diff --git a/lib/build-clan/default.nix b/lib/build-clan/default.nix
index 244fca4f..eaccc25e 100644
--- a/lib/build-clan/default.nix
+++ b/lib/build-clan/default.nix
@@ -4,6 +4,8 @@
 , machines ? { } # allows to include machine-specific modules i.e. machines.${name} = { ... }
 , clanName # Needs to be (globally) unique, as this determines the folder name where the flake gets downloaded to.
 , clanIcon ? null # A path to an icon to be used for the clan, should be the same for all machines
+, pkgsForSystem ? (_system: null) # A map from arch to pkgs, if specified this nixpkgs will be only imported once for each system.
+  # This improves performance, but all nipxkgs.* options will be ignored.
 }:
 let
   machinesDirs = lib.optionalAttrs (builtins.pathExists "${directory}/machines") (builtins.readDir (directory + /machines));
@@ -78,13 +80,23 @@ let
   configsPerSystem = builtins.listToAttrs
     (builtins.map
       (system: lib.nameValuePair system
-        (lib.mapAttrs (name: _: nixosConfiguration { inherit name system; }) allMachines))
+        (lib.mapAttrs
+          (name: _: nixosConfiguration {
+            inherit name system;
+            pkgs = pkgsForSystem system;
+          })
+          allMachines))
       supportedSystems);
 
   configsFuncPerSystem = builtins.listToAttrs
     (builtins.map
       (system: lib.nameValuePair system
-        (lib.mapAttrs (name: _: args: nixosConfiguration (args // { inherit name system; })) allMachines))
+        (lib.mapAttrs
+          (name: _: args: nixosConfiguration (args // {
+            inherit name system;
+            pkgs = pkgsForSystem system;
+          }))
+          allMachines))
       supportedSystems);
 in
 {
diff --git a/pkgs/clan-cli/clan_cli/vms/run.py b/pkgs/clan-cli/clan_cli/vms/run.py
index abeb28f9..46fedfe0 100644
--- a/pkgs/clan-cli/clan_cli/vms/run.py
+++ b/pkgs/clan-cli/clan_cli/vms/run.py
@@ -201,5 +201,4 @@ def run_command(args: argparse.Namespace) -> None:
 
 def register_run_parser(parser: argparse.ArgumentParser) -> None:
     parser.add_argument("machine", type=str, help="machine in the flake to run")
-    parser.add_argument("--flake-url", type=str, help="flake url")
     parser.set_defaults(func=run_command)