diff --git a/programs/demos/kmatrix/trunk/Tupfile.lua b/programs/demos/kmatrix/trunk/Tupfile.lua
index e552d22b33..f275852cda 100755
--- a/programs/demos/kmatrix/trunk/Tupfile.lua
+++ b/programs/demos/kmatrix/trunk/Tupfile.lua
@@ -1,10 +1,8 @@
 if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("HELPERDIR") == ""
+then
+  HELPERDIR = "../../../../programs"
+end
+tup.include(HELPERDIR .. "/use_tcc.lua")
 
-TCC="kos32-tcc"
-CFLAGS  = "-I../../../develop/ktcc/trunk/libc.obj/include"
-LDFLAGS = "-nostdlib ../../../develop/ktcc/trunk/bin/lib/crt0.o -L../../../develop/ktcc/trunk/bin/lib"
-LIBS = "-ltcc -lc.obj"
-
-COMMAND=string.format("%s %s %s %s %s", TCC, CFLAGS, LDFLAGS , "%f -o %o",  LIBS)
-
-tup.rule({"main.c"}, COMMAND .. tup.getconfig("KPACK_CMD"), "kmatrix")
\ No newline at end of file
+link_tcc("main.c", "kmatrix");