diff --git a/commands.beta/is-suffix b/commands.beta/is-suffix
index a7ff4191c..a14cec98a 100755
--- a/commands.beta/is-suffix
+++ b/commands.beta/is-suffix
@@ -9,10 +9,14 @@ function is_suffix() (
 	haystack="${2:?"USAGE: is-suffix <needle> <HAYSTACK>"}"
 
 	# oldschool way:
-	# echo-regexp -q "$needle\$" -- "$haystack"
+	# echo-regexp -q "$needle\$" -- "$haystack" <-- doesn't work, as $needle is not escaped
+	# [[ $haystack =~ ^.*$needle$ ]] <-- doesn't work, as $needle is not escaped
 
 	# better way:
-	[[ $needle == "${haystack:${#needle}*-1}" ]]
+	local suffix
+	local -i length=${#needle}
+	suffix="$(__substr "$haystack" $((length * -1)))"
+	[[ $needle == "$suffix" ]]
 	return
 )
 
diff --git a/commands.beta/is-dir b/commands.deprecated/is-dir
similarity index 66%
rename from commands.beta/is-dir
rename to commands.deprecated/is-dir
index 450a75f12..814ff7ca5 100755
--- a/commands.beta/is-dir
+++ b/commands.deprecated/is-dir
@@ -2,6 +2,7 @@
 
 function is_dir() (
 	source "$DOROTHY/sources/bash.bash"
+	dorothy-warnings add --code='is-dir' --bold=' has been deprecated in favor of ' --code='is-directory'
 
 	local dir="$1"
 	[[ -d $dir ]]
diff --git a/commands/ask b/commands/ask
index 15865c36b..d6169c297 100755
--- a/commands/ask
+++ b/commands/ask
@@ -315,7 +315,7 @@ function ask_() (
 		fi
 
 		ASKED='yes' # not local
-		while true; do
+		while :; do
 			# reset
 			__read_status=0
 			READ_RESULT=''
diff --git a/commands/brew b/commands/brew
index 4089c4992..e7886b997 100755
--- a/commands/brew
+++ b/commands/brew
@@ -53,7 +53,7 @@ function brew_() (
 		fi
 		return 22 # EINVAL 22 Invalid argument
 	}
-	if [[ -z $bin ]] || [[ $* == '--help' ]]; then
+	if [[ -z $bin || $* == '--help' ]]; then
 		help >/dev/stderr
 	fi
 
diff --git a/commands/choose b/commands/choose
index 1850099f7..2ab3b7602 100755
--- a/commands/choose
+++ b/commands/choose
@@ -1402,8 +1402,7 @@ function choose_() (
 		if [[ $option_required == 'yes' ]]; then
 			# if required, and trying to do proceed without items, then go back to choose and send a bell
 			if
-				[[ ($selected_count -eq 0 && ($new == 'confirm' || $new == 'confirmed')) ||
-					($fallbacks_count -eq 0 && $new == 'cancel') ]]
+				[[ ($selected_count -eq 0 && $new =~ ^(confirm|confirmed)$) || ($fallbacks_count -eq 0 && $new == 'cancel') ]]
 			then
 				menu_skip_render='yes'
 				menu_mode='choose'
@@ -1902,7 +1901,7 @@ function choose_() (
 		# action
 		show_cursor_on_exit
 		__print_string "$style__alternative_screen_buffer" >"$terminal_device_file"
-		while true; do
+		while :; do
 			# (re-)render the menu?
 			if [[ $menu_skip_render == 'no' ]]; then
 				render_menu
@@ -2037,7 +2036,7 @@ function choose_() (
 						else
 							action_all
 						fi
-					elif [[ $key == 'insert' || $key == '+' ]]; then
+					elif [[ $key =~ ^(insert|\+)$ ]]; then
 						action_select_and_next
 					elif [[ $key == '-' ]]; then
 						action_select_and_prior
diff --git a/commands/config-edit b/commands/config-edit
index 49bc5c192..547cc7c43 100755
--- a/commands/config-edit
+++ b/commands/config-edit
@@ -302,7 +302,7 @@ function config_edit() (
 	else
 		expected=''
 	fi
-	while true; do
+	while :; do
 		lines="$("$option_searcher" "$option_needle" || :)"
 		eval_capture --statusvar=status -- "$option_comparer" "$lines" "$expected"
 		if [[ $status -eq 0 ]]; then
diff --git a/commands/config-helper b/commands/config-helper
index 7a0839d48..78d8b5319 100755
--- a/commands/config-helper
+++ b/commands/config-helper
@@ -265,7 +265,7 @@ function config_helper() (
 			esac
 
