diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2c25a3f..3b11ab2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -21,6 +21,8 @@ jobs:
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
       - uses: actions/checkout@v2
+        with:
+          submodules: recursive
       - uses: iffy/install-nim@v3.2.0
         with:
           version: ${{ matrix.nimversion }}