gentoo-overlay/sys-kernel/gentoo-kernel-bin/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
	<maintainer type="project">
		<email>dist-kernel@gentoo.org</email>
		<name>Distribution Kernel Project</name>
	</maintainer>
	<use>
		<flag name="generic-uki">
			Install a prebuilt generic initramfs and Unified Kernel Image
			(EXPERIMENTAL).
		</flag>
		<flag name="initramfs">
			Build initramfs along with the kernel.
		</flag>
	</use>
</pkgmetadata>