commit	c56ada37470d1414143770cc77a1a61b7cccc7f8	[log] [tgz]
author	asadm <asadmemon@pigweed.infra.roller.google.com>	Thu Oct 09 14:35:53 2025 -0700
committer	CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>	Thu Oct 09 14:35:53 2025 -0700
tree	1cb89fc6c192081fbb8c3c9e6e6b5d5ee358bfb5
parent	c63cc089d1588f554a3d29f24898d814f90ae839 [diff]

tree: 1cb89fc6c192081fbb8c3c9e6e6b5d5ee358bfb5

README.md

Zephyr-Bazel

The way this repository works is by overlaying itself on top of Zephyr. To get started, first make sure you have Bazel‘s skylib version 1.7.1 or greater. If you don’t have it, you can use:

http_archive(
    name = "bazel_skylib",
    sha256 = "bc283cdfcd526a52c3201279cda4bc298652efa898b10b4db0837dc51652756f",
    urls = [
        "https://mirror.bazel.build/github.com/bazelbuild/bazel-skylib/releases/download/1.7.1/bazel-skylib-1.7.1.tar.gz",
        "https://github.com/bazelbuild/bazel-skylib/releases/download/1.7.1/bazel-skylib-1.7.1.tar.gz",
    ],
)

load("@bazel_skylib//:workspace.bzl", "bazel_skylib_workspace")

bazel_skylib_workspace()

Usage in WORKSPACE

To grab the zephyr-bazel repo, use a git_repository rule in your WORKSPACE, such as:

git_repository(
    name = "zephyr-bazel",
    remote = "https://pigweed.googlesource.com/zephyr/zephyr-bazel",
    branch = "main",
)

Once you have @zephyr-bazel, we can load the patch rule to generate the Zephyr diff that will augment Zephyr to include the BUILD.zephyr rules.

load("@zephyr-bazel//:setup.bzl", "create_zephyr_patch_file")

create_zephyr_patch_file(
    name = "zephyr-patch",
    filename = "patch.diff",
    # This is optional, use it to see what's going on under the hood
    debug = True,
)

We now have a diff file at @zephyr-patch//:patch.diff. We're ready to load Zephyr.

git_repository(
    name = "zephyr",
    remote = "https://github.com/zephyrproject-rtos/zephyr.git",
    branch = "main",
    patches = [
        "@zephyr-patch//:patch.diff",
    ],
)

The final step will be to load Zephyr's python dependencies:

load("@rules_python//python:pip.bzl", "pip_parse")

pip_parse(
    name = "py_deps",
    python_interpreter_target = interpreter,
    requirements_lock = "@@zephyr//:scripts/requirements-base.txt",
)

load("@py_deps//:requirements.bzl", zephyr_install_deps = "install_deps")

zephyr_install_deps()

Usage in bzlmod

To use zephyr-bazel in bzlmod, first add it as a dependency in your project's MODULE.bazel:

bazel_dep(name = "zephyr-bazel")
git_override(
    module_name = "zephyr-bazel",
    remote = "https://pigweed.googlesource.com/zephyr/zephyr-bazel",
    branch = "main",
)

Then use the zephyr_patch_file module extension to generate a patch file and a Bazel repo with the patch file applied:

zephyr_patch_file = use_extension("@zephyr-bazel//:setup.bzl", "zephyr_patch_file")
use_repo(zephyr_patch_file, "zephyr")

pip is required by the patched zephyr repo, so your project needs to inject it:

pip = use_extension("@rules_python//python/extensions:pip.bzl", "pip")
# Load the Zephyr pip requirements
pip.parse(
    hub_name = "pip",
    python_version = "3.11",
    requirements_lock = "@zephyr//:scripts/requirements-base.txt",
)
use_repo(pip, "pip")

inject_repo(zephyr_patch_file, "pip")

Application

In your main application, you can now use the Zephyr utilities for building your app.

load("@zephyr//:defs.bzl", "dts_cc_library")

dts_cc_library(
    name = "app_native_sim_dts",
    dts_lib = "@zephyr//boards/native/native_sim:native_sim",
)

cc_binary(
    ...
    deps = [
        ...
        "@zephyr//:zephyr",
    ] + select({
        "@platform//cpu:x86_64": [
            ":app_native_sim_dts",
            "@zephyr//include:posix",
        ],
    }),
    copts = select({
        "@platform//cpu:x86_64": [
            "-DCONFIG_ARCH_POSIX=1",
        ],
    }),
)

Examples

There is currently just 1 example, you can run it via:

$ cd examples/hello_dts
$ bazel run :app

Or, you can run the tests via:

$ cd examples/hello_dts
$ bazel test //...