diff --git a/sh/alias/shell.sh b/sh/alias/shell.sh
index 4b0949b..d6f5801 100644
--- a/sh/alias/shell.sh
+++ b/sh/alias/shell.sh
@@ -17,7 +17,7 @@ x() {
 		"${@}"
 }
 
-[ "$(rwx_shell)" = "bash" ] || return
+[ "${RWX_SHELL}" = "bash" ] || return
 
 # shellcheck disable=SC3033
 ..() {
diff --git a/sh/shell.sh b/sh/shell.sh
index 54284c6..4f0db9b 100644
--- a/sh/shell.sh
+++ b/sh/shell.sh
@@ -1,6 +1,6 @@
 _rwx_shell_color() {
 	local code="${1}"
-	case "$(rwx_shell)" in
+	case "${RWX_SHELL}" in
 	"bash")
 		printf "\x01\e[0"
 		if [ -n "${code}" ]; then
@@ -33,7 +33,7 @@ rwx_shell_configure() {
 	PS1="\$(rwx_shell_prompt \${?})"
 	PS2="├ "
 	# specific
-	case "$(rwx_shell)" in
+	case "${RWX_SHELL}" in
 	"bash")
 		# completion
 		local root="/usr/share/bash-completion"