diff --git a/pkgs/development/python-modules/mitogen/default.nix b/pkgs/development/python-modules/mitogen/default.nix
index 32241e11b9bd..cc88e3f3a3e5 100644
--- a/pkgs/development/python-modules/mitogen/default.nix
+++ b/pkgs/development/python-modules/mitogen/default.nix
@@ -7,14 +7,14 @@
 
 buildPythonPackage (finalAttrs: {
   pname = "mitogen";
-  version = "0.3.39";
+  version = "0.3.40";
   pyproject = true;
 
   src = fetchFromGitHub {
     owner = "mitogen-hq";
     repo = "mitogen";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-VX8BvHTL3Ke6T+iGc4YGery5uXf/JvE7h5dnyK4/ESY=";
+    hash = "sha256-yGIXgqngr4hjejCuYaNTArncbs0Pcg1Iia5geujPQhg=";
   };
 
   build-system = [ setuptools ];