diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..53d7ecd
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "external/google-test"]
+	path = external/google-test
+	url = https://github.com/google/googletest.git
diff --git a/external/google-test b/external/google-test
new file mode 160000
index 0000000..ecd5308
--- /dev/null
+++ b/external/google-test
@@ -0,0 +1 @@
+Subproject commit ecd530865cefdfa7dea58e84f6aa1b548950363d