diff --git a/flake.lock b/flake.lock
index 0f05e93..3a2b94b 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1736241350,
-        "narHash": "sha256-CHd7yhaDigUuJyDeX0SADbTM9FXfiWaeNyY34FL1wQU=",
+        "lastModified": 1746061036,
+        "narHash": "sha256-OxYwCGJf9VJ2KnUO+w/hVJVTjOgscdDg/lPv8Eus07Y=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "8c9fd3e564728e90829ee7dbac6edc972971cd0f",
+        "rev": "3afd19146cac33ed242fc0fc87481c67c758a59e",
         "type": "github"
       },
       "original": {
diff --git a/pkgs/nix-tools/default.nix b/pkgs/nix-tools/default.nix
index a5414cb..7351dda 100644
--- a/pkgs/nix-tools/default.nix
+++ b/pkgs/nix-tools/default.nix
@@ -2,7 +2,7 @@
 , coreutils
 , jq
 , git
-, substituteAll
+, replaceVarsWith
 , stdenv
 , profile ? "/nix/var/nix/profiles/system"
 , # This should be kept in sync with the default
@@ -31,40 +31,53 @@
 
 let
   extraPath = lib.makeBinPath [ coreutils jq git nixPackage ];
-
-  writeProgram = name: env: src:
-    substituteAll ({
-      inherit name src;
-      dir = "bin";
-      isExecutable = true;
-      meta.mainProgram = name;
-    } // env);
+  
+  writeProgram =
+    attrs:
+    replaceVarsWith (
+      attrs
+      // {
+        dir = "bin";
+        isExecutable = true;
+        meta.mainProgram = attrs.name;
+      }
+    );
 
   path = "${extraPath}:${systemPath}";
 in
 {
-  darwin-option = writeProgram "darwin-option"
-    {
+  darwin-option = writeProgram {
+    name = "darwin-option";
+    src = ./darwin-option.sh;
+
+    replacements = {
       inherit path nixPath;
       inherit (stdenv) shell;
-    }
-    ./darwin-option.sh;
+    };
+  };
 
-  darwin-rebuild = writeProgram "darwin-rebuild"
-    {
+  darwin-rebuild = writeProgram {
+    name = "darwin-rebuild";
+    src = ./darwin-rebuild.sh;
+
+    replacements = {
       inherit path nixPath profile;
       inherit (stdenv) shell;
-      postInstall = ''
-        mkdir -p $out/share/zsh/site-functions
-        cp ${./darwin-rebuild.zsh-completions} $out/share/zsh/site-functions/_darwin-rebuild
-      '';
-    }
-    ./darwin-rebuild.sh;
+    };
 
-  darwin-version = writeProgram "darwin-version"
-    {
+    postInstall = ''
+      mkdir -p $out/share/zsh/site-functions
+      cp ${./darwin-rebuild.zsh-completions} $out/share/zsh/site-functions/_darwin-rebuild
+    '';
+  };
+
+  darwin-version = writeProgram {
+    name = "darwin-version";
+    src = ./darwin-version.sh;
+
+    replacements = {
       inherit (stdenv) shell;
       path = lib.makeBinPath [ jq ];
-    }
-    ./darwin-version.sh;
+    };
+  };
 }