added pre-commit support for automated code linting/formatting

.gitignore

@@ -2,4 +2,4 @@
 # Ignore build outputs from performing a nix-build or `nix build` command
 result
 result-*
-
+.pre-commit-config.yaml

flake-module.nix

@@ -1,24 +1,57 @@
-{inputs, ...}:
-{
+{inputs, ...}: {
   # debug = true;
   # We only define machines config in this flake yet, so we only include
   # the module that builds these. This file might get fuller, if we need to
   # build our own packages, that are not flakes.
-  imports = [ ./nixos/flake-module.nix
+  imports = [
+    ./nixos/flake-module.nix
+    inputs.pre-commit-hooks.flakeModule
     # To import a flake module
     # 1. Add foo to inputs
     # 2. Add foo as a parameter to the outputs function
     # 3. Add here: foo.flakeModule
-
   ];
   systems = ["x86_64-linux"];
-#  perSystem = { config, self', inputs', pkgs, system, ... }: {
+  perSystem = {
+    config,
+    inputs',
+    pkgs,
+    ...
+  }: {
+    devShells.default = config.pre-commit.devShell;
+
+    pre-commit = let
+      generatedFiles = [
+        "hardware-configuration\\.nix"
+      ];
+    in {
+      check.enable = true;
+      settings = {
+        # for some reason statix takes it config differently than all the other hooks.
+        settings.statix = {
+          format = "stderr";
+          ignore = generatedFiles;
+        };
+        hooks = {
+          nil.enable = true;
+          statix.enable = true;
+          deadnix = {
+            enable = true;
+            excludes = generatedFiles;
+          };
+          alejandra.enable = true;
+        };
+      };
+    };
+
+    formatter = pkgs.alejandra;
+
     # Per-system attributes can be defined here. The self' and inputs'
     # module parameters provide easy access to attributes of the same
     # system.
+  };
 
   # Equivalent to  inputs'.nixpkgs.legacyPackages.hello;
-#  };
   #      flake = {
   # The usual flake attributes can be defined here, including system-
   # agnostic ones like nixosModule and system-enumerating ones, although

flake.lock

@@ -33,6 +33,24 @@
         "type": "indirect"
       }
     },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1685518550,
+        "narHash": "sha256-o2d0KcvaXzTrPRIo0kOLV0/QXHhDQ5DTi+OxcjO8xqY=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "a1720a10a6cfe8234c0e93907ffe81be440f4cef",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "impermanence": {
       "locked": {
         "lastModified": 1697303681,
@@ -151,12 +169,35 @@
         "type": "github"
       }
     },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-compat": [],
+        "flake-utils": "flake-utils",
+        "gitignore": [],
+        "nixpkgs": [],
+        "nixpkgs-stable": []
+      },
+      "locked": {
+        "lastModified": 1699271226,
+        "narHash": "sha256-8Jt1KW3xTjolD6c6OjJm9USx/jmL+VVmbooADCkdDfU=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "ea758da1a6dcde6dc36db348ed690d09b9864128",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "flake-parts": "flake-parts",
         "impermanence": "impermanence",
         "nixos-mailserver": "nixos-mailserver",
         "nixpkgs": "nixpkgs",
+        "pre-commit-hooks": "pre-commit-hooks",
         "sops-nix": "sops-nix"
       }
     },
@@ -181,6 +222,21 @@
         "type": "github"
       }
     },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
     "utils": {
       "locked": {
         "lastModified": 1605370193,

flake.nix

@@ -17,6 +17,15 @@
     impermanence = {
       url = "github:nix-community/impermanence";
     };
+    pre-commit-hooks = {
+      url = "github:cachix/pre-commit-hooks.nix";
+      inputs = {
+        flake-compat.follows = "";
+        gitignore.follows = "";
+        nixpkgs-stable.follows = "";
+        nixpkgs.follows = "";
+      };
+    };
   };
 
   outputs = inputs@{ flake-parts, ... }: