core: pin registry by ref

Users may wish to change the default value of override and nixos
inputs. If they do so, we want the registry listing to reflect the
proper ref names afterwards.

Also create a shell alias to easily search every flake in nix.registry.

hosts/default.nix

@@ -1,11 +1,12 @@
-{ lib
+{ extern
+, home
+, lib
 , nixos
-, override
 , nixos-hardware
+, override
 , pkgs
 , self
 , system
-, extern
 , ...
 }:
 let
@@ -36,24 +37,52 @@ let
                 modules;
             };
 
-          global = {
+          global =
+            let
+              inherit (lock) nodes;
+
+              lock = builtins.fromJSON (builtins.readFile ../flake.lock);
+            in
+            {
               home-manager.useGlobalPkgs = true;
               home-manager.useUserPackages = true;
 
               hardware.enableRedistributableFirmware = lib.mkDefault true;
 
               networking.hostName = hostName;
+
               nix.nixPath = [
-              "nixos-unstable=${override}"
-              "nixos=${nixos}"
                 "nixpkgs=${nixos}"
+                "nixos-config=${self}/compat/nixos"
+                "home-manager=${home}"
               ];
 
               nixpkgs = { inherit pkgs; };
 
               nix.registry = {
-              nixflk.flake = self;
-              nixpkgs.flake = nixos;
+                flk.flake = self;
+
+                nixos = {
+                  exact = true;
+                  from = nodes.nixos.original;
+                  to = {
+                    inherit (nixos) lastModified narHash rev;
+
+                    path = override.outPath;
+                    type = "path";
+                  };
+                };
+
+                override = {
+                  exact = true;
+                  from = nodes.override.original;
+                  to = {
+                    inherit (override) lastModified narHash rev;
+
+                    path = override.outPath;
+                    type = "path";
+                  };
+                };
               };
 
               system.configurationRevision = lib.mkIf (self ? rev) self.rev;

profiles/core/default.nix

@@ -65,8 +65,8 @@ in
         nr = "np remove";
         ns = "n search --no-update-lock-file";
         nf = "n flake";
-        nepl = "n repl '<nixos>'";
-        srch = "ns nixpkgs";
+        nepl = "n repl '<nixpkgs>'";
+        srch = "nsni";
         nrb = ifSudo "sudo nixos-rebuild";
         mn = ''
           manix "" | grep '^# ' | sed 's/^# \(.*\) (.*/\1/;s/ (.*//;s/^# //' | sk --preview="manix '{}'" | xargs manix
@@ -93,7 +93,20 @@ in
         dn = ifSudo "s systemctl stop";
         jtl = "journalctl";
 
-      };
+      } // lib.mapAttrs'
+        (n: v:
+          let
+            prefix = lib.concatStrings (lib.take 2 (lib.stringToCharacters n));
+            ref = from:
+              if from ? ref
+              then "ns ${from.id}/${from.ref}"
+              else "ns ${from.id}";
+          in
+          lib.nameValuePair
+            "ns${prefix}"
+            (ref v.from)
+        )
+        config.nix.registry;
 
   };