diff --git a/.gitmodules b/.gitmodules
index 32bdb3b6e5a68a1a06d685b9fe830d242cae097d..90d1be0a3d1073e84007cb0d15872ad40a617c0b 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,4 @@
 [submodule "tests"]
 	path = tests/testdata
 	url = https://github.com/ethereum/tests
+	shallow = true