diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7034158b14e696bc01d2e10815c00e1654f8a350..37de3b9e3c19949d5212153a51c813ac7563b332 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -17,7 +17,7 @@ firmware:
   stage: build
   image: nixos/nix:latest
   variables:
-    GIT_SUBMODULE_STRATEGY: normal
+    GIT_SUBMODULE_STRATEGY: recursive
   script:
     - nix-channel --add https://nixos.org/channels/nixos-19.03 nixpkgs
     - nix-channel --update