diff --git a/clean_files.txt b/clean_files.txt
index f94b2dca..864acdc9 100644
--- a/clean_files.txt
+++ b/clean_files.txt
@@ -39,6 +39,13 @@ themes/barbuk
 themes/atomic
 themes/axin
 themes/base.theme.bash
+themes/bakke
+themes/binaryanomaly
+themes/bira
+themes/bobby
+themes/bobby-python
+themes/brainy
+themes/brunton
 
 # plugins
 #
diff --git a/themes/atomic/atomic.theme.bash b/themes/atomic/atomic.theme.bash
index fb4e15af..6bde6801 100644
--- a/themes/atomic/atomic.theme.bash
+++ b/themes/atomic/atomic.theme.bash
@@ -225,17 +225,15 @@ _atomic_completion() {
 	actions="show hide"
 	segments="battery clock exitcode python ruby scm sudo todo"
 	case "${_action}" in
-		show)
-			read -r -a COMPREPLY <<< "$(compgen -W "${segments}" -- "${cur}")"
-			return 0
-			;;
-		hide)
-			read -r -a COMPREPLY <<< "$(compgen -W "${segments}" -- "${cur}")"
+		show | hide)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "${segments}" -- "${cur}"))
 			return 0
 			;;
 	esac
 
-	read -r -a COMPREPLY <<< "$(compgen -W "${actions}" -- "${cur}")"
+	# shellcheck disable=SC2207
+	COMPREPLY=($(compgen -W "${actions}" -- "${cur}"))
 	return 0
 }
 
diff --git a/themes/bakke/bakke.theme.bash b/themes/bakke/bakke.theme.bash
index 1a4e0398..725350a0 100644
--- a/themes/bakke/bakke.theme.bash
+++ b/themes/bakke/bakke.theme.bash
@@ -1,4 +1,5 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
+
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
 SCM_THEME_PROMPT_PREFIX=" |"
@@ -13,10 +14,10 @@ RVM_THEME_PROMPT_PREFIX="|"
 RVM_THEME_PROMPT_SUFFIX="|"
 
 function prompt_command() {
-    #PS1="${bold_cyan}$(scm_char)${green}$(scm_prompt_info)${purple}$(ruby_version_prompt) ${yellow}\h ${reset_color}in ${green}\w ${reset_color}\n${green}→${reset_color} "
-    #PS1="\n${purple}\h: ${reset_color} ${green}\w\n${bold_cyan}$(scm_char)${green}$(scm_prompt_info) ${green}→${reset_color} "
-    #PS1="\n${cyan}\h: ${reset_color} ${yellow}\w\n${red}$(scm_char)${red}$(scm_prompt_info) ${green}→${reset_color} "
-    PS1="\n${cyan}\h:$(virtualenv_prompt) ${reset_color} ${yellow}\w ${green}$(scm_prompt_info)\n${reset_color}→ "
+	#PS1="${bold_cyan}$(scm_char)${green}$(scm_prompt_info)${purple}$(ruby_version_prompt) ${yellow}\h ${reset_color}in ${green}\w ${reset_color}\n${green}→${reset_color} "
+	#PS1="\n${purple}\h: ${reset_color} ${green}\w\n${bold_cyan}$(scm_char)${green}$(scm_prompt_info) ${green}→${reset_color} "
+	#PS1="\n${cyan}\h: ${reset_color} ${yellow}\w\n${red}$(scm_char)${red}$(scm_prompt_info) ${green}→${reset_color} "
+	PS1="\n${cyan}\h:$(virtualenv_prompt) ${reset_color} ${yellow}\w ${green}$(scm_prompt_info)\n${reset_color}→ "
 }
 
 safe_append_prompt_command prompt_command
diff --git a/themes/binaryanomaly/binaryanomaly.theme.bash b/themes/binaryanomaly/binaryanomaly.theme.bash
index 61573d54..f6740f35 100644
--- a/themes/binaryanomaly/binaryanomaly.theme.bash
+++ b/themes/binaryanomaly/binaryanomaly.theme.bash
@@ -1,80 +1,78 @@
-#!/usr/bin/env bash
-
+# shellcheck shell=bash
 
 # Detect whether a reboot is required
 function show_reboot_required() {
-  if [ ! -z "$_bf_prompt_reboot_info" ]; then
-    if [ -f /var/run/reboot-required ]; then
-      printf "Reboot required!"
-    fi
-  fi
+	if [ -n "$_bf_prompt_reboot_info" ]; then
+		if [ -f /var/run/reboot-required ]; then
+			printf "Reboot required!"
+		fi
+	fi
 }
 
