diff --git a/.github/workflows/ci_test.yml b/.github/workflows/ci_test.yml
index 2d31a4a..61579e2 100644
--- a/.github/workflows/ci_test.yml
+++ b/.github/workflows/ci_test.yml
@@ -22,12 +22,14 @@
         with:
           repository: KorAP/Krill
           path: Krill
+          ref: v0.61.3
 
       - name: Checkout Koral
         uses: actions/checkout@v2
         with:
           repository: KorAP/Koral
           path: Koral
+          ref: v0.41
 
       - name: Set up JDK 17
         uses: actions/setup-java@v1