diff --git a/setup.py b/setup.py
index 474d02e8..595b401b 100644
--- a/setup.py
+++ b/setup.py
@@ -33,6 +33,7 @@
         "tiktoken",
         "rdkit",
         "streamlit",
+        "mdtraj",
     ],
     test_suite="tests",
     long_description=long_description,