diff --git a/test/compile-test.sh b/test/compile-test.sh
index 9a2f5e0..854d527 100755
--- a/test/compile-test.sh
+++ b/test/compile-test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/hasher-test.sh b/test/hasher-test.sh
index c90fcc9..bfeab44 100755
--- a/test/hasher-test.sh
+++ b/test/hasher-test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
@@ -304,7 +304,7 @@ done
 #
 
 function expand_string() {
-	if [[ "$1" == 0x* ]]
+	if [ "$1" == 0x* ]
 	then
 		printf "$(echo -n "${1#0x}" | sed 's/\(..\)/\\x\1/g')"
 	else
diff --git a/test/kcapi-convenience.sh b/test/kcapi-convenience.sh
index d1cb110..d4ca19e 100755
--- a/test/kcapi-convenience.sh
+++ b/test/kcapi-convenience.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/kcapi-dgst-test.sh b/test/kcapi-dgst-test.sh
index 0ad5ed3..00b3e8a 100755
--- a/test/kcapi-dgst-test.sh
+++ b/test/kcapi-dgst-test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/kcapi-enc-test-large.sh b/test/kcapi-enc-test-large.sh
index 4a244d9..d464f14 100755
--- a/test/kcapi-enc-test-large.sh
+++ b/test/kcapi-enc-test-large.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/kcapi-enc-test.sh b/test/kcapi-enc-test.sh
index 3ace39c..e788dbd 100755
--- a/test/kcapi-enc-test.sh
+++ b/test/kcapi-enc-test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/kcapi-fuzz-test.sh b/test/kcapi-fuzz-test.sh
index c44d30b..51f968a 100755
--- a/test/kcapi-fuzz-test.sh
+++ b/test/kcapi-fuzz-test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/libtest.sh b/test/libtest.sh
index 74ff8ce..cd6198b 100644
--- a/test/libtest.sh
+++ b/test/libtest.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #
@@ -74,7 +74,7 @@ color()
 {
 	bg=0
 	echo -ne "\033[0m"
-	while [[ $# -gt 0 ]]; do
+	while [ $# -gt 0 ]; do
 		code=0
 		case $1 in
 			black) code=30 ;;
@@ -90,7 +90,9 @@ color()
 			reset|off|default) code=0 ;;
 			bold|bright) code=1 ;;
 		esac
-		[[ $code == 0 ]] || echo -ne "\033[$(printf "%02d" $((code+bg)))m"
+		if [ $code == 0 ]; then
+			echo -ne "\033[$(printf "%02d" $((code+bg)))m"
+		fi
 		shift
 	done
 }
diff --git a/test/test-invocation.sh b/test/test-invocation.sh
index 61c0a3d..197234a 100755
--- a/test/test-invocation.sh
+++ b/test/test-invocation.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2016 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/test.sh b/test/test.sh
index b889335..13636e8 100755
--- a/test/test.sh
+++ b/test/test.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2014 - 2022, Stephan Mueller <smueller@chronox.de>
 #
diff --git a/test/virttest.sh b/test/virttest.sh
index c3c77be..c717111 100755
--- a/test/virttest.sh
+++ b/test/virttest.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/sh
 #
 # Copyright (C) 2017 - 2022, Stephan Mueller <smueller@chronox.de>
 #