diff --git a/libmuscle/cpp/build/Makefile b/libmuscle/cpp/build/Makefile
index 910e4854..c6cdcbd6 100644
--- a/libmuscle/cpp/build/Makefile
+++ b/libmuscle/cpp/build/Makefile
@@ -27,10 +27,10 @@ distclean:
 
 # Find dependencies or set up build
 
-dep_name := msgpack
-dep_version_constraint := >= 3.2.0
-dep_version := 3.2.0
-dep_pkgconfig_name := msgpack
+dep_name := messagepack
+dep_version_constraint := >= 7.0.0
+dep_version := 7.0.0
+dep_pkgconfig_name := msgpack-cxx
 dep_install := 1
 include $(TOOLDIR)/make_available.make
 
@@ -46,7 +46,7 @@ include $(TOOLDIR)/make_available.make
 DEP_DIRS += $(CURDIR)/msgpack/msgpack
 export DEP_DIRS
 
-PKG_CONFIG_EXTRA_DIRS := $(PKG_CONFIG_EXTRA_DIRS):$(CURDIR)/msgpack/msgpack/lib/pkgconfig
+PKG_CONFIG_EXTRA_DIRS := $(PKG_CONFIG_EXTRA_DIRS):$(CURDIR)/msgpack/lib/pkgconfig
 export PKG_CONFIG_EXTRA_DIRS
 
 
diff --git a/libmuscle/cpp/build/libmuscle/Makefile b/libmuscle/cpp/build/libmuscle/Makefile
index 71860ac7..89d5af61 100644
--- a/libmuscle/cpp/build/libmuscle/Makefile
+++ b/libmuscle/cpp/build/libmuscle/Makefile
@@ -76,7 +76,7 @@ endif
 
 installed_pkg_config_files := $(pkg_config_files:%=$(PREFIX)/lib/pkgconfig/%)
 
-CXXFLAGS += -Wall -pedantic -std=c++14 -pthread -O3
+CXXFLAGS += -Wall -pedantic -std=c++14 -pthread -O3 -DMSGPACK_NO_BOOST
 export CXXFLAGS
 
 MPIFLAGS := -DMUSCLE_ENABLE_MPI
@@ -136,10 +136,12 @@ install: all $(installed_headers) $(installed_pkg_config_files)
 	-install_name_tool -change libymmsl.dylib @loader_path/libymmsl.dylib $(PREFIX)/lib/libmuscle_d.dylib
 	-install_name_tool -change libymmsl.dylib @loader_path/libymmsl.dylib $(PREFIX)/lib/libmuscle_mpi.dylib
 	-install_name_tool -change libymmsl.dylib @loader_path/libymmsl.dylib $(PREFIX)/lib/libmuscle_mpi_d.dylib
-	install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle.dylib
-	-install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_d.dylib
-	-install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_mpi.dylib
-	-install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_mpi_d.dylib
+
+	# Not needed for MessagePack 7.0.0
+	# install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle.dylib
+	# -install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_d.dylib
+	# -install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_mpi.dylib
+	# -install_name_tool -change @rpath/libmsgpackc.2.dylib @loader_path/libmsgpackc.2.dylib $(PREFIX)/lib/libmuscle_mpi_d.dylib
 	@mkdir -p $(PREFIX)/bin
 	sed -e 's@%PREFIX%@$(PREFIX)@g' muscle3.env.in >$(PREFIX)/bin/muscle3.env
 	for pc in $(PREFIX)/lib/pkgconfig/* ; do sed -i -e 's@^prefix=.*$$@prefix=$(PREFIX)@' $$pc ; done
@@ -152,11 +154,14 @@ ifeq "$(filter $(MAKECMDGOALS),$(cleantargets))" ""
 
 # Dependencies
 $(info pcextra: $(PKG_CONFIG_EXTRA_DIRS))
-CXXFLAGS += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_EXTRA_DIRS):$(PKG_CONFIG_PATH) ; pkg-config --cflags msgpack)
+# MSGPACK_FLAGS := $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_EXTRA_DIRS):$(PKG_CONFIG_PATH) ; pkg-config --cflags msgpack-cxx)
+MSGPACK_INCLUDE_DIR = $(CURDIR)/../msgpack/msgpack/include
+export MSGPACK_INCLUDE_DIR
+CXXFLAGS += -I$(MSGPACK_INCLUDE_DIR)
 
 LDFLAGS2 = $(LDFLAGS)
 LDFLAGS2 += -pthread -L$(CURDIR)/../ymmsl -lymmsl
-LDFLAGS2 += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_EXTRA_DIRS):$(PKG_CONFIG_PATH) ; pkg-config --libs msgpack)
+# LDFLAGS2 += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_EXTRA_DIRS):$(PKG_CONFIG_PATH) ; pkg-config --libs msgpack-cxx-cxx)
 
