diff --git a/Vagrantfile b/Vagrantfile
index 586094ee579221cf0e65ceb4af359f1a7b1828fd..3914ede6915eafec3400349de96b1215fcc0382d 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -25,8 +25,13 @@
 # backwards compatibility). Please don't change it unless you know what
 # you're doing.
 Vagrant.configure("2") do |config|
-  config.vm.box = "debian/bullseye64"
+  config.vm.box = "debian/bookworm64"
   config.vm.hostname = "gimmecert-testing"
 
+  config.vm.provider "virtualbox" do |vb|
+    vb.memory = "1536"
+    vb.cpus = 2
+  end
+
   config.vm.provision "shell", path: "provision.sh"
 end
diff --git a/provision.sh b/provision.sh
index a08edb57f4d5a89fe6bcfcf08635f998de0bd0fe..7280f564a64538e4ac210eddce2def118fb5b6d7 100755
--- a/provision.sh
+++ b/provision.sh
@@ -84,7 +84,7 @@ for version in "${python_versions[@]}"; do
         sudo -i -u vagrant <<< "cd ${source}; ./configure --quiet"
 
         echo "Building..."
-        sudo -i -u vagrant make --quiet -C "$source" -j3
+        sudo -i -u vagrant make --quiet -C "$source" -j4
 
         echo "Installing..."
         make --quiet -C "$source" altinstall