Fix legacy nix shell

flake.lock

@@ -21,6 +21,22 @@
         "type": "github"
       }
     },
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1650374568,
+        "narHash": "sha256-Z+s0J8/r907g149rllvwhb4pKi8Wam5ij0st8PwAh+E=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "b4a34015c698c7793d592d66adbab377907a2be8",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-utils": {
       "locked": {
         "lastModified": 1667395993,
@@ -182,6 +198,7 @@
     "root": {
       "inputs": {
         "darwin": "darwin",
+        "flake-compat": "flake-compat",
         "flake-utils": "flake-utils",
         "home-manager": "home-manager",
         "nil": "nil",

flake.nix

@@ -1,8 +1,8 @@
 {
   description = "NixOS configuration with flakes";
-  outputs = { self, flake-utils, home-manager, nixpkgs-nixos-unstable
+  outputs = { self, flake-utils, flake-compat, home-manager
-    , nixpkgs-master, nixpkgs-stable, darwin, nixos-hardware, nur, sops, nil
+    , nixpkgs-nixos-unstable, nixpkgs-master, nixpkgs-stable, darwin
-    }@inputs:
+    , nixos-hardware, nur, sops, nil }@inputs:
 
     let
       mkServer = pkgs: system: hostname:
@@ -254,6 +254,10 @@
       inputs.nixpkgs.follows = "nixpkgs-stable";
     };
 
+    flake-compat = {
+      url = "github:edolstra/flake-compat";
+      flake = false;
+    };
   };
 
 }