diff --git a/util/cairo_include.sh b/util/cairo_include.sh
index 57ec476..fae1719 100755
--- a/util/cairo_include.sh
+++ b/util/cairo_include.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 
 # Make pkg-config lookup include files from the build directory.
 export PKG_CONFIG_PATH=$(cd "$(dirname "$0")"; pwd)/../build_cairo/lib/pkgconfig;
diff --git a/util/has_cairo_freetype.sh b/util/has_cairo_freetype.sh
index 91bdd47..7c7e583 100755
--- a/util/has_cairo_freetype.sh
+++ b/util/has_cairo_freetype.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 
 has_freetype() {
   pkg-config cairo --cflags-only-I | grep freetype2
diff --git a/util/has_lib.sh b/util/has_lib.sh
index 27911b6..6419e24 100755
--- a/util/has_lib.sh
+++ b/util/has_lib.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 has_lib() {
   local regex="lib$1.+(so|dylib)"
 
diff --git a/util/lib_lookup.sh b/util/lib_lookup.sh
index 8f19ce2..13c4f9c 100755
--- a/util/lib_lookup.sh
+++ b/util/lib_lookup.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/usr/bin/env sh
 
 # Make pkg-config lookup include files from the build directory.
 export PKG_CONFIG_PATH=$(cd "$(dirname "$0")"; pwd)/../build_cairo/lib/pkgconfig;