diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f15b634502fef608302d7b32b4edfacac058acd1..d63b2caa56ca46160aaf755b7037bb70d7e2facb 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,6 +1,7 @@
 run_tests:
   image: "python:$VERSION"
   script:
+    - apt update && apt install -y graphviz
     - pip install -e .[dev]
     - export PYTHONPATH="$(pwd)"
     - coverage run --source . run_tests.py
diff --git a/tests/test_cli.py b/tests/test_cli.py
index fab491414d834305052fd08aa103e34ec896991f..981deae94728cb080034e0b42dee5576b09a6505 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -7,8 +7,8 @@ from bioflow_insight_cli.main import cli
 
 class TestCall(unittest.TestCase):
     def test_cli_works(self):
-        #cli("./wf_test/main.nf", render_graphs=False)
         cli("./wf_test/main.nf", render_graphs=False)
+        cli("./wf_test/main.nf", render_graphs=True)
 
     def test_cli_output_considered(self):
         with TemporaryDirectory() as my_temp_dir: