diff --git a/lib/crushpng.sh b/lib/crushpng.sh
index 436f38f..302ebf1 100755
--- a/lib/crushpng.sh
+++ b/lib/crushpng.sh
@@ -2,7 +2,10 @@
 
 set -ex
 
-[ "$(wc -c $1 | awk '{print $1}')" -le $3 ] && (cp $1 $2; exit 0)
+if [ "$(wc -c $1 | awk '{print $1}')" -le $3 ]; then
+    cp $1 $2
+    exit 0
+fi
 
 for i in $(seq 100 -1 0); do
   cat $1 | pngquant --quality 0-$i - > $2