diff --git a/Makefile b/Makefile
index 79602e2..11bf8b2 100644
--- a/Makefile
+++ b/Makefile
@@ -1,8 +1,9 @@
-LIBNAME=libtcap
-VERSION=0
+export LIBNAME=libtcap
+export VERSION=0
+export LIBSO=$(LIBNAME).so
+export LIBSOVER=$(LIBNAME).so.$(VERSION)
 
 LIBDIR=lib
-LIB=src/$(LIBNAME).so.$(VERSION)
 HDR=include/tcap
 
 DESTDIR?=/usr/local
@@ -26,7 +27,7 @@ install: all
 	mkdir -p $(DESTDIR)/$(HDR)
 	cp include/*.h $(DESTDIR)/$(HDR)
 	mkdir -p $(DESTDIR)/$(LIBDIR)
-	cp $(LIB) $(DESTDIR)/$(LIBDIR)/$(LIBNAME).so.$(VERSION)
-	ln -s $(LIBNAME).so.$(VERSION) $(DESTDIR)/$(LIBDIR)/$(LIBNAME).so
+	cp src/$(LIBSOVER) $(DESTDIR)/$(LIBDIR)/$(LIBSOVER)
+	ln -s $(LIBSOVER) $(DESTDIR)/$(LIBDIR)/$(LIBSO)
 
-.PHONY: all regenerate-asn1 clean
+.PHONY: all regenerate-asn1 clean install
diff --git a/src/Makefile b/src/Makefile
index 8680c42..334f73e 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,6 +1,3 @@
-LIBNAME=libtcap
-VERSION=0
-
 CC=gcc
 CFLAGS+=-I../asn1-compiled -I../include -g -Wall -O3 -fPIC
 LDFLAGS=-O3 -shared -fPIC -Wl,-soname,$(LIBNAME).so.$(VERSION)
@@ -11,15 +8,15 @@ OBJS=tcap.o
 .PHONY: all clean
 
 
-all: $(LIBNAME).so
+all: $(LIBSO)
 
-$(LIBNAME).so.$(VERSION): $(OBJS) ../asn1-compiled/libtcap-asn.a
+$(LIBSOVER): $(OBJS) ../asn1-compiled/libtcap-asn.a
 	$(CC) -o $@ $(OBJS) ../asn1-compiled/libtcap-asn.a $(LDFLAGS)
 
-$(LIBNAME).so: $(LIBNAME).so.$(VERSION)
-	ln -fs $(LIBNAME).so.$(VERSION) $(LIBNAME).so
+$(LIBSO): $(LIBSOVER)
+	ln -fs $(LIBSOVER) $(LIBSO)
 
 clean:
 	rm -f $(OBJS)
-	rm -f $(LIBNAME).so
-	rm -f $(LIBNAME).so.$(VERSION)
+	rm -f $(LIBSO)
+	rm -f $(LIBSOVER)