flake: factorize shared modules

flake.nix

@@ -53,6 +53,11 @@
         home-manager.users.alarsyo = import ./home;
         home-manager.verbose = true;
       };
+      nix-path = {
+        nix.nixPath = [
+          "nixpkgs=${inputs.nixpkgs}"
+        ];
+      };
     };
 
     nixosConfigurations =
@@ -69,6 +74,10 @@
             };
           })
         ];
+        sharedModules = [
+          home-manager.nixosModule
+          { nixpkgs.overlays = shared_overlays; }
+        ] ++ (nixpkgs.lib.attrValues self.nixosModules);
       in {
 
         poseidon = nixpkgs.lib.nixosSystem rec {
@@ -76,9 +85,6 @@
           modules = [
             ./poseidon.nix
 
-            home-manager.nixosModule
-            self.nixosModules.home
-
             {
               nixpkgs.overlays = [
                 (self: super: {
@@ -93,9 +99,9 @@
                     python3 = self.fastPython3;
                   };
                 })
-              ] ++ shared_overlays;
-            }
               ];
+            }
+          ] ++ sharedModules;
         };
 
         boreal = nixpkgs.lib.nixosSystem rec {
@@ -103,9 +109,6 @@
           modules = [
             ./boreal.nix
 
-            home-manager.nixosModule
-            self.nixosModules.home
-
             {
               nixpkgs.overlays = [
                 inputs.emacs-overlay.overlay
@@ -116,9 +119,9 @@
                 # (self: super: {
                 #   stdenv = super.impureUseNativeOptimizations super.stdenv;
                 # })
-              ] ++ shared_overlays;
-            }
               ];
+            }
+          ] ++ sharedModules;
         };
 
         zephyrus = nixpkgs.lib.nixosSystem rec {
@@ -130,15 +133,12 @@
             inputs.nixos-hardware.nixosModules.common-pc-laptop
             inputs.nixos-hardware.nixosModules.common-pc-ssd
 
-            home-manager.nixosModule
-            self.nixosModules.home
-
             {
               nixpkgs.overlays = [
                 inputs.emacs-overlay.overlay
-              ] ++ shared_overlays;
-            }
               ];
+            }
+          ] ++ sharedModules;
         };
 
       };