 			# adjust quote based on file
-			if [[ $option_quote == 'generic' || $option_quote == 'yes' ]]; then
+			if [[ $option_quote =~ ^(generic|yes)$ ]]; then
 				if [[ $option_file == *'.bash' || $option_file == *'.sh' ]]; then
 					option_quote='bash'
 				else
@@ -370,7 +370,7 @@ function config_helper() (
 					value="$(echo-escape-bash -- "$value")"
 				elif [[ $option_quote == 'command' ]]; then
 					value="$(echo-escape-command -- "$value")"
-				elif [[ $option_quote == 'generic' || $option_quote == 'yes' ]]; then
+				elif [[ $option_quote =~ ^(generic|yes)$ ]]; then
 					value="$(echo-quote -- "$value")"
 				fi
 				addition="$field=$value"
diff --git a/commands/confirm b/commands/confirm
index fe7a701d3..b23406039 100755
--- a/commands/confirm
+++ b/commands/confirm
@@ -145,7 +145,7 @@ function confirm_() (
 	done
 
 	# mode
-	if [[ $option_mode == 'positive' || $option_mode == 'negative' ]]; then
+	if [[ $option_mode =~ ^(positive|negative)$ ]]; then
 		if [[ -z $option_timeout ]]; then
 			option_timeout='60' # one minute
 		fi
@@ -350,7 +350,7 @@ function confirm_() (
 		question_confirm_and_input_lines=''
 		if [[ $terminal_tty_support == 'no' ]]; then
 			for key in "${keys[@]}"; do
-				if [[ $key == 'enter' || $key == 'line-buffer' ]]; then
+				if [[ $key =~ ^(enter|line-buffer)$ ]]; then
 					question_confirm_and_input_lines+=$'\n'
 				fi
 			done
@@ -405,19 +405,20 @@ function confirm_() (
 				fi
 				;;
 			'left' | 'right' | 'up' | 'down')
+				# Yes the differences in combination is intentional... try it!
 				if [[ -z $selected_index || $selectable_count -eq 1 ]]; then
-					if [[ $key == 'right' || $key == 'up' ]]; then
+					if [[ $key =~ ^(right|up)$ ]]; then
 						selected_index="$selectable_last"
-					elif [[ $key == 'left' || $key == 'down' ]]; then
+					elif [[ $key =~ ^(left|down)$ ]]; then
 						selected_index=0
 					fi
-				elif [[ $key == 'left' || $key == 'up' ]]; then
+				elif [[ $key =~ ^(left|up)$ ]]; then
 					if [[ $selected_index -eq 0 ]]; then
 						selected_index="$selectable_last"
 					else
 						selected_index="$((selected_index - 1))"
 					fi
-				elif [[ $key == 'right' || $key == 'down' ]]; then
+				elif [[ $key =~ ^(right|down)$ ]]; then
 					if [[ $selected_index -eq $selectable_last ]]; then
 						selected_index=0
 					else
diff --git a/commands/echo-lines b/commands/echo-lines
index 1290a71f7..29a4d20c3 100755
--- a/commands/echo-lines
+++ b/commands/echo-lines
@@ -261,7 +261,7 @@ function echo_lines() (
 		function on_input {
 			items+=("$option_prefix$(echo-escape-command -- "$1")$option_suffix")
 		}
-	elif [[ $option_quote == 'generic' || $option_quote == 'yes' ]]; then
+	elif [[ $option_quote =~ ^(generic|yes)$ ]]; then
 		function on_input {
 			items+=("$option_prefix$(echo-quote -- "$1")$option_suffix")
 		}
diff --git a/commands/fs-temp b/commands/fs-temp
index eeacb551a..001c51a66 100755
--- a/commands/fs-temp
+++ b/commands/fs-temp
@@ -123,7 +123,7 @@ function fs_temp() (
 	for directory in "${option_directories[@]}"; do
 		if [[ -z $directory ]]; then
 			# generate a non-existent directory name
-			while true; do
+			while :; do
 				directory="$option_prefix$(get-random-number)$option_suffix"
 				if is-missing -- "$root/$directory"; then
 					break
@@ -144,7 +144,7 @@ function fs_temp() (
 		for file in "${option_files[@]}"; do
 			if [[ -z $file ]]; then
 				# generate a non-existent filename
-				while true; do
+				while :; do
 					file="$option_prefix$(get-random-number)$option_suffix$option_extension"
 					if is-missing -- "$root/$file"; then
 						break
diff --git a/commands/is-empty-value b/commands/is-empty-value
index 90fcb5319..67e3e3de7 100755
--- a/commands/is-empty-value
+++ b/commands/is-empty-value
@@ -55,10 +55,7 @@ function is_empty_value() (
 	local value
 	for value in "${option_inputs[@]}"; do
 		# check for empty values, or check for an empty string
-		if [[ -z $value ||
-			$value == 'null' || $value == 'NULL' ||
-			$value == 'void' || $value == 'VOID' ||
-			$value == 'undefined' || $value == 'UNDEFINED' ]] || is-empty-string -- "$value"; then
+		if [[ -z $value || $value =~ ^(null|NULL|void|VOID|undefined|UNDEFINED)$ ]] || is-empty-string -- "$value"; then
 			: # all good, conntinue
 		else
 			return 1 # not good
diff --git a/commands/mount-helper b/commands/mount-helper
index 956cbf2ca..57ee8262d 100755
--- a/commands/mount-helper
+++ b/commands/mount-helper
@@ -1490,7 +1490,7 @@ function mount_helper() (
 
