Running nixpkgs-update (https://nix-community.org/update-bot/) with UPDATE_INFO: ferron 0 -> 1
attrpath: ferron
Checking auto update branch...
[version] 
[version] generic version rewriter does not support multiple hashes
[rustCrateVersion] 
[rustCrateVersion] skipping because derivation has updateScript
[golangModuleVersion] 
[golangModuleVersion] Not a buildGoModule package with vendorHash
[npmDepsVersion] 
[npmDepsVersion] No npmDepsHash
[updateScript] 
[updateScript] Success
[updateScript] this derivation will be built:
  /nix/store/y0kp0shal2l0drl1qnb1dcp56sj52y6q-packages.json.drv
building '/nix/store/y0kp0shal2l0drl1qnb1dcp56sj52y6q-packages.json.drv'...

Going to be running update for following packages:
 - ferron-2.2.1

Press Enter key to continue...
Running update for:
Enqueuing group of 1 packages
 - ferron-2.2.1: UPDATING ...
 - ferron-2.2.1: DONE.

Packages updated!

Diff after rewrites:
diff --git a/pkgs/by-name/fe/ferron/package.nix b/pkgs/by-name/fe/ferron/package.nix
index 9d70a767381c..39308debedea 100644
--- a/pkgs/by-name/fe/ferron/package.nix
+++ b/pkgs/by-name/fe/ferron/package.nix
@@ -10,13 +10,13 @@
 
 rustPlatform.buildRustPackage (finalAttrs: {
   pname = "ferron";
-  version = "2.2.1";
+  version = "1.3.7";
 
   src = fetchFromGitHub {
     owner = "ferronweb";
     repo = "ferron";
     tag = finalAttrs.version;
-    hash = "sha256-+Esbsr+pqRSRd3M7mFhNl+KVcz3wO5YlZrna8mYsV80=";
+    hash = "sha256-HpFE+GrI/YJOErMPmM5zJJBjMA8w84eWYk32/NjBWMc=";
   };
 
   # ../../ is cargoDepsCopy, and obviously does not contain monoio's README.md
@@ -25,7 +25,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
       --replace-fail '#![doc = include_str!("../../README.md")]' ""
   '';
 
-  cargoHash = "sha256-/F1CqzOKscT/rOsJaY+PwZPMBDxSEoI+zN/GsH5P37k=";
+  cargoHash = "sha256-9vNzCH0mvMry34ILKsaFw7nqpL37ZKPAbDIDgbW/MZY=";
 
   nativeBuildInputs = [
     pkg-config

No auto update branch exists
Received ExitFailure 1 when running
Raw command: nix-build --option sandbox true --arg config "{ allowUnfree = true; allowAliases = false; }" --arg overlays "[ ]" -A ferron
nix build failed.
got build log for 'ferron' from 'daemon'
Using versionCheckHook
Running phase: unpackPhase
@nix { "action": "setPhase", "phase": "unpackPhase" }
unpacking source archive /nix/store/9yygca3bagzf8bv4lk5v2q9n29q6fza4-source
source root is source
Executing cargoSetupPostUnpackHook
Finished cargoSetupPostUnpackHook
Running phase: patchPhase
@nix { "action": "setPhase", "phase": "patchPhase" }
substitute(): ERROR: file '/build/ferron-1.3.7-vendor/monoio-0.2.4/src/lib.rs' does not exist