Tree! It's the square hole for imports. That's right. It goes in the

square hole.

config/hosts/settings.nix

@@ -1,5 +0,0 @@
-{ ... }: {
-  excludes = [
-    "to-do"
-  ];
-}

config/modules/home/settings.nix

@@ -1,12 +0,0 @@
-{ sources, ... }: {
-  functor = {
-    enable = true;
-    external = [
-      (import (sources.arcexprs + "/modules")).home-manager
-      (import (sources.katexprs + "/modules")).home
-      (import (sources.impermanence + "/home-manager.nix"))
-      (import sources.anicca).modules.home
-      (sources.tf-nix + "/modules/home/secrets.nix")
-    ];
-  };
-}

config/modules/meta/settings.nix

@@ -1,5 +0,0 @@
-{ sources, ... }: {
-  functor = {
-    enable = true;
-  };
-}

config/modules/nixos/settings.nix

@@ -1,13 +0,0 @@
-{ sources, ... }: {
-  functor = {
-    enable = true;
-    external = [
-      (import (sources.arcexprs + "/modules")).nixos
-      (import (sources.katexprs + "/modules")).nixos
-      (import (sources.impermanence + "/nixos.nix"))
-      (import sources.anicca).modules.nixos
-      (sources.tf-nix + "/modules/nixos/secrets.nix")
-      (sources.tf-nix + "/modules/nixos/secrets-users.nix")
-    ];
-  };
-}

config/profiles/cross/default.nix

@@ -1,5 +1,5 @@
 { lib, tree, ... }: with lib; let
-  profiles = tree.dirs // tree.files;
+  profiles = tree.prev;
   appendedProfiles = with profiles; {
     aarch64 = {
       deploy.profile.cross = {

config/profiles/cross/settings.nix

@@ -1,4 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders.default.enable = true;
-}

config/profiles/default.nix

@@ -1,11 +0,0 @@
-{ lib, tree, ... }@args: with lib;
-let
-  wrappedBase = base: mapAttrs
-    (name: paths: {
-      imports = if isAttrs paths then attrValues paths else singleton paths;
-    })
-    (base);
-in
-(wrappedBase (filterAttrs (n: v: ! v ? "default") tree.dirs))
-// (mapAttrs (n: v: removeAttrs v [ "default" ]) (filterAttrs (n: v: v ? "default") tree.dirs))
-  // (removeAttrs tree.files [ "default" ])

config/profiles/hardware/default.nix

@@ -1,8 +1,5 @@
 { lib, tree, ... }: with lib; let
-  profiles = (filterAttrs (n: v: v ? "default") tree.dirs)
-    // tree.defaultDirs
-    // (mapAttrs (n: v: removeAttrs v [ "default" ]) (filterAttrs (n: v: v ? "default") tree.dirs))
-    // tree.files;
+  profiles = tree.prev;
   appendedProfiles = with profiles; {
     ms-7b86 = {
       imports = [

config/profiles/hardware/laptop/settings.nix

@@ -1,7 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders = {
-    enable = true;
-    default.enable = true;
-  };
-}

config/profiles/hardware/oracle/default.nix

@@ -1,5 +1,5 @@
 { lib, sources, tree, ... }: with lib; let
-  profiles = tree.dirs // tree.files;
+  profiles = tree.prev;
   appendedProfiles = with profiles; {
     ubuntu = { config, ... }: {
       deploy.profile.hardware.oracle = {

config/profiles/hardware/oracle/settings.nix

@@ -1,4 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders.default.enable = true;
-}

config/profiles/hardware/settings.nix

@@ -1,5 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders.enable = true;
-  includeFolders.default.enable = true;
-}

config/profiles/settings.nix

@@ -1,5 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  recursiveInclude = true;
-  includeFolders.default.enable = true;
-}

config/services/settings.nix

@@ -1,6 +0,0 @@
-{ ... }: {
-  includeFolders = {
-    enable = true;
-    default.enable = true;
-  };
-}

config/users/arc/settings.nix

@@ -1,7 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders = {
-    enable = true;
-    default.enable = true;
-  };
-}

config/users/hexchen/settings.nix

@@ -1,7 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  includeFolders = {
-    enable = true;
-    default.enable = true;
-  };
-}

