--- Makefile
+++ Makefile
@@ -28,16 +28,16 @@
 install: install-libnut install-nututils
 
 install-libnut: libnut install-libnut-headers
-	install -d $(prefix)/lib
-	install -m 644 libnut/libnut.a $(prefix)/lib
+	install -d $(libdir)
+	install -m 644 libnut/libnut.a $(libdir)
 
 install-libnut-shared: libnut/libnut.so install-libnut-headers
-	install -d $(prefix)/lib
-	install -m 644 libnut/libnut.so $(prefix)/lib
+	install -d $(libdir)
+	install -m 644 libnut/libnut.so $(libdir)
 
 install-libnut-headers:
-	install -d $(prefix)/include
-	install -m 644 libnut/libnut.h $(prefix)/include
+	install -d $(includedir)
+	install -m 644 libnut/libnut.h $(includedir)
 
 install-nututils: nututils
 	install -d $(prefix)/bin
@@ -46,9 +46,9 @@
 uninstall: uninstall-libnut uninstall-nututils
 
 uninstall-libnut:
-	rm -f $(prefix)/lib/libnut.a
-	rm -f $(prefix)/lib/libnut.so
-	rm -f $(prefix)/include/libnut.h
+	rm -f $(libdir)/libnut.a
+	rm -f $(libdir)/libnut.so
+	rm -f $(includedir)/libnut.h
 
 uninstall-nututils:
 	rm -f $(addprefix $(prefix)/bin/, $(subst nututils/,,$(NUTUTILS_PROGS)))
--- config.mak
+++ config.mak
@@ -1,5 +1,7 @@
 PREFIX = /usr/local
 prefix = $(DESTDIR)$(PREFIX)
+libdir = $(prefix)/lib
+includedir = $(prefix)/include
 
 #CFLAGS += -DDEBUG