--- b/www/mod_auth_gssapi/Makefile	
+++ b/www/mod_auth_gssapi/Makefile	
@@ -13,6 +13,7 @@ LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/COPYING
 
 USES=		autoreconf apache:2.4+ bison gssapi:mit,flags libtool ssl
+USES+=		pkgconfig
 USE_GITHUB=	yes
 GH_ACCOUNT=	modauthgssapi
 GNU_CONFIGURE=	yes