diff --git a/.editorconfig b/.editorconfig
index e35a1b04e5..8a181ef5e3 100755
--- a/.editorconfig
+++ b/.editorconfig
@@ -13,17 +13,18 @@ insert_final_newline = true
 trim_trailing_whitespace = false
 
 [.git*]
+indent_size = tab
 indent_style = tab
 
 [{**.*sh,test/run}]
+indent_size = tab
 indent_style = tab
-indent_size = 4
 
 shell_variant      = bash
 binary_next_line   = true  # like -bn
 switch_case_indent = true  # like -ci
 space_redirects    = true  # like -sr
-keep_padding       = false  # like -kp
+keep_padding       = false # like -kp
 end_of_line        = lf
 charset            = utf-8
 trim_trailing_whitespace = true
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index dcef30aaa2..f42c096b6c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
   bats-test:
     strategy:
       matrix:
-        os: [ubuntu-20.04, ubuntu-18.04, ubuntu-16.04, macos-10.15]
+        os: [ubuntu-20.04, ubuntu-18.04, macos-10.15, macos-11.0]
 
     runs-on: ${{ matrix.os }}
 
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 6b682bae6a..d976893c05 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -15,11 +15,12 @@ repos:
       - id: mixed-line-ending
       - id: check-added-large-files
   - repo: https://github.com/jumanjihouse/pre-commit-hooks
-    rev: 2.1.4
+    rev: 2.1.5
     hooks:
       - id: git-check  # Configure in .gitattributes
       - id: shellcheck
         exclude: ".bats$"
+        args: [-e, SC1091, -e, SC2034]
       - id: shfmt
         exclude: ".bats$"
   - repo: https://github.com/Lucas-C/pre-commit-hooks
diff --git a/.shellcheckrc b/.shellcheckrc
deleted file mode 100644
index 6418bd8f38..0000000000
--- a/.shellcheckrc
+++ /dev/null
@@ -1,6 +0,0 @@
-# We use colors and not assigned
-disable=SC2154
-# Hard to fix
-disable=SC2155
-# shellcheck is wrong on some
-disable=SC2034
diff --git a/aliases/available/apt.aliases.bash b/aliases/available/apt.aliases.bash
index 2f44493123..b7ef274c81 100644
--- a/aliases/available/apt.aliases.bash
+++ b/aliases/available/apt.aliases.bash
@@ -1,4 +1,4 @@
-#!/bin/bash
+# shellcheck shell=bash
 #
 # -binaryanomaly
 
@@ -8,7 +8,8 @@ about-alias 'Apt and dpkg aliases for Ubuntu and Debian distros.'
 # set apt aliases
 function _set_pkg_aliases()
 {
-	if [ -x $(which apt) ]; then
+	if _command_exists apt
+	then
 		alias apts='apt-cache search'
 		alias aptshow='apt-cache show'
 		alias aptinst='sudo apt-get install -V'
diff --git a/aliases/available/curl.aliases.bash b/aliases/available/curl.aliases.bash
index 3ced1bb54f..a6b2b344ed 100644
--- a/aliases/available/curl.aliases.bash
+++ b/aliases/available/curl.aliases.bash
@@ -6,7 +6,8 @@ about-alias 'Curl aliases for convenience.'
 # set apt aliases
 function _set_pkg_aliases()
 {
-	if [ -x $(which curl) ]; then
+	if _command_exists curl
+	then
 		# follow redirects
                 alias cl='curl -L'
                 # follow redirects, download as original name
diff --git a/aliases/available/general.aliases.bash b/aliases/available/general.aliases.bash
index 0c7bcd9dfd..61ebe538ad 100644
--- a/aliases/available/general.aliases.bash
+++ b/aliases/available/general.aliases.bash
@@ -30,7 +30,7 @@ then
   alias grep='grep --color=auto'
 fi
 
-if which gshuf &> /dev/null
+if _command_exists gshuf
 then
   alias shuf=gshuf
 fi
@@ -65,7 +65,7 @@ alias -- -='cd -'        # Go back
 alias h='history'
 
 # Tree
-if [ ! -x "$(which tree 2>/dev/null)" ]
+if ! _command_exists tree
 then
   alias tree="find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g'"
 fi
diff --git a/aliases/available/git.aliases.bash b/aliases/available/git.aliases.bash
index 478861ba2d..8cafa82b01 100644
--- a/aliases/available/git.aliases.bash
+++ b/aliases/available/git.aliases.bash
@@ -37,8 +37,8 @@ alias gcb='git checkout -b'
 alias gco='git checkout'
 alias gcob='git checkout -b'
 alias gcobu='git checkout -b ${USER}/'
-alias gcom='git checkout master'
-alias gcpd='git checkout master; git pull; git branch -D'
+alias gcom='git checkout $(get_default_branch)'
+alias gcpd='git checkout $(get_default_branch); git pull; git branch -D'
 alias gct='git checkout --track'
 
