refactor(flake.nix): Use flake-parts to simplify flake.nix

checks/default.nix

@@ -7,77 +7,76 @@
       pkgs,
       ...
     }:
-    {
-      checks =
-        let
-          mkLint =
-            {
-              name,
-              fileset,
-              checkInputs ? [ ],
-              script,
-            }:
-            pkgs.stdenvNoCC.mkDerivation {
-              inherit name;
-
-              src = lib.fileset.toSource {
-                root = ../.;
-                fileset = lib.fileset.difference fileset (
-                  lib.fileset.fileFilter (
-                    file: file.type != "regular" || file.name == "hardware-configuration.nix"
-                  ) ../.
-                );
-              };
-
-              checkInputs = [ pkgs.nushell ] ++ checkInputs;
-
-              checkPhase = ''
-                nu -c '${script}' | tee $out
-              '';
-
-              dontPatch = true;
-              dontConfigure = true;
-              dontBuild = true;
-              dontInstall = true;
-              dontFixup = true;
-              doCheck = true;
-            };
-        in
+    let
+      mkLint =
         {
-          nix = mkLint {
-            name = "nix-lints";
-            fileset = lib.fileset.fileFilter (file: file.hasExt "nix") ../.;
+          name,
+          fileset,
+          checkInputs ? [ ],
+          script,
+        }:
+        pkgs.stdenvNoCC.mkDerivation {
+          inherit name;
 
-            checkInputs = lib.attrValues {
-              inherit (pkgs) deadnix nixfmt-rfc-style;
-
-              statix = pkgs.statix.overrideAttrs (old: {
-                patches = old.patches ++ [
-                  (pkgs.fetchpatch {
-                    url = "https://github.com/oppiliappan/statix/commit/925dec39bb705acbbe77178b4d658fe1b752abbb.patch";
-                    hash = "sha256-0wacO6wuYJ4ufN9PGucRVJucFdFFNF+NoHYIrLXsCWs=";
-                  })
-                ];
-              });
-            };
-
-            script = /* bash */ ''
-              statix check **/*.nix
-              deadnix --fail **/*.nix
-              nixfmt --check --strict **/*.nix
-            '';
+          src = lib.fileset.toSource {
+            root = ../.;
+            fileset = lib.fileset.difference fileset (
+              lib.fileset.fileFilter (
+                file: file.type != "regular" || file.name == "hardware-configuration.nix"
+              ) ../.
+            );
           };
 
-          lockfile = mkLint {
-            name = "nix-lockfile";
-            fileset = ../flake.lock;
-            checkInputs = lib.attrValues { inherit (inputs'.flint.packages) flint; };
+          checkInputs = [ pkgs.nushell ] ++ checkInputs;
 
-            script = /* bash */ ''
-              flint --fail-if-multiple-versions
-            '';
+          checkPhase = ''
+            nu -c '${script}' | tee $out
+          '';
+
+          dontPatch = true;
+          dontConfigure = true;
+          dontBuild = true;
+          dontInstall = true;
+          dontFixup = true;
+          doCheck = true;
+        };
+    in
+    {
+      checks = {
+        nix = mkLint {
+          name = "nix-lints";
+          fileset = lib.fileset.fileFilter (file: file.hasExt "nix") ../.;
+
+          checkInputs = lib.attrValues {
+            inherit (pkgs) deadnix nixfmt-rfc-style;
+
+            statix = pkgs.statix.overrideAttrs (old: {
+              patches = old.patches ++ [
+                (pkgs.fetchpatch {
+                  url = "https://github.com/oppiliappan/statix/commit/925dec39bb705acbbe77178b4d658fe1b752abbb.patch";
+                  hash = "sha256-0wacO6wuYJ4ufN9PGucRVJucFdFFNF+NoHYIrLXsCWs=";
+                })
+              ];
+            });
           };
-        }
-        // self.nixosConfigurations.hetzner-1.config.serviceTests;
+
+          script = /* bash */ ''
+            statix check **/*.nix
+            deadnix --fail **/*.nix
+            nixfmt --check --strict **/*.nix
+          '';
+        };
+
+        lockfile = mkLint {
+          name = "nix-lockfile";
+          fileset = ../flake.lock;
+          checkInputs = lib.attrValues { inherit (inputs'.flint.packages) flint; };
+
+          script = /* bash */ ''
+            flint --fail-if-multiple-versions
+          '';
+        };
+      }
+      // self.nixosConfigurations.hetzner-1.config.serviceTests;
     };
 }