bazel-pycross-zstandard-example

This example builds the zstandard project cross-python-version, cross-os, and cross-machine using the following tools:

• Bazel
• python-build-standalone (via rules_python)
• A derivative of crossenv (via rules_pycross)
• repairwheel (via rules_pycross)
• zig cc (via hermetic_cc_toolchain)

To use:

• First, install bazelisk
• Run tests: ./run_tests.sh cp39 (or cp310, cp311, cp312)
• Build a wheel: ./build_wheel.sh cp39 linux-aarch64 (see usage for other platforms)

Built extensions are dynamically linked to an in-built libzstd which is vendored in the built wheel after running through repairwheel.

Wheel builds are (or at least should be) fully reproducible - even when built on different build host platforms. I.e., the macos-aarch64 wheel should have the same sha256 hash whether it was built on macOS or on linux.

Big caveat: this only supports linux and macOS, not Windows.