diff --git a/pyproject.toml b/pyproject.toml
index b2019cb..085493d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,6 +19,7 @@ dependencies = [
     "caldav>=1.3",
     "icalendar>=5.0",
     "feedparser>=6.0",
+    "APScheduler>=3.10,<4.0",
     "pywebpush>=2.0",
 ]