diff --git a/.gitea/workflows/test.yml b/.gitea/workflows/test.yml
index c295b24..e203eec 100644
--- a/.gitea/workflows/test.yml
+++ b/.gitea/workflows/test.yml
@@ -82,8 +82,7 @@ jobs:
           progress: false
       - name: Run testnet stack
         working-directory: ./plugeth-statediff
-        run: |
-          ./scripts/run-test-stack.sh ../fixturenet-eth-stacks/stack-orchestrator/stacks/fixturenet-plugeth
+        run: ./scripts/run-test-stack.sh
       - name: Run tests
         working-directory: ./system-tests
         run: |
diff --git a/scripts/run-test-stack.sh b/scripts/run-test-stack.sh
index f67ef16..a5668dc 100755
--- a/scripts/run-test-stack.sh
+++ b/scripts/run-test-stack.sh
@@ -9,7 +9,7 @@ CONFIG_DIR=$(readlink -f "${CONFIG_DIR:-$(mktemp -d)}")
 export CERC_REPO_BASE_DIR="${CERC_REPO_BASE_DIR:-$(git rev-parse --show-toplevel)/..}"
 
 # Note: stack path should be absolute, otherwise SO looks for it in packaged stacks
-stack_dir=$(readlink -f "$1")
+stack_dir=$(readlink -f "${1:-../fixturenet-eth-stacks/stack-orchestrator/stacks/fixturenet-plugeth}")
 
 laconic_so="laconic-so --verbose --stack $stack_dir"