 # Automatic header dependencies
 -include $(deps)
@@ -284,9 +289,9 @@ libmuscle.pc:
 	@echo 'URL: https://muscle3.readthedocs.io' >>$@
 	@echo 'Version: $(muscle_version)' >>$@
 	@echo 'Requires: ymmsl = $(muscle_version)' >>$@
-	@echo 'Requires.private: msgpack >= 3.1.0' >>$@
-	@echo 'Cflags: -I$${includedir} -pthread' >>$@
-	@echo 'Cflags.private: -pthread' >>$@
+	@echo 'Requires.private:' >>$@
+	@echo 'Cflags: -I$${includedir} -pthread -DMSGPACK_NO_BOOST' >>$@
+	@echo 'Cflags.private: -pthread -DMSGPACK_NO_BOOST' >>$@
 	@echo 'Libs: -L$${libdir} -lmuscle' >>$@
 	@echo 'Libs.private: -pthread' >>$@
 
@@ -301,8 +306,8 @@ libmuscle_mpi.pc:
 	@echo 'URL: https://muscle3.readthedocs.io' >>$@
 	@echo 'Version: $(muscle_version)' >>$@
 	@echo 'Requires: ymmsl = $(muscle_version)' >>$@
-	@echo 'Requires.private: msgpack >= 3.1.0' >>$@
-	@echo 'Cflags: -I$${includedir} -pthread -DMUSCLE_ENABLE_MPI' >>$@
-	@echo 'Cflags.private: -pthread' >>$@
+	@echo 'Requires.private:' >>$@
+	@echo 'Cflags: -I$${includedir} -pthread -DMUSCLE_ENABLE_MPI -DMSGPACK_NO_BOOST' >>$@
+	@echo 'Cflags.private: -pthread -DMSGPACK_NO_BOOST' >>$@
 	@echo 'Libs: -L$${libdir} -lmuscle_mpi' >>$@
 	@echo 'Libs.private: -pthread' >>$@
diff --git a/libmuscle/cpp/build/libmuscle/tests/Makefile b/libmuscle/cpp/build/libmuscle/tests/Makefile
index 387dea44..05afad61 100644
--- a/libmuscle/cpp/build/libmuscle/tests/Makefile
+++ b/libmuscle/cpp/build/libmuscle/tests/Makefile
@@ -47,14 +47,15 @@ ifeq "$(filter $(MAKECMDGOALS),$(cleantargets))" ""
 EXTRA_LINK_DIRS := $(foreach DIR,$(DEP_DIRS),-Wl,-rpath,$(DIR)/lib)
 
 CXXFLAGS += -I$(libmuscle_testdir) -isystem $(googletest_ROOT)/include -pthread
-CXXFLAGS += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_PATH):$(PKG_CONFIG_EXTRA_DIRS) ; pkg-config --cflags msgpack)
+# CXXFLAGS += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_PATH):$(PKG_CONFIG_EXTRA_DIRS) ; pkg-config --cflags msgpack) # Keep this line anyways, may need it
+CXXFLAGS += -I$(MSGPACK_INCLUDE_DIR)
 CXXFLAGS += -DTESTING $(DEBUGFLAGS)
 
 LDFLAGS += $(CURDIR)/../libmuscle_d.a $(CURDIR)/../../ymmsl/libymmsl_d.a
 LDFLAGS += $(googletest_LIB) -pthread
 
 LDFLAGS2 := $(LDFLAGS)
-LDFLAGS2 += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_PATH):$(PKG_CONFIG_EXTRA_DIRS) ; pkg-config --libs msgpack)
+# LDFLAGS2 += $(shell export PKG_CONFIG_PATH=$(PKG_CONFIG_PATH):$(PKG_CONFIG_EXTRA_DIRS) ; pkg-config --libs msgpack)
 LDFLAGS2 += $(EXTRA_LINK_DIRS)
 
 -include $(deps)
diff --git a/libmuscle/cpp/build/msgpack/Makefile b/libmuscle/cpp/build/msgpack/Makefile
index 3ad756a0..5c3b6047 100644
--- a/libmuscle/cpp/build/msgpack/Makefile
+++ b/libmuscle/cpp/build/msgpack/Makefile
@@ -3,8 +3,8 @@ all: msgpack
 
 .PHONY: install
 install: msgpack
-	mkdir -p $(PREFIX)/lib
-	cp -a msgpack/lib/* $(PREFIX)/lib/
+	# mkdir -p $(PREFIX)/lib
+	# cp -a msgpack/lib/* $(PREFIX)/lib/  # Commented: MessagePack 7.0.0 is header-only
 	mkdir -p $(PREFIX)/include
 	cp -a msgpack/include/* $(PREFIX)/include/
 
@@ -17,28 +17,29 @@ distclean: clean
 	rm -rf $$(find . -type d -name 'msgpack-*')
 	rm -rf msgpack
 
