diff --git a/deploy.sh b/deploy.sh
index 9cd3c57..6695139 100755
--- a/deploy.sh
+++ b/deploy.sh
@@ -23,7 +23,7 @@ cleanup() {
 compatibility_check() {
   TEST_FAIL=0
 
-  if [[ -r /etc/os-release && $(grep -qi '^ID=nixos\b' /etc/os-release) ]]; then
+  if [[ -r /etc/os-release ]] && grep -qi '^ID=nixos\b' /etc/os-release; then
     echod "\n ✅ NixOS system detected."
   else
     ((TEST_FAIL++))