diff --git a/x11/contour/Makefile b/x11/contour/Makefile
index ed0de1b7763c..20b5b5db1306 100644
--- a/x11/contour/Makefile
+++ b/x11/contour/Makefile
@@ -1,77 +1,84 @@
 PORTNAME=	contour
 DISTVERSIONPREFIX=	v
 DISTVERSION=	0.6.2.8008
 PORTREVISION=	1
 CATEGORIES=	x11
 
 PATCH_SITES=	https://github.com/${GH_ACCOUNT}/${GH_PROJECT}/commit/
 PATCHFILES=	c2d1ad278972278fb068e5f41ac82bed92c62193.patch:-p1
 
 MAINTAINER=	tagattie@FreeBSD.org
 COMMENT=	Modern C++ terminal emulator
 WWW=		https://contour-terminal.org/
 
 LICENSE=	APACHE20
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
 BUILD_DEPENDS=	${LOCALBASE}/lib/cmake/boxed-cpp/boxed-cpp-config.cmake:devel/boxed-cpp \
 		${LOCALBASE}/lib/cmake/reflection-cpp/reflection-cpp-config.cmake:devel/reflection-cpp \
 		${LOCALBASE}/share/cmake/Microsoft.GSL/Microsoft.GSLConfig.cmake:devel/microsoft-gsl \
 		${LOCALBASE}/lib/cmake/range-v3/range-v3-config.cmake:devel/range-v3
 LIB_DEPENDS=	libunicode.so:devel/libunicode-contour \
 		libyaml-cpp.so:devel/yaml-cpp \
 		libfreetype.so:print/freetype2 \
 		libharfbuzz.so:print/harfbuzz \
 		libssh2.so:security/libssh2 \
 		libfontconfig.so:x11-fonts/fontconfig
 TEST_DEPENDS=	${LOCALBASE}/lib/cmake/Catch2/Catch2Config.cmake:devel/catch2
 
-USES=		cmake:testing desktop-file-utils gl gnome pkgconfig qt:6 xorg
+USES=		cmake:testing compiler desktop-file-utils gl gnome pkgconfig \
+		qt:6 xorg
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	contour-terminal
 
 USE_XORG=	xcb
 USE_GL=		opengl
 USE_GNOME=	cairo
 USE_QT=		base declarative multimedia tools:build
 
 CMAKE_ON=		CONTOUR_INSTALL_TOOLS
 CMAKE_TESTING_ON=	CONTOUR_TESTING
 
 PORTDOCS=	README.md SECURITY.md
 
 OPTIONS_DEFINE=	DOCS
 
 .include <bsd.port.options.mk>
 
 .if ${OPSYS} == FreeBSD && ${ARCH} == i386
 EXTRA_PATCHES=	${PATCHDIR}/extra-patch-src_crispy_read__selector.h
 .endif
 
 # FreeBSD 13 does not have tic in base, so we need one from ports
 .if ${OPSYS} == FreeBSD && ${OSREL:R} == 13
 BUILD_DEPENDS+=	tic:devel/ncurses
 .endif
 
 .if ${ARCH:Mpowerpc*}
 USES+=		compiler:gcc-c++11-lib
 .endif
 
 post-install:
 	@${RM} -r ${STAGEDIR}${DATADIR}
 	@${MKDIR} ${STAGEDIR}${PREFIX}/etc/bash_completion.d \
 		${STAGEDIR}${PREFIX}/share/fish/vendor_completions.d \
 		${STAGEDIR}${PREFIX}/share/zsh/site-functions
 	${INSTALL_DATA} ${WRKSRC}/src/contour/shell-integration/shell-integration.bash \
 		${STAGEDIR}${PREFIX}/etc/bash_completion.d/${PORTNAME}
 	${INSTALL_DATA} ${WRKSRC}/src/contour/shell-integration/shell-integration.fish \
 		${STAGEDIR}${PREFIX}/share/fish/vendor_completions.d/${PORTNAME}.fish
 	${INSTALL_DATA} ${WRKSRC}/src/contour/shell-integration/shell-integration.zsh \
 		${STAGEDIR}${PREFIX}/share/zsh/site-functions/_${PORTNAME}
 
 post-install-DOCS-on:
 	@${MKDIR} ${STAGEDIR}${DOCSDIR}
 	${INSTALL_MAN} ${PORTDOCS:S|^|${WRKSRC}/|} ${STAGEDIR}${DOCSDIR}
 
 .include <bsd.port.mk>
+
+# XXX COMPILER_TYPE is defined after USES was already parsed
+.if ${CHOSEN_COMPILER_TYPE} == clang && ${_CCVERSION:M+assertions}
+llvm_ARGS=	build
+.include "${USESDIR}/llvm.mk"
+.endif