pasteable command for trying without rebuilding vm

paste

@@ -0,0 +1,59 @@
+declare substituters trusted_public_keys drv_path
+
+host="root@fedi203.abundos.eu"
+
+sshOpts=(
+  -o BatchMode=yes
+  -o StrictHostKeyChecking=no
+)
+
+command=(nix-instantiate --expr '
+  let
+    sources = import ./npins;
+    configuration = {
+      imports = [
+        ./infra/common/proxmox-qemu-vm.nix
+        ./infra/common/nixos/users.nix
+        ./deployment/check/common/sharedOptions.nix
+        ./deployment/check/common/targetNode.nix
+        "${sources.disko}/module.nix"
+      ];
+    };
+    eval = import "${sources.nixpkgs}/nixos/lib/eval-config.nix" {
+      system = builtins.currentSystem;
+      specialArgs = {
+        inherit sources;
+      };
+      modules = [ configuration ];
+    };
+    os = {
+      inherit (eval) pkgs config options;
+      system = eval.config.system.build.toplevel;
+      inherit (eval.config.system.build) vm vmWithBootLoader;
+    };
+  in
+  {
+    substituters = builtins.concatStringsSep " " os.config.nix.settings.substituters;
+    trusted_public_keys = builtins.concatStringsSep " " os.config.nix.settings.trusted-public-keys;
+    drv_path = os.config.system.build.toplevel.drvPath;
+    out_path = os.config.system.build.toplevel;
+  }
+')
+
+buildArgs=(
+  --option extra-binary-caches https://cache.nixos.org/
+  --option substituters "$substituters"
+  --option trusted-public-keys "$trusted_public_keys"
+)
+
+"${command[@]}" -A out_path
+
+json="$("${command[@]}" --eval --strict --json)"
+
+eval "export $(echo $json | jq -r 'to_entries | map("\(.key)=\(.value)") | @sh')"
+
+outPath=$(nix-store --realize "$drv_path" "${buildArgs[@]}")
+
+NIX_SSHOPTS="${sshOpts[*]}" nix-copy-closure --to "$host" "$outPath" --gzip --use-substitutes
+
+ssh "${sshOpts[@]}" "$host" "nix-env --profile /nix/var/nix/profiles/system --set $outPath; $outPath/bin/switch-to-configuration switch"