diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..438e86a
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "zlib"]
+	path = zlib
+	url = git@github.com:madler/zlib.git
diff --git a/zlib b/zlib
new file mode 160000
index 0000000..04f42ce
--- /dev/null
+++ b/zlib
@@ -0,0 +1 @@
+Subproject commit 04f42ceca40f73e2978b50e93806c2a18c1281fc