feat: impure symlink

modules/coding/editor/neovim/default.nix

@@ -2,6 +2,7 @@
   config,
   lib,
   pkgs,
+  impure,
   ...
 }:
 let
@@ -14,11 +15,8 @@ in
 
   config = lib.mkIf cfg.enable {
     my.hm = {
-      xdg.configFile."nvim/init.lua".source = ./nvim/init.lua;
-      xdg.configFile."nvim/lua" = {
-        source = ./nvim/lua;
-        recursive = true;
-      };
+      xdg.configFile."nvim/init.lua".source = impure.mkImpureLink ./nvim/init.lua;
+      xdg.configFile."nvim/lua".source = impure.mkImpureLink ./nvim/lua;
       programs.neovim = {
         enable = true;
         defaultEditor = true;

modules/coding/misc.nix

@@ -15,6 +15,7 @@ in
   config = lib.mkIf cfg.enable {
     my.hm = {
       home.packages = with pkgs; [
+        just
         gnumake
         github-cli # gh
       ];

modules/impure.nix

@@ -0,0 +1,26 @@
+{
+  lib,
+  pkgs,
+  self,
+  ...
+}:
+let
+  relativePath =
+    path:
+    assert lib.types.path.check path;
+    lib.strings.removePrefix (toString self) (toString path);
+  mkImpureLink =
+    path:
+    let
+      relative = relativePath path;
+    in
+    pkgs.runCommandLocal relative { } "ln -s ${lib.escapeShellArg (impureRoot + relative)} $out";
+  impureRoot =
+    let
+      impureRoot = builtins.getEnv "IMPURE_ROOT";
+    in
+    if impureRoot == "" then throw "IMPURE_ROOT is not set" else impureRoot;
+in
+{
+  _module.args.impure = { inherit mkImpureLink; };
+}