diff --git a/nitric/application.py b/nitric/application.py
index ba56dc9..5c883b6 100644
--- a/nitric/application.py
+++ b/nitric/application.py
@@ -88,7 +88,7 @@ def _create_tracer(cls, local: bool = True, sampler: int = 100) -> TracerProvide
         return provider
 
     @classmethod
-    def run(cls):
+    def run(cls) -> None:
         """
         Start the nitric application.