diff --git a/pyproject.toml b/pyproject.toml
index 1af110d..f5b740d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,7 +35,10 @@ classifiers = [
     "Typing :: Typed",
 ]
 # add your package dependencies here
-dependencies = []
+dependencies = [
+    "gemmi",
+    "pandas",
+]
 
 # https://peps.python.org/pep-0621/#dependencies-optional-dependencies
 # "extras" (e.g. for `pip install .[test]`)