diff --git a/dev-ruby/memoist3/memoist3-1.0.0.ebuild b/dev-ruby/memoist3/memoist3-1.0.0.ebuild
index 384121ef1daa..88a1c6e44b6a 100644
--- a/dev-ruby/memoist3/memoist3-1.0.0.ebuild
+++ b/dev-ruby/memoist3/memoist3-1.0.0.ebuild
@@ -13,7 +13,7 @@ HOMEPAGE="https://github.com/honzasterba/memoist"
 
 LICENSE="MIT"
 SLOT="0"
-KEYWORDS="~amd64 ~arm ~arm64 ~hppa ~loong ~ppc ~ppc64 ~riscv ~sparc ~x86"
+KEYWORDS="~amd64 ~arm ~arm64 ~hppa ~loong ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86"
 
 ruby_add_bdepend "test? ( dev-ruby/minitest )"