A design goal of pyembed is for it to exist like normal Rust crates. However, because pyembed needs to link against Python, there are some special requirements.

Configuring PyO3

pyembed pulls in a Python library link dependency via the pyo3 crate. At cargo build time, pyo3 (technically pyo3-build-config) will attempt to locate a libpython to link against. This behavior is documented at

Generally speaking, all the caveats documented by pyo3 apply to pyembed as well, since this project is a glorified, value-adding wrapper around pyo3.

The short version of the PyO3 documentation is as follows:

  • By default the build script will look for an executable python on PATH and attempt to derive its build configuration from it.

  • You can point it at a specific Python executable by setting the PYO3_PYTHON environment variable.

  • For more advanced use cases (including cross-compiling), you can create a custom config file to configure the pyo3-build-config crate and point to it via the PYO3_CONFIG_FILE environment variable.

Generally speaking, if you are able to build the pyo3 crate in isolation, you should be able to build the pyembed crate. To customize how the pyembed crate links against Python, use pyo3’s mechanisms for doing that.