diff --git a/.github/workflows/wpt.yml b/.github/workflows/wpt.yml
index 1e11e46a..a5b8ee69 100644
--- a/.github/workflows/wpt.yml
+++ b/.github/workflows/wpt.yml
@@ -32,7 +32,8 @@ jobs:
         with:
           fetch-depth: 0
           token: ${{ secrets.GH_CI_PAT }}
-          submodules: true
+          # fetch submodules recusively, to get jsruntime-lib submodules also.
+          submodules: recursive
 
       - name: install v8
         run: |
diff --git a/.github/workflows/zig-test.yml b/.github/workflows/zig-test.yml
index 01972d41..4b33e4cd 100644
--- a/.github/workflows/zig-test.yml
+++ b/.github/workflows/zig-test.yml
@@ -31,7 +31,8 @@ jobs:
         with:
           fetch-depth: 0
           token: ${{ secrets.GH_CI_PAT }}
-          submodules: true
+          # fetch submodules recusively, to get jsruntime-lib submodules also.
+          submodules: recursive
 
       - name: install v8
         run: |