diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..97245ae
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "src/external/xxhash"]
+	path = src/external/xxhash
+	url = https://github.com/Cyan4973/xxHash.git
diff --git a/src/external/xxhash b/src/external/xxhash
new file mode 160000
index 0000000..38d5558
--- /dev/null
+++ b/src/external/xxhash
@@ -0,0 +1 @@
+Subproject commit 38d555879fddae7300ece2c0820b3332c1d5748f