diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3376817..1342a97 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -27,6 +27,7 @@ jobs:
           sudo apt-get install make -y
           git clone git@github.com:protocolbuffers/protobuf.git
           cd protobuf
+          git submodule update --init --recursive
           cmake .
           cmake --build . --parallel 10
           ctest --verbose