config/users/kat/base/vim/default.nix

@@ -1,6 +0,0 @@
-{ ... }: {
-  imports = [
-    ./vim.nix
-    ./nvim.nix
-  ];
-}

config/users/kat/default.nix

@@ -1,19 +1,19 @@
 { lib, tree, ... }: with lib; let
   wrapImports = imports: mapAttrs
-    (name: paths: { config, ... }: {
+    (_: paths: { config, ... }: {
       config.home-manager.users.kat = {
-        imports = if isAttrs paths then attrValues paths else singleton paths;
+        imports = singleton paths;
       };
     })
     imports;
-  dirImports = wrapImports tree.dirs;
-  serviceImports = wrapImports tree.dirs.services;
+  dirImports = wrapImports tree.prev;
+  serviceImports = wrapImports tree.prev.services;
 in
-(removeAttrs dirImports (singleton "base")) // {
+dirImports // {
   base = {
     imports = [
       dirImports.base
-      tree.files.nixos
+      tree.prev.nixos
     ];
   };
   server = { };

config/users/kat/dev/settings.nix

@@ -1,4 +0,0 @@
-{ ... }: {
-  excludes = [
-  ];
-}

config/users/kat/settings.nix

@@ -1,7 +0,0 @@
-{ ... }: {
-  defaultOnly = true;
-  recursiveInclude = true;
-  includeFolders = {
-    default.enable = true;
-  };
-}

default.nix

@@ -23,11 +23,55 @@ let
     allStr = toString all;
   };
 
+  tree = import ./tree.nix { inherit lib; } {
+    inherit sources;
+    folder = ./config;
+    config = {
+      "modules/nixos" = {
+        functor = {
+          enable = true;
+          external = [
+            (import (sources.arcexprs + "/modules")).nixos
+            (import (sources.katexprs + "/modules")).nixos
+            (import (sources.impermanence + "/nixos.nix"))
+            (import sources.anicca).modules.nixos
+            (sources.tf-nix + "/modules/nixos/secrets.nix")
+            (sources.tf-nix + "/modules/nixos/secrets-users.nix")
+          ];
+        };
+      };
+      "modules/home" = {
+        functor = {
+          enable = true;
+          external = [
+            (import (sources.arcexprs + "/modules")).home-manager
+            (import (sources.katexprs + "/modules")).home
+            (import (sources.impermanence + "/home-manager.nix"))
+            (import sources.anicca).modules.home
+            (sources.tf-nix + "/modules/home/secrets.nix")
+          ];
+        };
+      };
+      "modules/meta".functor.enable = true;
+      "profiles/*".functor.enable = true;
+      "profiles/hardware".evaluateDefault = true;
+      "profiles/cross".evaluateDefault = true;
+      "profiles/hardware/*".evaluateDefault = true;
+      "services/*".aliasDefault = true;
+      "trusted/secrets".evaluateDefault = true;
+      "trusted".excludes = [ "tf" ];
+      "users/*".evaluateDefault = true;
+      "users/kat/*".functor.enable = true;
+      "users/kat/services/mpd".functor.enable = true;
+    };
+  };
+
   root = ./.;
-  xarg = lib.recursiveMod { folder = ./config; inherit sources lib; };
 
   metaBase = import ./meta.nix { inherit config lib pkgs root; };
 
+  xarg = tree.impure;
+
   eval = lib.evalModules {
     modules = lib.singleton metaBase
       ++ lib.singleton xarg.modules.meta
@@ -44,13 +88,14 @@ let
       (lib.attrNames xarg.hosts));
 
     specialArgs = {
-      inherit sources root;
+      inherit sources root tree;
       meta = self;
     } // xarg;
   };
 
   inherit (eval) config;
 
