gentoo-overlay/gnome-extra/evolution-data-server/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
	<maintainer type="project">
		<email>gnome@gentoo.org</email>
		<name>Gentoo GNOME Desktop</name>
	</maintainer>
	<use>
		<flag name="api-doc-extras">Build documentation for private APIs</flag>
		<flag name="berkdb"><pkg>sys-libs/db</pkg> support needed to migrate old (pre-3.12 evolution versions) addressbook data</flag>
		<flag name="gnome-online-accounts">Enable using	<pkg>net-libs/gnome-online-accounts</pkg> for authorization</flag>
		<flag name="google">Enable Google Contacts support. This will also enable the internal Google authentication support.
			Please note this last one relies on a deprecated (and vulnerable) <pkg>net-libs/webkit-gtk</pkg> slot.
			If you want to avoid this dependency, you can disable this support and rely on gnome-online-accounts instead</flag>
		<flag name="weather">Enable optional weather calendar support</flag>
	</use>
</pkgmetadata>