diff --git a/Makefile b/Makefile
index 35d2a0add2..2cc95b98bf 100644
--- a/Makefile
+++ b/Makefile
@@ -144,7 +144,7 @@ static: cockpit tmtc generators sim_static joystick static_h
 
 libpprzlink:
 	$(MAKE) -C $(EXT) pprzlink.update
-	$(Q)Q=$(Q) DESTDIR=$(PPRZLINK_INSTALL) PPRZLINK_LIB_VERSION=${PPRZLINK_LIB_VERSION} $(MAKE) -C $(PPRZLINK_DIR) libpprzlink-install
+	$(Q)Q=$(Q) MAKEFLAGS=-j1 DESTDIR=$(PPRZLINK_INSTALL) PPRZLINK_LIB_VERSION=${PPRZLINK_LIB_VERSION} $(MAKE) -C $(PPRZLINK_DIR) libpprzlink-install
 
 libpprz: libpprzlink _save_build_version
 	$(MAKE) -C $(LIB)/ocaml
@@ -184,7 +184,7 @@ subdirs: $(SUBDIRS)
 
 $(MISC): ext
 
-$(SUBDIRS):
+$(SUBDIRS): libpprz
 	$(MAKE) -C $@
 
 $(PPRZCENTER): libpprz
@@ -193,7 +193,7 @@ $(LOGALIZER): libpprz
 
 static_h: pprzlink_protocol $(GEN_HEADERS)
 
-pprzlink_protocol :
+pprzlink_protocol : libpprz
 	$(Q)test -d $(STATICINCLUDE) || mkdir -p $(STATICINCLUDE)
 	$(Q)test -d $(STATICLIB) || mkdir -p $(STATICLIB)
 ifeq ("$(wildcard $(CUSTOM_MESSAGES_XML))","")
diff --git a/sw/lib/ocaml/Makefile b/sw/lib/ocaml/Makefile
index 174c3bcff7..bafdce6f71 100644
--- a/sw/lib/ocaml/Makefile
+++ b/sw/lib/ocaml/Makefile
@@ -123,8 +123,12 @@ xlib-pprz.cmxa dllxlib-pprz.so: $(XCMX)
 
 # trying to set correct dependencies for parallel build
 # these are order only depedencies
+lib-pprz.cma: | liblib-pprz.a dlllib-pprz.so
+
 lib-pprz.cmxa: | liblib-pprz.a dlllib-pprz.so
 
+xlib-pprz.cma: | libxlib-pprz.a dllxlib-pprz.so
+
 xlib-pprz.cmxa: | libxlib-pprz.a dllxlib-pprz.so
 
 xml_get.cmo : xml_get.ml lib-pprz.cma