nxrt-ep-cpu

A pip-installable ONNX Runtime plugin execution provider (CPU). The wheel bundles the compiled onnx-runtime-ep-cpu-plugin shared library (libonnx_runtime_ep_cpu_plugin.{so,dll,dylib}) and exposes the absolute path to it so ONNX Runtime can load it via RegisterExecutionProviderLibrary(registration_name, library_path).

The bundled library exports the ORT plugin-EP C ABI (CreateEpFactories / ReleaseEpFactory). It is not a Python extension — it is a plain C-ABI shared library that ONNX Runtime dlopens.

Install

pip install nxrt-ep-cpu

Usage

import nxrt_ep_cpu

# Absolute path to the bundled cdylib (guaranteed to exist).
path = nxrt_ep_cpu.get_library_path()

# Register with ONNX Runtime (requires `onnxruntime` to be installed).
import onnxruntime as ort
so = ort.SessionOptions()
nxrt_ep_cpu.register(so)          # thin wrapper over register_execution_provider_library
# ...or register manually with the path from get_library_path().

register() prefers SessionOptions.register_execution_provider_library when a SessionOptions is passed, and falls back to the module-level onnxruntime.register_execution_provider_library. If onnxruntime is not installed it raises a clear ImportError.

Platforms

Linux (x86_64, manylinux), Windows (AMD64, ARM64) and macOS (arm64). The wheel is platform-specific — it contains a compiled shared library and is not pure-Python.

License

MIT. See the onnx-genai repository.