 # Set different host color for local and remote sessions
 function set_host_color() {
-  # Detect if connection is through SSH
-  if [[ ! -z $SSH_CLIENT ]]; then
-    printf "${lime_yellow}"
-  else
-    printf "${light_orange}"
-  fi
+	# Detect if connection is through SSH
+	if [[ -n $SSH_CLIENT ]]; then
+		printf '%s' "${lime_yellow}"
+	else
+		printf '%s' "${light_orange}"
+	fi
 }
 
 # Set different username color for users and root
 function set_user_color() {
-  case $(id -u) in
-    0)
-      printf "${red}"
-      ;;
-    *)
-      printf "${cyan}"
-      ;;
-  esac
+	case $(id -u) in
+		0)
+			printf '%s' "${red}"
+			;;
+		*)
+			printf '%s' "${cyan}"
+			;;
+	esac
 }
 
 scm_prompt() {
-  CHAR=$(scm_char)
-  if [ $CHAR = $SCM_NONE_CHAR ]
-    then
-      return
-    else
-      echo "[$(scm_char)$(scm_prompt_info)]"
-  fi
+	CHAR=$(scm_char)
+	if [ "$CHAR" = "$SCM_NONE_CHAR" ]; then
+		return
+	else
+		echo "[$(scm_char)$(scm_prompt_info)]"
+	fi
 }
 
 # Define custom colors we need
 # non-printable bytes in PS1 need to be contained within \[ \].
 # Otherwise, bash will count them in the length of the prompt
 function set_custom_colors() {
-  dark_grey="\[$(tput setaf 8)\]"
-  light_grey="\[$(tput setaf 248)\]"
+	dark_grey="\[$(tput setaf 8)\]"
+	light_grey="\[$(tput setaf 248)\]"
 
-  light_orange="\[$(tput setaf 172)\]"
-  bright_yellow="\[$(tput setaf 220)\]"
-  lime_yellow="\[$(tput setaf 190)\]"
+	light_orange="\[$(tput setaf 172)\]"
+	bright_yellow="\[$(tput setaf 220)\]"
+	lime_yellow="\[$(tput setaf 190)\]"
 
-  powder_blue="\[$(tput setaf 153)\]"
+	powder_blue="\[$(tput setaf 153)\]"
 }
 
 __ps_time() {
-  echo "$(clock_prompt)${normal}\n"
+	printf '%s' "$(clock_prompt)${normal}\n"
 }
 
 function prompt_command() {
-  ps_reboot="${bright_yellow}$(show_reboot_required)${normal}\n"
+	ps_reboot="${bright_yellow}$(show_reboot_required)${normal}\n"
 
-  ps_username="$(set_user_color)\u${normal}"
-  ps_uh_separator="${dark_grey}@${normal}"
-  ps_hostname="$(set_host_color)\h${normal}"
+	ps_username="$(set_user_color)\u${normal}"
+	ps_uh_separator="${dark_grey}@${normal}"
+	ps_hostname="$(set_host_color)\h${normal}"
 
-  ps_path="${yellow}\w${normal}"
-  ps_scm_prompt="${light_grey}$(scm_prompt)"
+	ps_path="${yellow}\w${normal}"
+	ps_scm_prompt="${light_grey}$(scm_prompt)"
 
-  ps_user_mark="${normal} ${normal}"
-  ps_user_input="${normal}"
+	ps_user_mark="${normal} ${normal}"
+	ps_user_input="${normal}"
 
-  # Set prompt
-  PS1="$ps_reboot$(__ps_time)$ps_username$ps_uh_separator$ps_hostname $ps_path $ps_scm_prompt$ps_user_mark$ps_user_input"
+	# Set prompt
+	PS1="$ps_reboot$(__ps_time)$ps_username$ps_uh_separator$ps_hostname $ps_path $ps_scm_prompt$ps_user_mark$ps_user_input"
 }
 
