Add devenv nix

systems/gandalf/hardware-configuration.nix

@@ -1,12 +1,11 @@
 # Do not modify this file!  It was generated by ‘nixos-generate-config’
 # and may be overwritten by future invocations.  Please make changes
 # to /etc/nixos/configuration.nix instead.
-{
-  config,
-  lib,
-  pkgs,
-  modulesPath,
-  ...
+{ config
+, lib
+, pkgs
+, modulesPath
+, ...
 }:
 
 {

systems/gandalf/mtp-fix.nix

@@ -4,27 +4,27 @@
   nixpkgs.overlays = [
     (
       final: prev:
-      let
-        targetVersion = "1.1.23";
-      in
-      {
-        libmtp =
-          if builtins.compareVersions prev.libmtp.version targetVersion >= 0 then
-            prev.libmtp
-          else
-            prev.libmtp.overrideAttrs (_: {
-              version = targetVersion;
+        let
+          targetVersion = "1.1.23";
+        in
+        {
+          libmtp =
+            if builtins.compareVersions prev.libmtp.version targetVersion >= 0 then
+              prev.libmtp
+            else
+              prev.libmtp.overrideAttrs (_: {
+                version = targetVersion;
 
-              src = final.fetchFromGitHub {
-                owner = "libmtp";
-                repo = "libmtp";
-                rev = "v${targetVersion}";
-                hash = "sha256-FlPj9PEeOAWabU11dFTzDgY9TBbgmJclbeL0iULYw6A=";
-              };
+                src = final.fetchFromGitHub {
+                  owner = "libmtp";
+                  repo = "libmtp";
+                  rev = "v${targetVersion}";
+                  hash = "sha256-FlPj9PEeOAWabU11dFTzDgY9TBbgmJclbeL0iULYw6A=";
+                };
 
-              patches = [ ];
-            });
-      }
+                patches = [ ];
+              });
+        }
     )
   ];
 }