 			# it exists, check if mounted
 			local local_check_status=''
-			while true; do
+			while :; do
 				# update check
 				eval_capture -- do_check
 				local_check_status="$SHARED_CHECK_STATUS"
diff --git a/commands/setup-git b/commands/setup-git
index c123e5cb6..2d2a7df55 100755
--- a/commands/setup-git
+++ b/commands/setup-git
@@ -112,7 +112,7 @@ function setup_git() (
 	fi
 
 	# handle deprecations
-	if [[ $GPG_SIGNING_KEY == 'op' || $GPG_SIGNING_KEY == '1password' ]]; then
+	if [[ $GPG_SIGNING_KEY =~ ^(op|1password)$ ]]; then
 		GPG_SIGNING_AGENT='op'
 		dorothy-config 'git.bash' -- \
 			--field='GPG_SIGNING_KEY' --replace= \
diff --git a/commands/setup-linux b/commands/setup-linux
index 7cc88dae3..2c9a5e275 100755
--- a/commands/setup-linux
+++ b/commands/setup-linux
@@ -358,7 +358,7 @@ function setup_linux() (
 					-- "do_${item}_clean"
 			fi
 		done
-	elif [[ $action == 'install' || $action == 'update' ]]; then
+	elif [[ $action =~ ^(install|update)$ ]]; then
 		# log
 		echo-style --h1="$title"
 
diff --git a/commands/setup-mac b/commands/setup-mac
index 6873822ce..31656bb8d 100755
--- a/commands/setup-mac
+++ b/commands/setup-mac
@@ -58,7 +58,7 @@ function setup_mac() (
 	# action
 	if [[ $action == 'clean' ]]; then
 		setup-mac-brew clean
-	elif [[ $action == 'install' || $action == 'update' ]]; then
+	elif [[ $action =~ ^(install|update)$ ]]; then
 		# log
 		echo-style --h1="$title"
 
diff --git a/commands/setup-system b/commands/setup-system
index e00ddc4ca..f469e42e3 100755
--- a/commands/setup-system
+++ b/commands/setup-system
@@ -58,7 +58,7 @@ function setup_system() (
 	echo-style --h1="$title"
 
