diff --git a/src/ifcpatch/pyproject.toml b/src/ifcpatch/pyproject.toml
index 8329ba63d0..5d43201a25 100644
--- a/src/ifcpatch/pyproject.toml
+++ b/src/ifcpatch/pyproject.toml
@@ -17,6 +17,12 @@ classifiers = [
 ]
 dependencies = ["ifcopenshell", "toposort", "numpy"]
 
+[project.optional-dependencies]
+advanced = [
+  "sqlite3",
+  "mysql-connector-python",
+]
+
 [project.urls]
 Homepage = "http://ifcopenshell.org"
 Documentation = "https://docs.ifcopenshell.org"