diff --git a/.github/unittest/install_dependencies_nightly.sh b/.github/unittest/install_dependencies_nightly.sh
index a00b1d4..b337e1d 100644
--- a/.github/unittest/install_dependencies_nightly.sh
+++ b/.github/unittest/install_dependencies_nightly.sh
@@ -1,10 +1,13 @@
 python -m pip install --upgrade pip
 python -m pip install flake8 pytest pytest-cov hydra-core tqdm
 
-# Not using nightly torch, MolScore, promptsmiles
-python -m pip install torch torchvision MolScore promptsmiles
+# Not using nightly torch
+python -m pip install torch torchvision
 # python -m pip install --pre torch --extra-index-url https://download.pytorch.org/whl/nightly/cpu --force-reinstall
 
+# Not testing these dependencies for now
+# python -m pip MolScore promptsmiles
+
 cd ../acegen-open
 pip install -e .
 pip uninstall --yes torchrl
diff --git a/tests/test_mamba_model.py b/tests/test_mamba_model.py
index 807937d..98598ee 100644
--- a/tests/test_mamba_model.py
+++ b/tests/test_mamba_model.py
@@ -8,6 +8,19 @@
 )
 from utils import get_default_devices
 
+try:
+    from mamba_ssm.models.mixer_seq_simple import MixerModel
+
+    mamba_available = True
+except ImportError as err:
+    mamba_available = False
+
+
+skip_if_mamba_not_available = pytest.mark.skipif(
+    not mamba_available,
+    reason="mamba-ssm library is not available, skipping this test",
+)
+
 
 def generate_valid_data_batch(
     vocabulary_size: int, batch_size: int, sequence_length: int
@@ -21,6 +34,7 @@ def generate_valid_data_batch(
     return batch
 
 
+@skip_if_mamba_not_available
 @pytest.mark.parametrize("vocabulary_size", [10])
 @pytest.mark.parametrize("device", get_default_devices())
 def test_mamba_actor(vocabulary_size, device, sequence_length=5, batch_size=10):
@@ -52,6 +66,7 @@ def test_mamba_actor(vocabulary_size, device, sequence_length=5, batch_size=10):
     assert "action" in training_batch.keys()
 
 
+@skip_if_mamba_not_available
 @pytest.mark.parametrize("vocabulary_size", [10])
 @pytest.mark.parametrize("device", get_default_devices())
 @pytest.mark.parametrize("critic_value_per_action", [True, False])
@@ -95,6 +110,7 @@ def test_mamba_critic(
         assert "state_value" in training_batch.keys()
 
 
+@skip_if_mamba_not_available
 @pytest.mark.parametrize("vocabulary_size", [10])
 @pytest.mark.parametrize("device", get_default_devices())
 @pytest.mark.parametrize("critic_value_per_action", [True, False])