 	# action
-	if [[ $action == 'install' || $action == 'update' ]]; then
+	if [[ $action =~ ^(install|update)$ ]]; then
 		# pre-requisites
 		is-internet-working
 
diff --git a/commands/setup-util-xcode b/commands/setup-util-xcode
index d9fa68795..bf0075f62 100755
--- a/commands/setup-util-xcode
+++ b/commands/setup-util-xcode
@@ -30,7 +30,7 @@ function setup_util_xcode() (
 
 	# check if xcode exists
 	local xcode xcodebuild xcodesdk
-	while true; do
+	while :; do
 		# prerequisites
 		setup-util-apple-rosetta --quiet="$option_quiet"
 		setup-util-apple-cli-tools --quiet="$option_quiet"
diff --git a/commands/symlink-helper b/commands/symlink-helper
index fba0801c3..01848194f 100755
--- a/commands/symlink-helper
+++ b/commands/symlink-helper
@@ -106,7 +106,7 @@ function symlink_helper() (
 
 	# ensure validity of existing path
 	local original
-	while true; do
+	while :; do
 		# ensure both paths are not relative paths, otherwise weird things will happen
 		option_existing="$(fs-absolute -- "$option_existing")"
 		option_symlink="$(fs-absolute -- "$option_symlink")"
diff --git a/commands/waiter b/commands/waiter
index 2167fb8d8..39bc2ae80 100755
--- a/commands/waiter
+++ b/commands/waiter
@@ -132,7 +132,7 @@ function waiter_() (
 
 	# wait
 	local -i minutes delta waited=0
-	while true; do
+	while :; do
 		if [[ -n $option_exists && -e $option_exists ]]; then
 			option_status=0
 			break
diff --git a/sources/bash.bash b/sources/bash.bash
index db5ceeb67..aaedea8de 100644
--- a/sources/bash.bash
+++ b/sources/bash.bash
@@ -241,7 +241,7 @@ function __sudo_mkdirp {
 	return "$status"
 }
 
-# bash < 4.2 doesn't support negative lengths, bash >= 4.2 supports negative start indexes however it requires a preceeding space if done directly: ${var: -1}
+# bash < 4.2 doesn't support negative lengths, bash >= 4.2 supports negative start indexes however it requires a preceeding space or wrapped parenthesis if done directly: ${var: -1} or ${var:(-1)}
 # the bash >= 4.2 behaviour returns empty string if negative start index is out of bounds, rather than the entire string, which is unintuitive: v=12345; s=-6; echo "${v:s}"
 # function __substr_native {
 # 	local string="$1" start="${2:-0}" length="${3-}"
@@ -344,7 +344,7 @@ if [[ -z ${BASH_VERSION_CURRENT-} ]]; then
 	if [[ $BASH_VERSION_MAJOR -eq 5 ]]; then
 		IS_BASH_VERSION_OUTDATED='no'
 		function __require_upgraded_bash {
-			true
+			:
 		}
 	else
 		IS_BASH_VERSION_OUTDATED='yes'
@@ -377,7 +377,7 @@ shopt -s huponexit
 # bash v4.2:    lastpipe    If set, and job control is not active, the shell runs the last command of a pipeline not executed in the background in the current shell environment.
 if shopt -s lastpipe 2>/dev/null; then
 	function __require_lastpipe {
-		true
+		:
 	}
 else
 	function __require_lastpipe {
@@ -644,7 +644,7 @@ shopt -s nullglob
 # bash v4: globstar: If set, the pattern ‘**’ used in a filename expansion context will match all files and zero or more directories and subdirectories. If the pattern is followed by a ‘/’, only directories and subdirectories match.
 if shopt -s globstar 2>/dev/null; then
 	function __require_globstar {
-		true
+		:
 	}
 else
 	function __require_globstar {
@@ -656,7 +656,7 @@ fi
 # bash v5: extglob: If set, the extended pattern matching features described above (see Pattern Matching) are enabled.
 if shopt -s extglob 2>/dev/null; then
 	function __require_extglob {
-		true
+		:
 	}
 else
 	function __require_extglob {