diff --git a/checkout.sh b/checkout.sh
index 808b5be94d08..261c5b0c5ecd 100755
--- a/checkout.sh
+++ b/checkout.sh
@@ -1 +1,2 @@
+#!/usr/bin/env sh
 carthage checkout --no-use-binaries
diff --git a/update.sh b/update.sh
index 01fc2ad16761..51b18dcff6ec 100755
--- a/update.sh
+++ b/update.sh
@@ -1 +1,2 @@
+#!/usr/bin/env sh
 carthage update --no-use-binaries --no-build