diff --git a/.gitmodules b/.gitmodules
index 9a3356df..d3496c98 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -79,3 +79,6 @@
 [submodule "external/audio-algo-speex"]
 	path = external/audio-algo-speex
 	url = http://github.com/musicdsp/audio-algo-speex.git
+[submodule "external/z"]
+	path = external/z
+	url = https://github.com/HeeroYui/z.git
diff --git a/external/z b/external/z
new file mode 160000
index 00000000..be3dd12f
--- /dev/null
+++ b/external/z
@@ -0,0 +1 @@
+Subproject commit be3dd12fa3b9977b4847ac5889f5257cfd591de5