diff --git a/postinstall.sh b/postinstall.sh
index a01cfda..e7547c7 100644
--- a/postinstall.sh
+++ b/postinstall.sh
@@ -35,7 +35,7 @@ sudo /etc/init.d/nginx start
   echo '        }'
   echo '    }'
   echo '}'
-} >> /etc/nginx/nginx.conf
+} >| /etc/nginx/nginx.conf
 
 echo "Starting pigpiod daemon"