home: git: switch to 'delta'

Now that my issue with it has been resolved [1], let's switch to the
more mature tool.

This also solves a small issue that I had with `diff-highlight` which is
that non-highlighted text should not be boldened.

[1]: https://github.com/dandavison/delta/issues/544

flake.lock

@@ -7,16 +7,16 @@
         ]
       },
       "locked": {
-        "lastModified": 1634404028,
-        "narHash": "sha256-JyP2Y6JCCYvUcVz7CXX5pXUfTGTU4GX51Yza82BgMfk=",
+        "lastModified": 1637625975,
+        "narHash": "sha256-ByDgmhpLykhAVeaFggjqoSRdl2OzTDODnxjPuu97fL4=",
         "owner": "ryantm",
         "repo": "agenix",
-        "rev": "53aa91b4170da35a96fab1577c9a34bc0da44e27",
+        "rev": "a0e9ca505c82e762d39e9477a428b537a0aab022",
         "type": "github"
       },
       "original": {
         "owner": "ryantm",
-        "ref": "master",
+        "ref": "main",
         "repo": "agenix",
         "type": "github"
       }

flake.nix

@@ -5,7 +5,7 @@
       type = "github";
       owner = "ryantm";
       repo = "agenix";
-      ref = "master";
+      ref = "main";
       inputs = {
         nixpkgs.follows = "nixpkgs";
       };

home/git/default.nix

@@ -39,6 +39,33 @@ in
 
     lfs.enable = true;
 
+    delta = {
+      enable = true;
+
+      options = {
+        features = "diff-highlight decorations";
+
+        # Less jarring style for `diff-highlight` emulation
+        diff-highlight = {
+          minus-style = "red";
+          minus-non-emph-style = "red";
+          minus-emph-style = "bold red 52";
+
+          plus-style = "green";
+          plus-non-emph-style = "green";
+          plus-emph-style = "bold green 22";
+
+          whitespace-error-style = "reverse red";
+        };
+
+        # Personal preference for easier reading
+        decorations = {
+          keep-plus-minus-markers = true;
+          paging = "always";
+        };
+      };
+    };
+
     # There's more
     extraConfig = {
       # Makes it a bit more readable
@@ -72,13 +99,6 @@ in
         whitespace = "red reverse";
       };
 
-      "color.diff-highlight" = {
-        oldNormal = "red bold";
-        oldHighlight = "red bold 52";
-        newNormal = "green bold";
-        newHighlight = "green bold 22";
-      };
-
       commit = {
         # Show my changes when writing the message
         verbose = true;
@@ -99,16 +119,6 @@ in
         defaultBranch = "main";
       };
 
-      pager =
-        let
-          diff-highlight = "${pkgs.gitAndTools.gitFull}/share/git/contrib/diff-highlight/diff-highlight";
-        in
-        {
-          diff = "${diff-highlight} | less";
-          log = "${diff-highlight} | less";
-          show = "${diff-highlight} | less";
-        };
-
       pull = {
         # Avoid useless merge commits
         rebase = true;

modules/system/nix/default.nix

@@ -18,9 +18,6 @@ in
         extraOptions = ''
           experimental-features = nix-command flakes
         '';
-
-        # Keep my system responsive during builds
-        daemonNiceLevel = 19;
       };
     }