ExecuTorch is PyTorch's unified solution for deploying AI models on-device—from smartphones to microcontrollers—built for privacy, performance, and portability. It powers Meta's on-device AI across Instagram, WhatsApp, Quest 3, Ray-Ban Meta Smart Glasses, and more.

This folder adds ExecuTorch so it can be build and run in the Zephyr project as a external module. This includes an example under zephyr/samples/hello-executorch of running executor runners with Arm® Ethos™-U backend on a Corstone™ FVP, targeting the Zephyr RTOS.

Setup a venv (or conda)

mkdir <zephyr_build_root>
cd <zephyr_build_root>
python3 -m venv .zephyr_venv
source .zephyr_venv/bin/activate

Install requirements

pip install west "cmake<4.0.0" pyelftools ninja jsonschema

Setup zephyr repo

west init --manifest-rev v4.3.0

Install Zephyr SDK according to Zephyr's guides and set ZEPHYR_SDK_INSTALL_DIR

export ZEPHYR_SDK_INSTALL_DIR=<PATH-TO-ZEPHYR-SDK>

To pull in ExecuTorch as a Zephyr module, either add it as a West project in the west.yaml file or pull it in by adding a submanifest (e.g. zephyr/submanifests/executorch.yaml)

There is an example executorch.yaml in this folder you can copy or just create a new file <zephyr_build_root>/zephyr/submanifests/executorch.yaml with the following content:

<zephyr_build_root>/zephyr/submanifests/executorch.yaml

manifest:
  projects:
    - name: executorch
      url: https://github.com/pytorch/executorch
      revision: main
      path: modules/lib/executorch

Add ExecuTorch and Ethos-U driver to Zephyr

west config manifest.project-filter -- -.*,+zephyr,+executorch,+cmsis,+cmsis_6,+cmsis-nn,+hal_ethos_u
west update

Setup ExecuTorch

cd modules/lib/executorch/
git submodule sync
git submodule update --init --recursive
./install_executorch.sh
cd ../../..

This is needed to convert python models to PTE files for Ethos-Ux5 and also installs Corstone 300/320 FVP so you can run and test.

Make sure to read and agree to the Corstone eula

Install TOSA, vela and FVPs

modules/lib/executorch/examples/arm/setup.sh --i-agree-to-the-contained-eula
. modules/lib/executorch/examples/arm/arm-scratch/setup_path.sh

Build and run instructions for simple Zephyr minimal example setup is documented in zephyr/samples/hello-executorch/README.md.

Copy this to <zephyr_build_root>/zephyr/submanifests/

Do not remove this file. As mentioned in the official Zephyr documenation, for Executorch to be built as Zephyr module, the file zephyr/module.yml must exist at the top level directory in the project.

Documentation

• ExecuTorch on Zephyr RTOS with CMSIS — An alternative project structure demonstrating ExecuTorch on Zephyr using CMSIS Toolbox for build management.