diff --git a/nixos/boxes/foureighty/default.nix b/nixos/boxes/foureighty/default.nix
index 30f67d9f..2008e49c 100644
--- a/nixos/boxes/foureighty/default.nix
+++ b/nixos/boxes/foureighty/default.nix
@@ -6,6 +6,7 @@
     inputs.nixos-hardware.nixosModules.lenovo-thinkpad-t480
     ./hardware-configuration.nix
     ./tailscale-foureighty.nix
+    ./custom-kernel.nix
     ../../backups.nix
     ../../boot.nix
     ../../common.nix
diff --git a/nixos/boxes/vpsfree1/default.nix b/nixos/boxes/vpsfree1/default.nix
index 7abcd795..d6942bd2 100644
--- a/nixos/boxes/vpsfree1/default.nix
+++ b/nixos/boxes/vpsfree1/default.nix
@@ -14,6 +14,9 @@
     DefaultTimeoutStartSec=900s
   '';
 
+  boot.binfmt.emulatedSystems = [ "aarch64-linux" ];
   time.timeZone = "Europe/London";
+
+  nix.buildCores = 7;
 }
 
diff --git a/nixos/distributed-builds.nix b/nixos/distributed-builds.nix
index 92500ac3..ee622a12 100644
--- a/nixos/distributed-builds.nix
+++ b/nixos/distributed-builds.nix
@@ -11,6 +11,16 @@
       sshKey = "/home/cyryl/.ssh/id_ed25519";
       systems = [ "x86_64-linux" "aarch64-linux" ];
       maxJobs = 2;
+      speedFactor = 1;
+      supportedFeatures = [ "kvm" "big-parallel" ];
+      mandatoryFeatures = [ ];
+    }
+    {
+      hostName = "vpsfree1";
+      sshUser = "nix-builder";
+      sshKey = "/home/cyryl/.ssh/id_ed25519";
+      systems = [ "x86_64-linux" "aarch64-linux" ];
+      maxJobs = 2;
       speedFactor = 2;
       supportedFeatures = [ "kvm" "big-parallel" ];
       mandatoryFeatures = [ ];