modules/shared/nix-daemon: disable channels and set flake registry, n…

…ix path

modules/shared/nix-daemon.nix

@@ -1,7 +1,28 @@
-{ pkgs, ... }:
+{
+  config,
+  inputs,
+  pkgs,
+  ...
+}:
 
 let
   asGB = size: toString (size * 1024 * 1024 * 1024);
+
+  # srvos
+  flake-registry = pkgs.writers.writeJSON "flake-registry.json" {
+    version = 2;
+    flakes = pkgs.lib.mapAttrsToList (name: value: {
+      exact = true;
+      from = {
+        id = name;
+        type = "indirect";
+      };
+      to = {
+        path = toString value;
+        type = "path";
+      };
+    }) ({ inherit (inputs) self; } // inputs.self.inputs);
+  };
 in
 {
   nix = {
@@ -15,9 +36,16 @@ in
     settings.min-free = asGB 1;
     settings.max-free = asGB 50;
 
-    # useful for ad-hoc nix-shell's for debugging
-    # use mkForce to avoid search path warnings with nix-darwin
-    nixPath = pkgs.lib.mkForce [ "nixpkgs=${pkgs.path}" ];
+    channel.enable = false;
+    # disable system registry
+    registry = pkgs.lib.mkForce { };
+    settings = {
+      # set global registry
+      inherit flake-registry;
+    };
+    # explicitly set nix-path, NIX_PATH to nixpkgs from global registry
+    settings.nix-path = [ "nixpkgs=flake:nixpkgs" ];
+    nixPath = config.nix.settings.nix-path;
 
     gc.automatic = pkgs.lib.mkDefault true;
     gc.options = pkgs.lib.mkDefault "--delete-older-than 14d";