diff --git a/src/script.sh b/src/script.sh
index 601db9e..915d89a 100644
--- a/src/script.sh
+++ b/src/script.sh
@@ -1,8 +1,13 @@
 #!/bin/sh
 
-# works best on busybox ash
-
-set -efx -o pipefail
+## dash does not support pipefail
+# this does not work in `dash script.sh`
+DASH=$(readlink -f "/bin/sh" | grep "dash" || [ $? = 1 ])
+if [ -n "$DASH" ]; then
+  set -efx
+else
+  set -efx -o pipefail
+fi
 
 alias curl="curl -L"
 alias mkdir="mkdir -p"