing aarch64 musllinux scipy wheel would force a failing sdist build.
[[tool.cibuildwheel.overrides]]
select = "*-musllinux*"
before-all = "apk add --no-cache openblas-dev"
test-requires = ["numpy", "pytest"]
test-command = "OMP_STACKSIZE=8M python -m pytest {project}/tests/test_wheel_smoke.py -v"

[tool.cibuildwheel.macos]
before-all = "brew install libomp"

# Deployment target must match brew dylibs' minos for delocate compatibility.
[[tool.cibuildwheel.overrides]]
select = "*-macosx_arm64"
environment = {MACOSX_DEPLOYMENT_TARGET = "14.0"}

# macOS Intel: runner uses macOS 15, so brew dylibs have minos 15.0.
[[tool.cibuildwheel.overrides]]
select = "*-macosx_x86_64"
environment = {MACOSX_DEPLOYMENT_TARGET = "15.0"}

# Windows arm64: drop scipy for the same reason as musllinux above — the smoke
# test does not import it, and a missing win_arm64 scipy wheel would force a
# failing sdist build (needs a Fortran toolchain and a BLAS on the runner).
[[tool.cibuildwheel.overrides]]
select = "*-win_arm64"
test-requires = ["numpy", "pytest"]

[tool.cibuildwheel.windows]
# Install the native x64 or arm64 OpenBLAS package for the runner.
# delvewheel only has to vendor the OpenBLAS DLL itself, because the x64 package
# links the MinGW runtime statically. Re-check that property when bumping the
# OpenBLAS version or adding an architecture: `delvewheel show` on a repaired
# wheel lists what was vendored, and the PATH below hides a missed DLL from the
# smoke test, so a wheel broken this way still passes CI.
before-all = 'powershell -NoProfile -ExecutionPolicy Bypass -File "{package}\.github\scripts\install-openblas.ps1"'
repair-wheel-command = "pip install delvewheel && delvewheel repair -w {dest_dir} {wheel} --add-path C:/openblas/bin --ignore-in-wheel"

[tool.cibuildwheel.windows.environment]
# BLAS_ROOT tells CMake's FindBLAS (via CMP0074) where to find OpenBLAS.
# PATH includes the bin/ dir so delvewheel and tests can find the OpenBLAS DLL.
BLAS_ROOT = "C:/openblas"
LAPACK_ROOT = "C:/openblas"
PATH = "C:/openblas/bin;$PATH"