diff --git a/Makefile b/Makefile
index 8d854c4..b98a9cc 100644
--- a/Makefile
+++ b/Makefile
@@ -1,9 +1,9 @@
 PACKAGE	= libApp
 VERSION	= 0.1.5
 SUBDIRS	= data include src tools
-RM	= rm -f
-LN	= ln -f
-TAR	= tar -czvf
+RM	?= rm -f
+LN	?= ln -f
+TAR	?= tar -czvf
 
 
 all: subdirs
diff --git a/data/Makefile b/data/Makefile
index f1baa9c..9080bb0 100644
--- a/data/Makefile
+++ b/data/Makefile
@@ -1,10 +1,10 @@
 TARGETS	= libApp.pc
 PREFIX	= /usr/local
 DESTDIR	=
-RM	= rm -f
-LN	= ln -f
-MKDIR	= mkdir -p
-INSTALL	= install
+RM	?= rm -f
+LN	?= ln -f
+MKDIR	?= mkdir -p
+INSTALL	?= install
 
 
 all: $(TARGETS)
diff --git a/include/System/App/Makefile b/include/System/App/Makefile
index d4d3dd9..03de9f6 100644
--- a/include/System/App/Makefile
+++ b/include/System/App/Makefile
@@ -1,9 +1,9 @@
 PREFIX	= /usr/local
 DESTDIR	=
-RM	= rm -f
-LN	= ln -f
-MKDIR	= mkdir -p
-INSTALL	= install
+RM	?= rm -f
+LN	?= ln -f
+MKDIR	?= mkdir -p
+INSTALL	?= install
 INCLUDEDIR= $(PREFIX)/include
 
 
diff --git a/include/System/Makefile b/include/System/Makefile
index b0190f6..0bf7dd3 100644
--- a/include/System/Makefile
+++ b/include/System/Makefile
@@ -1,10 +1,10 @@
 SUBDIRS	= App
 PREFIX	= /usr/local
 DESTDIR	=
-RM	= rm -f
-LN	= ln -f
-MKDIR	= mkdir -p
-INSTALL	= install
+RM	?= rm -f
+LN	?= ln -f
+MKDIR	?= mkdir -p
+INSTALL	?= install
 INCLUDEDIR= $(PREFIX)/include
 
 
diff --git a/src/Makefile b/src/Makefile
index 0c2aa9c..6d7ba5d 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -8,13 +8,13 @@ CPPFLAGS= -I $(PREFIX)/include -D WITH_SSL
 CFLAGSF	= -W -fPIC `pkg-config --cflags libSystem`
 CFLAGS	= -Wall -g -O2 -pedantic
 LDFLAGS	= -lssl
-AR	= ar -rc
-RANLIB	= ranlib
-LD	= $(CC) -shared
-RM	= rm -f
-LN	= ln -f
-MKDIR	= mkdir -p
-INSTALL	= install
+AR	?= ar
+RANLIB	?= ranlib
+CCSHARED?= $(CC) -shared
+RM	?= rm -f
+LN	?= ln -f
+MKDIR	?= mkdir -p
+INSTALL	?= install
 
 
 all: $(TARGETS)
@@ -24,11 +24,11 @@ libApp_CFLAGS = $(CPPFLAGSF) $(CPPFLAGS) $(CFLAGSF) $(CFLAGS)
 libApp_LDFLAGS = $(LDFLAGSF) $(LDFLAGS) `pkg-config --libs libSystem`  
 
 libApp.a: $(libApp_OBJS)
-	$(AR) libApp.a $(libApp_OBJS)
+	$(AR) -rc libApp.a $(libApp_OBJS)
 	$(RANLIB) libApp.a
 
 libApp.so: $(libApp_OBJS)
-	$(LD) -o libApp.so -Wl,-soname,libApp.so.0 $(libApp_OBJS) $(libApp_LDFLAGS)
+	$(CCSHARED) -o libApp.so -Wl,-soname,libApp.so.0 $(libApp_OBJS) $(libApp_LDFLAGS)
 
 appclient.o: appclient.c appinterface.h ../include/System/App/appclient.h
 	$(CC) $(libApp_CFLAGS) -c appclient.c
diff --git a/tools/Makefile b/tools/Makefile
index 0d087b4..ac1061a 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -9,10 +9,10 @@ CFLAGSF	= -W `pkg-config --cflags libSystem`
 CFLAGS	= -Wall -g -O2 -pedantic
 LDFLAGSF= -L../src `pkg-config --libs libSystem` -lApp
 LDFLAGS	= -L$(PREFIX)/lib -Wl,-rpath,$(PREFIX)/lib
-RM	= rm -f
-LN	= ln -f
-MKDIR	= mkdir -p
-INSTALL	= install
+RM	?= rm -f
+LN	?= ln -f
+MKDIR	?= mkdir -p
+INSTALL	?= install
 
 
 all: $(TARGETS)