diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..50aaad5
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "zlib-win-build"]
+	path = zlib-win-build
+	url = https://github.com/kiyolee/zlib-win-build.git
diff --git a/zlib-win-build b/zlib-win-build
new file mode 160000
index 0000000..48e49de
--- /dev/null
+++ b/zlib-win-build
@@ -0,0 +1 @@
+Subproject commit 48e49de94a66b0e3cecee38530993bd0c1de5bfa