 # Initialize custom colors
diff --git a/themes/bira/bira.theme.bash b/themes/bira/bira.theme.bash
index ad1db5c6..ae8f0efe 100644
--- a/themes/bira/bira.theme.bash
+++ b/themes/bira/bira.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 SCM_THEME_PROMPT_PREFIX=" ${yellow}‹"
 SCM_THEME_PROMPT_SUFFIX="›${reset_color}"
@@ -9,14 +9,14 @@ VIRTUALENV_THEME_PROMPT_SUFFIX="›${reset_color}"
 bold="\[\e[1m\]"
 
 if [ ${UID} -eq 0 ]; then
-  user_host="${bold_red}\u@\h${normal}${reset_color}"
+	user_host="${bold_red}\u@\h${normal}${reset_color}"
 else
-  user_host="${bold_green}\u@\h${normal}${reset_color}"
+	user_host="${bold_green}\u@\h${normal}${reset_color}"
 fi
 
 function prompt_command() {
-  local current_dir=" ${bold_blue}\w${normal}${reset_color}"
-  PS1="╭─${user_host}${current_dir}$(virtualenv_prompt)$(scm_prompt_info)\n╰─${bold}\\$ ${normal}"
+	local current_dir=" ${bold_blue}\w${normal}${reset_color}"
+	PS1="╭─${user_host}${current_dir}$(virtualenv_prompt)$(scm_prompt_info)\n╰─${bold}\\$ ${normal}"
 }
 
 safe_append_prompt_command prompt_command
diff --git a/themes/bobby-python/bobby-python.theme.bash b/themes/bobby-python/bobby-python.theme.bash
index 7aaea4e8..9144e251 100644
--- a/themes/bobby-python/bobby-python.theme.bash
+++ b/themes/bobby-python/bobby-python.theme.bash
@@ -1,4 +1,5 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
+
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
 SCM_THEME_PROMPT_PREFIX=" |"
@@ -12,13 +13,13 @@ GIT_THEME_PROMPT_SUFFIX="${green}|"
 CONDAENV_THEME_PROMPT_SUFFIX="|"
 
 function prompt_command() {
-    PS1="\n${yellow}$(python_version_prompt) "  # Name of virtual env followed by python version
-    PS1+="${purple}\h "
-    PS1+="${reset_color}in "
-    PS1+="${green}\w\n"
-    PS1+="${bold_cyan}$(scm_char)"
-    PS1+="${green}$(scm_prompt_info) "
-    PS1+="${green}→${reset_color} "
+	PS1="\n${yellow}$(python_version_prompt) " # Name of virtual env followed by python version
+	PS1+="${purple}\h "
+	PS1+="${reset_color}in "
+	PS1+="${green}\w\n"
+	PS1+="${bold_cyan}$(scm_char)"
+	PS1+="${green}$(scm_prompt_info) "
+	PS1+="${green}→${reset_color} "
 }
 
 safe_append_prompt_command prompt_command
diff --git a/themes/bobby/bobby.theme.bash b/themes/bobby/bobby.theme.bash
index 6470354a..bdf388f7 100644
--- a/themes/bobby/bobby.theme.bash
+++ b/themes/bobby/bobby.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
@@ -14,21 +14,21 @@ RVM_THEME_PROMPT_PREFIX="|"
 RVM_THEME_PROMPT_SUFFIX="|"
 
 __bobby_clock() {
-  printf "$(clock_prompt) "
+	printf '%s' "$(clock_prompt) "
 
-  if [ "${THEME_SHOW_CLOCK_CHAR}" == "true" ]; then
-    printf "$(clock_char) "
-  fi
+	if [ "${THEME_SHOW_CLOCK_CHAR}" == "true" ]; then
+		printf '%s' "$(clock_char) "
+	fi
 }
 
 function prompt_command() {
-    PS1="\n$(battery_char) $(__bobby_clock)"
-    PS1+="${yellow}$(ruby_version_prompt) "
-    PS1+="${purple}\h "
-    PS1+="${reset_color}in "
-    PS1+="${green}\w\n"
-    PS1+="${bold_cyan}$(scm_prompt_char_info) "
-    PS1+="${green}→${reset_color} "
+	PS1="\n$(battery_char) $(__bobby_clock)"
+	PS1+="${yellow}$(ruby_version_prompt) "
+	PS1+="${purple}\h "
+	PS1+="${reset_color}in "
+	PS1+="${green}\w\n"
+	PS1+="${bold_cyan}$(scm_prompt_char_info) "
+	PS1+="${green}→${reset_color} "
 }
 
