diff --git a/src/syncterm/GNUmakefile b/src/syncterm/GNUmakefile
index e142d4b41e29f63d2e842d61e7dadc35ab4233d1..219f62023ecd4369f30c407440c16927eb2dfc6c 100644
--- a/src/syncterm/GNUmakefile
+++ b/src/syncterm/GNUmakefile
@@ -23,3 +23,23 @@ vpath %.c ../sbbs3 ../smblib ../uifc ../guts
 $(SYNCTERM): $(EXEODIR) $(OBJS) $(BUILD_DEPENDS)
 	@echo Linking $@
 	${QUIET}$(CC) $(LDFLAGS) $(MT_LDFLAGS) $(OBJS) -o $@ $(UIFC-MT_LIBS) $(CIOLIB-MT_LIBS) $(XPDEV-MT_LIBS)
+
+devel: tags cscope.out
+
+cscope.out: cscope.files
+	cscope -b
+
+tags: cscope.files
+	exctags -VL cscope.files
+
+cscope.files::
+	find . ../conio ../uifc ../xpdev -name '*.c' -o -name '*.cpp' -o -name '*.h' > cscope.files
+	echo ../sbbs3/telnet.c >> cscope.files
+	echo ../sbbs3/telnet.h >> cscope.files
+	echo ../sbbs3/zmodem.c >> cscope.files
+	echo ../sbbs3/zmodem.h >> cscope.files
+	echo ../sbbs3/xmodem.h >> cscope.files
+	echo ../smblib/crc16.c >> cscope.files
+	echo ../smblib/crc16.h >> cscope.files
+	echo ../smblib/crc32.c >> cscope.files
+	echo ../smblib/crc32.h >> cscope.files