diff --git a/pyproject.toml b/pyproject.toml
index 9ffdd641..d742f6bb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,6 +26,7 @@ dependencies = [
   "category-encoders>=1.2.8",
   "black==23.3.0",
   "psutil",
+  "ConfigSpace>=0.7.1",
 ]
 
 [project.optional-dependencies]