diff --git a/pyproject.toml b/pyproject.toml
index 77446213..4c8ade98 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -204,6 +204,8 @@ optional-dependencies.test = [
   "adbcbridge>=0.1.3,<0.2",
   "apprise>=2,<3",
   "boto3<2",
+  # ConnectorX publishes no sdist and no wheel for Python 3.15 yet.
+  "connectorx<0.5; python_version<'3.15'",
   "pendulum[test]>=3,<4",
   "pyexcel-ods3<0.7",
   "pytest<10",