-MSGPACK_LIB=$(CURDIR)/msgpack/lib/libmsgpackc.a
-MSGPACK_SRC=$(CURDIR)/msgpack-$(msgpack_VERSION)/ChangeLog
+# MSGPACK_LIB=$(CURDIR)/msgpack/lib/libmsgpackc.a  # Commented: MessagePack 7.0.0 is header-only
+MSGPACK_INCLUDE_DIR=$(CURDIR)/msgpack/include
+MSGPACK_SRC=$(CURDIR)/msgpack-cxx-$(msgpack_VERSION)/ChangeLog
 
-msgpack-$(msgpack_VERSION).tar.gz:
-	$(DOWNLOAD) https://github.com/msgpack/msgpack-c/releases/download/cpp-$(msgpack_VERSION)/msgpack-$(msgpack_VERSION).tar.gz
+msgpack-cxx-$(msgpack_VERSION).tar.gz:
+	$(DOWNLOAD) https://github.com/msgpack/msgpack-c/releases/download/cpp-$(msgpack_VERSION)/msgpack-cxx-$(msgpack_VERSION).tar.gz
 
-$(MSGPACK_SRC): msgpack-$(msgpack_VERSION).tar.gz
-	$(TAR) xf msgpack-$(msgpack_VERSION).tar.gz -m
+$(MSGPACK_SRC): msgpack-cxx-$(msgpack_VERSION).tar.gz
+	$(TAR) xf msgpack-cxx-$(msgpack_VERSION).tar.gz -m
 
-$(MSGPACK_LIB): $(MSGPACK_SRC)
-	cd msgpack-$(msgpack_VERSION) && rm -rf build && mkdir -p build && cd build && \
+$(MSGPACK_INCLUDE_DIR): $(MSGPACK_SRC)
+	cd msgpack-cxx-$(msgpack_VERSION) && rm -rf build && mkdir -p build && cd build && \
 		export PKG_CONFIG_PATH=$(PKG_CONFIG_PATH):$(PKG_CONFIG_EXTRA_DIRS) && \
-		cmake -DCMAKE_POLICY_VERSION_MINIMUM=3.5 -DCMAKE_INSTALL_PREFIX=$(CURDIR)/msgpack -DMSGPACK_CXX11=ON -DMSGPACK_BUILD_EXAMPLES=OFF -DMSGPACK_BUILD_TESTS=OFF .. && \
+		cmake -DCMAKE_POLICY_VERSION_MINIMUM=3.5 -DMSGPACK_USE_BOOST=OFF -DCMAKE_INSTALL_PREFIX=$(CURDIR)/msgpack -DMSGPACK_CXX11=ON -DMSGPACK_BUILD_EXAMPLES=OFF -DMSGPACK_BUILD_TESTS=OFF .. && \
 		$(MAKE) -j $(NCORES) && make install
 
 ifdef MUSCLE_LINUX
 
-msgpack: $(MSGPACK_LIB)
+msgpack: $(MSGPACK_INCLUDE_DIR)
 
 else ifdef MUSCLE_MACOS
 
-msgpack: $(MSGPACK_LIB)
-	install_name_tool -id $(CURDIR)/msgpack/lib/libmsgpackc.dylib $(CURDIR)/msgpack/lib/libmsgpackc.dylib
+msgpack: $(MSGPACK_INCLUDE_DIR)
+	# install_name_tool -id $(CURDIR)/msgpack/lib/libmsgpackc.dylib $(CURDIR)/msgpack/lib/libmsgpackc.dylib
 
 endif
diff --git a/libmuscle/cpp/src/libmuscle/data.cpp b/libmuscle/cpp/src/libmuscle/data.cpp
index 66920350..9c13f339 100644
--- a/libmuscle/cpp/src/libmuscle/data.cpp
+++ b/libmuscle/cpp/src/libmuscle/data.cpp
@@ -1097,5 +1097,4 @@ DataConstRef DataConstRef::grid_data_<bool>(
     }
 }
 
-} }  // namespace libmuscle::_MUSCLE_IMPL_NS
-
+} }  // namespace libmuscle::_MUSCLE_IMPL_NS
\ No newline at end of file
diff --git a/libmuscle/cpp/src/libmuscle/mpp_message.cpp b/libmuscle/cpp/src/libmuscle/mpp_message.cpp
index 71b6a644..fb3bc944 100644
--- a/libmuscle/cpp/src/libmuscle/mpp_message.cpp
+++ b/libmuscle/cpp/src/libmuscle/mpp_message.cpp
@@ -109,4 +109,3 @@ DataConstRef MPPMessage::as_dict_() const {
 }
 
 } }
-
diff --git a/libmuscle/cpp/src/libmuscle/tests/test_communicator.cpp b/libmuscle/cpp/src/libmuscle/tests/test_communicator.cpp
index c20dfbdc..1ab32d7a 100644
--- a/libmuscle/cpp/src/libmuscle/tests/test_communicator.cpp
+++ b/libmuscle/cpp/src/libmuscle/tests/test_communicator.cpp
@@ -385,4 +385,3 @@ TEST_F(libmuscle_communicator2, test_shutdown) {
 
     ASSERT_TRUE(expected_receivers.empty());
 }
-