diff --git a/services/nix-cache/build-flakes.sh b/services/nix-cache/build-flakes.sh
index d3de19f..99aacde 100644
--- a/services/nix-cache/build-flakes.sh
+++ b/services/nix-cache/build-flakes.sh
@@ -7,8 +7,7 @@ git pull
 echo "Starting nixos-servers builds"
 for host in $(nix flake show --json| jq -r '.nixosConfigurations | keys[]'); do
   echo "Building $host"
-  nixos-rebuild --verbose -L --flake ".#$host" build
-  if [ $? -ne 0 ]; then
+  if ! nixos-rebuild --verbose -L --flake ".#$host" build; then
     echo "Build failed for $host"
     cat <<EOF | curl --data-binary @- "https://pushgw.home.2rjus.net/metrics/job/$JOB_NAME"
 # TYPE build_flakes_error gauge
@@ -30,8 +29,7 @@ echo "Building gunter"
 cd /root/nixos
 git pull
 host="gunter"
-nixos-rebuild --verbose -L --flake ".#gunter" build
-if [ $? -ne 0 ]; then
+if ! nixos-rebuild --verbose -L --flake ".#gunter" build; then
     echo "Build failed for $host"
     cat <<EOF | curl --data-binary @- "https://pushgw.home.2rjus.net/metrics/job/$JOB_NAME"
 # TYPE build_flakes_error gauge