diff --git a/math/moab/Makefile b/math/moab/Makefile
index 82eda331ad5c..6f6471814442 100644
--- a/math/moab/Makefile
+++ b/math/moab/Makefile
@@ -1,47 +1,46 @@
 PORTNAME=	moab
 DISTVERSION=	5.3.1
 PORTREVISION=	1
 CATEGORIES=	math
 MASTER_SITES=	https://bitbucket.org/${BB_ACCOUNT}/${BB_PROJECT}/get/${BB_COMMIT}.tar.gz?dummy=/
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Component for representing and evaluating mesh data
 
 LICENSE=	LGPL3+
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 LIB_DEPENDS=	libhdf5.so:science/hdf5 \
 		libnetcdf.so:science/netcdf \
 		libopenblas.so:math/openblas
 
 USES=		cmake eigen:3 fortran
 USE_LDCONFIG=	yes
 
 CMAKE_ARGS=	-DBLAS_LIBRARIES:STRING=${LOCALBASE}/lib/libopenblas.so \
 		-DLAPACK_LIBRARIES:STRING=${LOCALBASE}/lib/libopenblas.so \
 		-DFREEBSD_STAGEDIR:STRING=${STAGEDIR}
 
 BB_ACCOUNT=	fathomteam
 BB_PROJECT=	${PORTNAME}
 BB_COMMIT=	65880ffe833d
 
 WRKSRC=		${WRKDIR}/${BB_ACCOUNT}-${BB_PROJECT}-${BB_COMMIT}
 
 OPTIONS_DEFINE=		MPI
 OPTIONS_DEFAULT=	MPI
 OPTIONS_SUB=		yes
 
 MPI_CMAKE_BOOL=		ENABLE_MPI
 MPI_LIB_DEPENDS=	libmpi.so:net/openmpi
-MPI_LDFLAGS=		-L${LOCALBASE}/mpi/openmpi/lib
 MPI_VARS=		CXX=${LOCALBASE}/mpi/openmpi/bin/mpic++ CC=${LOCALBASE}/mpi/openmpi/bin/mpicc
-MPI_VARS=		CONFLICTS_BUILD=mpich # otherwise bin/hexmodops gets linked with libmpi.so:net/mpich
+MPI_VARS+=		CONFLICTS_BUILD=mpich # otherwise bin/hexmodops gets linked with libmpi.so:net/mpich
 MPI_VARS_OFF=		USES=compiler:c++11-lang
 
 post-install:
 	# docs are just readmes
 	@${RM} -r ${STAGEDIR}${DOCSDIR}
 	# examples are installed into a wrong location, maybe fix them later?
 	@${RM} -r ${STAGEDIR}${PREFIX}/share/examples
 
 .include <bsd.port.mk>