gentoo-overlay/app-misc/mime-types/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
<maintainer type="person">
  <email>eras@gentoo.org</email>
  <name>Eray Aslan</name>
</maintainer>
<use>
  <flag name="nginx">Enable mime-types support for
    <pkg>www-servers/nginx</pkg> package</flag>
</use>
</pkgmetadata>