-  self = config // { inherit pkgs lib sourceCache sources; } // xarg;
+
+  self = config // { inherit pkgs lib sourceCache sources tree; } // xarg;
 in
 self

tree.nix

@@ -0,0 +1,121 @@
+{ lib }: { config, folder, sources, ... }@args: with lib; let
+  pureTreeGrab = { base, path }: let
+    realPath = toString path;
+    dirContents = builtins.readDir path;
+    isDirectory = entry: dirContents."${entry}" == "directory";
+    isHidden = entry: hasPrefix "." entry;
+    isDir = entry: _: (isDirectory entry) && !(isHidden entry);
+    directories = filterAttrs isDir dirContents;
+    isNixFile = entry: _: let
+      result = builtins.match "(.*)\\.nix" entry;
+    in result != null && builtins.length result > 0;
+    nixFiles = filterAttrs isNixFile dirContents;
+    getPath = entry: "${realPath}/${entry}";
+    getPaths = entries: mapAttrs' (n: v:
+      nameValuePair (removeSuffix ".nix" n) (getPath n)
+    ) entries;
+    nixFilePaths = getPaths nixFiles;
+    dirPaths = getPaths directories;
+    recursedPaths = mapAttrs (_: fullPath: pureTreeGrab {
+      inherit base;
+      path = fullPath;
+    }) dirPaths;
+    contents = recursedPaths // nixFilePaths;
+ in contents;
+  configTreeStruct = { config, ... }: {
+    options.treeConfig = mkOption {
+      type = with types; attrsOf (submodule ({ name, options, config, ... }: {
+        options = {
+          evaluateDefault = mkOption {
+            type = types.bool;
+            description = "Replace the contents of this branch or leaf with those provided by the evaluation of default.nix.";
+            default = false;
+          };
+          aliasDefault = mkOption {
+            type = types.bool;
+            description = "Replace the contents of this branch or leaf with the default.nix.";
+            default = false;
+          };
+          excludes = mkOption {
+            type = types.listOf types.str;
+            description = "Exclude files or folders from the recurser.";
+            default = [];
+          };
+          functor = {
+            enable = mkOption {
+              type = types.bool;
+              description = "Provide a functor for the path provided";
+              default = false;
+            };
+            external = mkOption {
+              type = types.listOf types.unspecified;
+              description = "Add external imports into the functor.";
+              default = [];
+            };
+            excludes = mkOption {
+              type = types.listOf types.str;
+              description = "Exclude files or folders from the functor.";
+              default = [];
+            };
+          };
+        };
+      }));
+    };
+    config.treeConfig = {
+      "*" = {};
+    };
+  };
+  configTree.treeConfig = config;
+  configTreeModule = (evalModules {
+    modules = [
+      configTreeStruct
+      configTree
+    ];
+  }).config.treeConfig;
+  mapAttrsRecursive = f: set: let
+    recurse = path: set: let
+      g = name: value: if isAttrs value
+        then f (path ++ [name]) (recurse (path ++ [name]) value)
+        else f (path ++ [name]) value;
+    in mapAttrs g set;
+  in recurse [] set;
+  getPathString = path: concatStringsSep "/" path;
+  getConfig = path: default: configTreeModule.${getPathString path} or default;
+  revtail = path: sublist 0 (length path - 1) path;
+  getConfigRecursive = path: let
+    parentPath = revtail path;
+  in getConfig (path ++ singleton "*") (getConfigRecursive parentPath);
+  processLeaves = tree: config: mapAttrsRecursive (path: value: let
+    pathString = getPathString path;
+    leafConfig = getConfig path (getConfigRecursive (revtail path));
+    processConfig = path: value: let
+      processFunctor = prev: prev // {
+        __functor = self: { ... }: {
+          imports = attrValues (removeAttrs prev leafConfig.functor.excludes) ++ leafConfig.functor.external;
+        };
+      };
+      processAliasDefault = prev: prev.default;
+      processDefault = prev: import prev.default (args // {
+        inherit lib;
+        tree = {
+          prev = removeAttrs prev (singleton "default");
+          pure = pureTree;
+          impure = impureTree;
+        };
+      });
+      processExcludes = prev: removeAttrs prev leafConfig.excludes;
+      processes = optionals (isAttrs value) (
+        optional (leafConfig.excludes != []) processExcludes
+        ++ optional leafConfig.evaluateDefault processDefault
+        ++ optional leafConfig.aliasDefault processAliasDefault
+        ++ optional leafConfig.functor.enable processFunctor
+      );
+    in pipe value processes;
+  in processConfig path value) tree;
+  pureTree = pureTreeGrab { base = folder; path = folder; };
+  impureTree = processLeaves pureTree configTreeModule;
+in {
+  config = configTreeModule;
+  pure = pureTree;
+  impure = impureTree;
+}