diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..caccb04
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "third_party/abseil-cpp"]
+	path = third_party/abseil-cpp
+	url = https://github.com/abseil/abseil-cpp.git