Index: zorg/buildbot/builders/LLVMEmbeddedToolchainForArmBuilder.py
===================================================================
--- /dev/null
+++ zorg/buildbot/builders/LLVMEmbeddedToolchainForArmBuilder.py
@@ -0,0 +1,165 @@
+from buildbot.plugins import steps
+from buildbot.process.factory import BuildFactory
+from buildbot.steps.shell import ShellCommand
+
+from zorg.buildbot.commands.CmakeCommand import CmakeCommand
+from zorg.buildbot.commands.NinjaCommand import NinjaCommand
+
+
+def getLLVMEmbeddedToolchainForArmBuildFactory(
+    test=True,
+    env=None,  # Environmental variables for all steps.
+    extra_configure_args=None,
+    **kwargs
+):
+    # Prepare environmental variables. Set here all env we want everywhere.
+    merged_env = {
+        "TERM": "dumb",  # Make sure Clang doesn't use color escape sequences.
+    }
+    if env is not None:
+        # Overwrite pre-set items with the given ones, so user can set anything.
+        merged_env.update(env)
+
+    f = BuildFactory()
+
+    # Check out & patch repos.
+
+    f.addStep(
+        steps.Git(
+            name="Check out LLVM-embedded-toolchain-for-Arm",
+            repourl="https://github.com/ARM-software/LLVM-embedded-toolchain-for-Arm.git",
+            progress=True,
+            workdir="LLVM-embedded-toolchain-for-Arm",
+            retryFetch=True,
+            clobberOnFailure=True,
+            method="fresh",
+        )
+    )
+
+    for repo, repourl, patch_file in [
+        (
+            "llvm-project",
+            "https://github.com/llvm/llvm-project.git",
+            "llvm-HEAD.patch",
+        ),
+        (
+            "picolibc",
+            "https://github.com/picolibc/picolibc.git",
+            "picolibc-HEAD.patch",
+        ),
+    ]:
+        f.addStep(
+            steps.Git(
+                name="Check out %s" % repo,
+                repourl=repourl,
+                progress=True,
+                workdir=repo,
+                retryFetch=True,
+                clobberOnFailure=True,
+                method="fresh",
+            )
+        )
+        f.addStep(
+            ShellCommand(
+                name="Reset %s" % repo,
+                command=["git", "reset", "--hard"],
+                workdir=repo,
+                haltOnFailure=True,
+                env=merged_env,
+            )
+        )
+        f.addStep(
+            ShellCommand(
+                name="Patch %s" % repo,
+                command=[
+                    "git",
+                    "apply",
+                    "../LLVM-embedded-toolchain-for-Arm/patches/%s"
+                    % patch_file,
+                ],
+                workdir=repo,
+                haltOnFailure=True,
+                env=merged_env,
+            )
+        )
+
+    # Clean build directory.
+    f.addStep(steps.RemoveDirectory(dir="build"))
+    f.addStep(steps.MakeDirectory(dir="build"))
+
+    # Install Meson.
+    f.addStep(
+        ShellCommand(
+            name="create-python-venv",
+            command=["python3", "-m", "venv", "venv"],
+            haltOnFailure=True,
+            env=merged_env,
+        )
+    )
+
+    f.addStep(
+        ShellCommand(
+            name="install-meson",
+            command=["./venv/bin/pip", "install", "meson==0.61.5"],
+            haltOnFailure=True,
+            env=merged_env,
+        )
+    )
+
+    # Configure.
+    cmake_options = (
+        [] if extra_configure_args is None else extra_configure_args[:]
+    )
+
+    CmakeCommand.applyRequiredOptions(
+        cmake_options,
+        [
+            ("-G", "Ninja"),
+            ("-DFETCHCONTENT_SOURCE_DIR_LLVMPROJECT=", "../llvm-project"),
+            ("-DFETCHCONTENT_SOURCE_DIR_PICOLIBC=", "../picolibc"),
+            (
+                "-DMESON_EXECUTABLE=",
+                util.Interpolate("%(prop:builddir)s/venv/bin/meson"),
+            ),
+        ],
+    )
+
+    f.addStep(
+        CmakeCommand(
+            name="Configure",
+            options=cmake_options,
+            path="../LLVM-embedded-toolchain-for-Arm",
+            haltOnFailure=True,
+            description=["configure"],
+            workdir="build",
+            env=merged_env,
+            doStepIf=FileDoesNotExist("CMakeCache.txt"),
+        )
+    )
+
+    # Build.
+    f.addStep(
+        NinjaCommand(
+            name="Build",
+            targets=["llvm-toolchain"],
+            haltOnFailure=True,
+            description=["build"],
+            workdir="build",
+            env=merged_env,
+        )
+    )
+
+    # Test.
+    f.addStep(
+        NinjaCommand(
+            name="Test",
+            targets=["check-llvm-toolchain"],
+            haltOnFailure=True,
+            description=["check"],
+            workdir="build",
+            env=merged_env,
+            doStepIf=test,
+        )
+    )
+
+    return f