 THEME_SHOW_CLOCK_CHAR=${THEME_SHOW_CLOCK_CHAR:-"true"}
diff --git a/themes/brainy/brainy.theme.bash b/themes/brainy/brainy.theme.bash
index e27d9d80..db8377ba 100644
--- a/themes/brainy/brainy.theme.bash
+++ b/themes/brainy/brainy.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 # Brainy Bash Prompt for Bash-it
 # by MunifTanjim
@@ -10,7 +10,7 @@
 ____brainy_top_left_parse() {
 	ifs_old="${IFS}"
 	IFS="|"
-	args=( $1 )
+	read -r -a args <<< "$@"
 	IFS="${ifs_old}"
 	if [ -n "${args[3]}" ]; then
 		_TOP_LEFT+="${args[2]}${args[3]}"
@@ -25,7 +25,7 @@ ____brainy_top_left_parse() {
 ____brainy_top_right_parse() {
 	ifs_old="${IFS}"
 	IFS="|"
-	args=( $1 )
+	read -r -a args <<< "$@"
 	IFS="${ifs_old}"
 	_TOP_RIGHT+=" "
 	if [ -n "${args[3]}" ]; then
@@ -35,14 +35,14 @@ ____brainy_top_right_parse() {
 	if [ -n "${args[4]}" ]; then
 		_TOP_RIGHT+="${args[2]}${args[4]}"
 	fi
-	__TOP_RIGHT_LEN=$(( __TOP_RIGHT_LEN + ${#args[1]} + ${#args[3]} + ${#args[4]} + 1 ))
-	(( __SEG_AT_RIGHT += 1 ))
+	__TOP_RIGHT_LEN=$((__TOP_RIGHT_LEN + ${#args[1]} + ${#args[3]} + ${#args[4]} + 1))
+	((__SEG_AT_RIGHT += 1))
 }
 
 ____brainy_bottom_parse() {
 	ifs_old="${IFS}"
 	IFS="|"
-	args=( $1 )
+	read -r -a args <<< "$@"
 	IFS="${ifs_old}"
 	_BOTTOM+="${args[0]}${args[1]}"
 	[ ${#args[1]} -gt 0 ] && _BOTTOM+=" "
@@ -67,7 +67,7 @@ ____brainy_top() {
 		[ -n "${info}" ] && ____brainy_top_right_parse "${info}"
 	done
 
-	[ $__TOP_RIGHT_LEN -gt 0 ] && __TOP_RIGHT_LEN=$(( __TOP_RIGHT_LEN - 1 ))
+	[ $__TOP_RIGHT_LEN -gt 0 ] && __TOP_RIGHT_LEN=$((__TOP_RIGHT_LEN - 1))
 	___cursor_adjust="\033[${__TOP_RIGHT_LEN}D"
 	_TOP_LEFT+="${___cursor_adjust}"
 
@@ -90,7 +90,7 @@ ____brainy_bottom() {
 ___brainy_prompt_user_info() {
 	color=$bold_blue
 	if [ "${THEME_SHOW_SUDO}" == "true" ]; then
-		if sudo -vn 1>/dev/null 2>&1; then
+		if sudo -vn 1> /dev/null 2>&1; then
 			color=$bold_red
 		fi
 	fi
@@ -135,11 +135,11 @@ ___brainy_prompt_ruby() {
 }
 
 ___brainy_prompt_todo() {
-	[ "${THEME_SHOW_TODO}" != "true" ] ||
-	[ -z "$(which todo.sh)" ] && return
+	[ "${THEME_SHOW_TODO}" != "true" ] \
+		|| [ -z "$(which todo.sh)" ] && return
 	color=$bold_white
 	box="[|]"
-	info="t:$(todo.sh ls | egrep "TODO: [0-9]+ of ([0-9]+)" | awk '{ print $4 }' )"
+	info="t:$(todo.sh ls | grep -E "TODO: [0-9]+ of ([0-9]+)" | awk '{ print $4 }')"
 	printf "%s|%s|%s|%s" "${color}" "${info}" "${bold_green}" "${box}"
 }
 
@@ -152,9 +152,9 @@ ___brainy_prompt_clock() {
 }
 
 ___brainy_prompt_battery() {
-	! _command_exists battery_percentage ||
-	[ "${THEME_SHOW_BATTERY}" != "true" ] ||
-	[ "$(battery_percentage)" = "no" ] && return
+	! _command_exists battery_percentage \
+		|| [ "${THEME_SHOW_BATTERY}" != "true" ] \
+		|| [ "$(battery_percentage)" = "no" ] && return
 
 	info=$(battery_percentage)
 	color=$bold_green
@@ -165,8 +165,8 @@ ___brainy_prompt_battery() {
 	fi
 	box="[|]"
 	ac_adapter_connected && charging="+"
-  ac_adapter_disconnected && charging="-"
-  info+=$charging
+	ac_adapter_disconnected && charging="-"
+	info+=$charging
 	[ "$info" == "100+" ] && info="AC"
 	printf "%s|%s|%s|%s" "${color}" "${info}" "${bold_white}" "${box}"
 }
@@ -188,15 +188,15 @@ ___brainy_prompt_char() {
 #########
 
