diff --git a/rubygem-glu.spec b/rubygem-glu.spec
index 81e9da9..78340c4 100644
--- a/rubygem-glu.spec
+++ b/rubygem-glu.spec
@@ -24,6 +24,9 @@ BuildRequires:	%{_bindir}/xvfb-run
 BuildRequires:	mesa-dri-drivers
 BuildRequires:	rubygem(opengl) >= 0.9
 BuildRequires:	rubygem(glut)
+%if 0%{?fedora} >= 36
+BuildRequires:	rubygem(matrix)
+%endif
 %endif
 
 %description
@@ -102,6 +105,7 @@ popd
 %changelog
 * Thu Jan 27 2022 Mamoru TASAKA <mtasaka@fedoraproject.org> - 8.3.0-20
 - F-36: rebuild against ruby31
+- F-36: BR: rubygem(matrix) for test suite
 
 * Fri Jan 21 2022 Fedora Release Engineering <releng@fedoraproject.org> - 8.3.0-19
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_36_Mass_Rebuild