1{...}: {
 2  programs.helix.languages = {
 3    language = [
 4      {
 5        name = "nix";
 6        auto-format = true;
 7        indent = {
 8          tab-width = 2;
 9          unit = "  ";
10        };
11        language-servers = ["nixd"];
12      }
13    ];
14    language-server = {
15      nil.config.nil = {
16        formatting.command = ["alejandra"];
17        nix = {
18          maxMemoryMB = 4096;
19          flake = {
20            autoArchive = false;
21            autoEvalInputs = true;
22          };
23        };
24      };
25      nixd.config.nixd = {
26        formatting.command = ["alejandra"];
27      };
28    };
29  };
30}