 __brainy_show() {
-  typeset _seg=${1:-}
+	typeset _seg=${1:-}
 	shift
-	export THEME_SHOW_${_seg}=true
+	export "THEME_SHOW_${_seg}"=true
 }
 
 __brainy_hide() {
 	typeset _seg=${1:-}
 	shift
-	export THEME_SHOW_${_seg}=false
+	export "THEME_SHOW_${_seg}"=false
 }
 
 _brainy_completion() {
@@ -207,17 +207,15 @@ _brainy_completion() {
 	actions="show hide"
 	segments="battery clock exitcode python ruby scm sudo todo"
 	case "${_action}" in
-		show)
-			COMPREPLY=( $(compgen -W "${segments}" -- "${cur}") )
-			return 0
-			;;
-		hide)
-			COMPREPLY=( $(compgen -W "${segments}" -- "${cur}") )
+		show | hide)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "${segments}" -- "${cur}"))
 			return 0
 			;;
 	esac
 
-	COMPREPLY=( $(compgen -W "${actions}" -- "${cur}") )
+	# shellcheck disable=SC2207
+	COMPREPLY=($(compgen -W "${actions}" -- "${cur}"))
 	return 0
 }
 
@@ -228,9 +226,11 @@ brainy() {
 	typeset func
 	case $action in
 		show)
-			func=__brainy_show;;
+			func=__brainy_show
+			;;
 		hide)
-			func=__brainy_hide;;
+			func=__brainy_hide
+			;;
 	esac
 	for seg in ${segs}; do
 		seg=$(printf "%s" "${seg}" | tr '[:lower:]' '[:upper:]')
@@ -292,10 +292,10 @@ __brainy_ps2() {
 }
 
 _brainy_prompt() {
-    exitcode="$?"
+	exitcode="$?"
 
-    PS1="$(__brainy_ps1)"
-    PS2="$(__brainy_ps2)"
+	PS1="$(__brainy_ps1)"
+	PS2="$(__brainy_ps2)"
 }
 
 safe_append_prompt_command _brainy_prompt
diff --git a/themes/brunton/brunton.theme.bash b/themes/brunton/brunton.theme.bash
index baa05788..c0bfd49f 100644
--- a/themes/brunton/brunton.theme.bash
+++ b/themes/brunton/brunton.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 SCM_THEME_PROMPT_PREFIX=""
 SCM_THEME_PROMPT_SUFFIX=""
@@ -10,16 +10,14 @@ SCM_SVN_CHAR="${bold_cyan}⑆${normal}"
 SCM_HG_CHAR="${bold_red}☿${normal}"
 
 is_vim_shell() {
-	if [ ! -z "$VIMRUNTIME" ]
-	then
+	if [ -n "$VIMRUNTIME" ]; then
 		echo "[${cyan}vim shell${normal}]"
 	fi
 }
 
 scm_prompt() {
 	CHAR=$(scm_char)
-	if [ $CHAR = $SCM_NONE_CHAR ]
-	then
+	if [ "$CHAR" = "$SCM_NONE_CHAR" ]; then
 		return
 	else
 		echo " $(scm_char) (${white}$(scm_prompt_info)${normal})"
@@ -27,7 +25,7 @@ scm_prompt() {
 }
 
 prompt() {
-  PS1="${white}${background_blue} \u${normal}${background_blue}@${red}${background_blue}\h $(clock_prompt) ${reset_color}${normal} $(battery_charge)\n${bold_black}${background_white} \w ${normal}$(scm_prompt)$(is_vim_shell)\n${white}>${normal} "
+	PS1="${white}${background_blue} \u${normal}${background_blue}@${red}${background_blue}\h $(clock_prompt) ${reset_color}${normal} $(battery_charge)\n${bold_black}${background_white} \w ${normal}$(scm_prompt)$(is_vim_shell)\n${white}>${normal} "
 }
 
 THEME_CLOCK_COLOR=${THEME_CLOCK_COLOR:-"$blue$background_white"}