--- a/runtime/Makefile.unix	2024-06-17 10:03:13.524360767 +0200
+++ b/runtime/Makefile.unix	2024-06-17 10:03:55.768905814 +0200
@@ -26,10 +26,10 @@
 #	$(RANLIB) $@
 
 install:
-	cp camlidlruntime.h $(OCAMLLIB)/caml/camlidlruntime.h
-	cp libcamlidl.a $(OCAMLLIB)/libcamlidl.a
-	cp dllcamlidl.so $(OCAMLLIB)/stublibs/dllcamlidl.so
-	cd $(OCAMLLIB); $(RANLIB) libcamlidl.a
+	cp camlidlruntime.h $(DESTDIR)$(OCAMLLIB)/caml/camlidlruntime.h
+	cp libcamlidl.a $(DESTDIR)$(OCAMLLIB)/libcamlidl.a
+	cp dllcamlidl.so $(DESTDIR)$(OCAMLLIB)/stublibs/dllcamlidl.so
+	cd $(DESTDIR)$(OCAMLLIB); $(RANLIB) libcamlidl.a
 
 clean:
 	rm -f *.a *.o *.so
--- a/lib/Makefile	2024-06-17 10:06:49.145036983 +0200
+++ b/lib/Makefile	2024-06-17 10:07:44.366441218 +0200
@@ -40,10 +40,10 @@
 	$(OCAMLOPT) -a -o $(NATIVELIB) -cclib -lcamlidl $(NATIVEOBJS)
 
 installbyt:
-	cp -p $(INTERFACES) $(BYTELIB) $(OCAMLLIB)
+	cp -p $(INTERFACES) $(BYTELIB) $(DESTDIR)$(OCAMLLIB)
 
 installopt:
-	cp -p $(NATIVELIB) $(NATIVELIB:.cmxa=.$(LIBEXT)) $(OCAMLLIB)
+	cp -p $(NATIVELIB) $(NATIVELIB:.cmxa=.$(LIBEXT)) $(DESTDIR)$(OCAMLLIB)
 
 .SUFFIXES: .mli .ml .cmi .cmo .cmx