diff --git a/dev-python/pynacl/pynacl-1.2.1.ebuild b/dev-python/pynacl/pynacl-1.2.1.ebuild
index 730a7c34145cd..7d9759f68b5e8 100644
--- a/dev-python/pynacl/pynacl-1.2.1.ebuild
+++ b/dev-python/pynacl/pynacl-1.2.1.ebuild
@@ -13,7 +13,7 @@ SRC_URI="https://github.com/pyca/${PN}/archive/${PV}.tar.gz -> ${P}.tar.gz"
 
 LICENSE="Apache-2.0"
 SLOT="0"
-KEYWORDS="~amd64 ~arm ~hppa ~ia64 ~ppc ~ppc64 ~x86 ~amd64-fbsd"
+KEYWORDS="~amd64 ~arm ~hppa ~ia64 ~ppc ~ppc64 ~s390 ~x86 ~amd64-fbsd"
 IUSE="test"
 
 RDEPEND="