diff --git a/.gitmodules b/.gitmodules
index abb75c5..e04558d 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,6 +1,9 @@
 [submodule "third-party/Criterion"]
 	path = third-party/Criterion
 	url = https://github.com/Snaipe/Criterion.git
 [submodule "third-party/pybind11"]
 	path = third-party/pybind11
 	url = https://github.com/pybind/pybind11.git
+[submodule "third-party/googletest"]
+	path = third-party/googletest
+	url = https://github.com/google/googletest.git
diff --git a/third-party/googletest b/third-party/googletest
new file mode 160000
index 0000000..f35fe6d
--- /dev/null
+++ b/third-party/googletest
@@ -0,0 +1 @@
+Subproject commit f35fe6de3b25671099de0bf69b016eed3832dc9e