diff --git a/src/wasm-sample/Makefile b/src/wasm-sample/Makefile
index 1f1704e6a..d072e1e50 100644
--- a/src/wasm-sample/Makefile
+++ b/src/wasm-sample/Makefile
@@ -12,7 +12,7 @@ all: test.wasm.ttf
 		-o $@
 
 %.wasm.ttf: %.ttf shape.so addTable.py
-	python addTable.py
+	python addTable.py $< $@ shape.so
 
 clean:
 	$(RM) test.wasm.ttf shape.so
diff --git a/src/wasm-sample/addTable.py b/src/wasm-sample/addTable.py
index f8e38858e..103f292dd 100644
--- a/src/wasm-sample/addTable.py
+++ b/src/wasm-sample/addTable.py
@@ -1,11 +1,16 @@
+import sys
 from fontTools.ttLib import TTFont
 from fontTools.ttLib.tables.DefaultTable import DefaultTable
 
-font = TTFont("test.ttf")
+if len(sys.argv) == 1:
+    print("usage: python addTable.py input.ttf output.ttf Wasm.bin")
+    sys.exit(1)
+
+font = TTFont(sys.argv[1])
 
 wasm_table = DefaultTable("Wasm")
-wasm_table.data = open("shape.so", "rb").read()
+wasm_table.data = open(sys.argv[3], "rb").read()
 
 font["Wasm"] = wasm_table
 
-font.save("test.wasm.ttf")
+font.save(sys.argv[2])
diff --git a/src/wasm-sample/test.ttf b/src/wasm-sample/test.ttf
index 2ba04f611..2a5535f5f 100644
Binary files a/src/wasm-sample/test.ttf and b/src/wasm-sample/test.ttf differ