significantly improve purity

tests/basic/configuration.nix

@@ -1,22 +1,18 @@
 { pkgs, lib, config, modulesPath, ... }:
 let
   name = config.networking.hostName;
-  nixosLibPath = (modulesPath + "/../lib");
   moduleList = import (modulesPath + "/module-list.nix");
 
-  optionalPath = p: lib.optional (builtins.pathExists p) p;
+  dynixFromSearchPath = let
+    res = builtins.tryEval <dynix>;
+  in lib.optional res.success res.value;
 in
-assert builtins.pathExists nixosLibPath;
-builtins.seq lib
-builtins.seq modulesPath
-builtins.seq moduleList
 {
   imports = moduleList ++ [
-    (modulesPath + "/testing/test-instrumentation.nix")
+    "${modulesPath}/testing/test-instrumentation.nix"
+    ./hardware-configuration.nix
   ] ++ lib.concatLists [
-    (optionalPath ./hardware-configuration.nix)
-    (optionalPath ./dynamicism)
-    (optionalPath ../../modules/dynamicism)
+    dynixFromSearchPath
   ];
 
   system.switch.enable = true;
@@ -32,13 +28,18 @@ builtins.seq moduleList
 
   nix = {
     package = pkgs.lixPackageSets.latest.lix;
-    nixPath = [ "nixpkgs=${pkgs.path}" ];
+    nixPath = [
+      "nixpkgs=${pkgs.path}"
+      "/nix/var/nix/profiles/per-user/root/profile/share/nixos/modules"
+    ];
 
     settings = {
       experimental-features = [ "nix-command" "pipe-operator" ];
       substituters = lib.mkForce [ ];
       hashed-mirrors = null;
       connect-timeout = 1;
+      # For my debugging purposes.
+      show-trace = true;
     };
   };
 
@@ -54,6 +55,7 @@ builtins.seq moduleList
   dynamicism.for.gotosocial.enable = true;
 
   environment.pathsToLink = [ "/share" ];
+  environment.extraOutputsToInstall = [ "modules" ];
   environment.variables = {
     "NIXOS_CONFIG" = "/etc/nixos/configuration.nix";
   };