Running nixpkgs-update (https://github.com/NixOS/infra/blob/main/non-critical-infra/modules/nixpkgs-update/README.md) with UPDATE_INFO: dynamips 0.2.23 -> 0.2.25 https://github.com/GNS3/dynamips/releases
attrpath: dynamips
Checking auto update branch...
[version] 
[version] generic version rewriter does not support multiple hashes
[rustCrateVersion] 
[rustCrateVersion] No cargoHash found
[golangModuleVersion] 
[golangModuleVersion] Not a buildGoModule package with vendorHash
[npmDepsVersion] 
[npmDepsVersion] No npmDepsHash
[updateScript] 
[updateScript] Success
[updateScript] this derivation will be built:
  /nix/store/gzy775d80hsyk1rl3m1yz545k263gmzn-packages.json.drv
building '/nix/store/gzy775d80hsyk1rl3m1yz545k263gmzn-packages.json.drv'...

Going to be running update for following packages:
 - dynamips-0.2.23

Press Enter key to continue...
Running update for:
Enqueuing group of 1 packages
 - dynamips-0.2.23: UPDATING ...
 - dynamips-0.2.23: DONE.

Packages updated!

Diff after rewrites:
diff --git a/pkgs/by-name/dy/dynamips/package.nix b/pkgs/by-name/dy/dynamips/package.nix
index 59d53f71ac96..07461923ea7e 100644
--- a/pkgs/by-name/dy/dynamips/package.nix
+++ b/pkgs/by-name/dy/dynamips/package.nix
@@ -11,13 +11,13 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "dynamips";
-  version = "0.2.23";
+  version = "0.2.25";
 
   src = fetchFromGitHub {
     owner = "GNS3";
     repo = "dynamips";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-+h+WsZ/QrDd+dNrR6CJb2uMG+vbUvK8GTxFJZOxknL0=";
+    hash = "sha256-ms7MtMeGbfPIzhfSgSj7KkTaFhr+fuLz1cOKFHrjchQ=";
   };
 
   patches = [

No auto update branch exists
There might already be an open PR for this update:
- dynamips: 0.2.23 -> 0.2.25
  URL "https://api.github.com/repos/NixOS/nixpkgs/issues/582664"