diff --git a/pkgs/tools/networking/cassowary/default.nix b/pkgs/tools/networking/cassowary/default.nix
index 7d9a07badbb..b918516f926 100644
--- a/pkgs/tools/networking/cassowary/default.nix
+++ b/pkgs/tools/networking/cassowary/default.nix
@@ -2,13 +2,13 @@
 
 buildGoModule rec {
   pname = "cassowary";
-  version = "0.12.0";
+  version = "0.12.1";
 
   src = fetchFromGitHub {
     owner = "rogerwelin";
     repo = pname;
     rev = "v${version}";
-    sha256 = "sha256-HRshuMnRPMzatOYYI//yEtjC46kORGXaAWJJjLHW2+k=";
+    sha256 = "sha256-1so9EMry7U6GfpxgqLpcqC+ZaWAn4qAsnyDZvo0FAZY=";
   };
 
   vendorSha256 = "sha256-d8JPsHBGkZ/MeoHTCLxi6JeNomER/0veWjqmqGal8eE=";