diff --git a/flake.nix b/flake.nix
index 407018c..c107a57 100644
--- a/flake.nix
+++ b/flake.nix
@@ -15,7 +15,7 @@
             DIR=''${1:-.}
             for f in "$DIR"/*.dfy
             do
-                ${pkgs.dafny}/bin/dafny verify --allow-warnings --verification-time-limit 30 $f || exit 1
+                ${pkgs.dafny}/bin/dafny verify --allow-warnings --verification-time-limit 60 $f || exit 1
             done
           '';