added individual host variables and pkgs-unstable

hosts/common/default.nix

@@ -1,6 +1,6 @@
-{ pkgs, configVars, ... }:
+{ pkgs, hostname, ... }:
 {
-  networking.hostName = configVars.hostname;
+  networking.hostName = hostname;
   imports = [
     ./nix-ld.nix
     ./boot.nix

hosts/default.nix

@@ -1,7 +1,7 @@
-{ pkgs, configVars, ... }:
+{ pkgs, hostname, ... }:
 {
   imports = [
     ./common
-    ./${configVars.hostname}
+    ./${hostname}
   ];
 }