 # clone
@@ -64,13 +64,14 @@ alias gf='git fetch --all --prune'
 alias gft='git fetch --all --prune --tags'
 alias gftv='git fetch --all --prune --tags --verbose'
 alias gfv='git fetch --all --prune --verbose'
-alias gmu='git fetch origin -v; git fetch upstream -v; git merge upstream/master'
+alias gmu='git fetch origin -v; git fetch upstream -v; git merge upstream/$(get_default_branch)'
 alias gup='git fetch && git rebase'
 
 # log
 alias gg='git log --graph --pretty=format:'\''%C(bold)%h%Creset%C(magenta)%d%Creset %s %C(yellow)<%an> %C(cyan)(%cr)%Creset'\'' --abbrev-commit --date=relative'
 alias ggf='git log --graph --date=short --pretty=format:'\''%C(auto)%h %Cgreen%an%Creset %Cblue%cd%Creset %C(auto)%d %s'\'''
 alias ggs='gg --stat'
+alias ggup='git log --branches --not --remotes --no-walk --decorate --oneline' # FROM https://stackoverflow.com/questions/39220870/in-git-list-names-of-branches-with-unpushed-commits
 alias gll='git log --graph --pretty=oneline --abbrev-commit'
 alias gnew='git log HEAD@{1}..HEAD@{0}' # Show commits since last pull, see http://blogs.atlassian.com/2014/10/advanced-git-aliases/
 alias gwc='git whatchanged'
@@ -104,7 +105,7 @@ alias gp='git push'
 alias gpd='git push --delete'
 alias gpf='git push --force'
 alias gpo='git push origin HEAD'
-alias gpom='git push origin master'
+alias gpom='git push origin $(get_default_branch)'
 alias gpu='git push --set-upstream'
 alias gpunch='git push --force-with-lease'
 alias gpuo='git push --set-upstream origin'
@@ -112,7 +113,7 @@ alias gpuoc='git push --set-upstream origin $(git symbolic-ref --short HEAD)'
 
 # pull
 alias gl='git pull'
-alias glum='git pull upstream master'
+alias glum='git pull upstream $(get_default_branch)'
 alias gpl='git pull'
 alias gpp='git pull && git push'
 alias gpr='git pull --rebase'
@@ -128,9 +129,9 @@ alias grm='git rm'
 # rebase
 alias grb='git rebase'
 alias grbc='git rebase --continue'
-alias grm='git rebase master'
-alias grmi='git rebase master -i'
-alias gprom='git fetch origin master && git rebase origin/master && git update-ref refs/heads/master origin/master' # Rebase with latest remote master
+alias grm='git rebase $(get_default_branch)'
+alias grmi='git rebase $(get_default_branch) -i'
+alias gprom='git fetch origin $(get_default_branch) && git rebase origin/$(get_default_branch) && git update-ref refs/heads/$(get_default_branch) origin/$(get_default_branch)' # Rebase with latest remote
 
 # reset
 alias gus='git reset HEAD'
@@ -174,7 +175,7 @@ alias gsu='git submodule update --init --recursive'
 # these aliases requires git v2.23+
 alias gsw='git switch'
 alias gswc='git switch --create'
-alias gswm='git switch master'
+alias gswm='git switch $(get_default_branch)'
 alias gswt='git switch --track'
 
 # tag
@@ -196,3 +197,11 @@ esac
 function gdv() {
 	git diff --ignore-all-space "$@" | vim -R -
 }
+
+function get_default_branch() {
+	if git branch | grep -q main; then
+		echo main
+	else
+		echo master
+	fi
+}
diff --git a/aliases/available/vim.aliases.bash b/aliases/available/vim.aliases.bash
index d19057d0b3..b426d27004 100644
--- a/aliases/available/vim.aliases.bash
+++ b/aliases/available/vim.aliases.bash
@@ -2,24 +2,14 @@
 cite 'about-alias'
 about-alias 'vim abbreviations'
 
-VIM=$(command -v vim)
-GVIM=$(command -v gvim)
-MVIM=$(command -v mvim)
+_command_exists vim || return
 
-if [[ -n $VIM ]]; then
-	alias v='$VIM'
-	# open the vim help in fullscreen incorporated from
-	# https://stackoverflow.com/a/4687513
-	alias vimh='${VIM} -c ":h | only"'
-fi
+alias v='vim'
+# open the vim help in fullscreen incorporated from
+# https://stackoverflow.com/a/4687513
+alias vimh='vim -c ":h | only"'
 
 # open vim in new tab is taken from
 # http://stackoverflow.com/questions/936501/let-gvim-always-run-a-single-instancek
-case $OSTYPE in
-	darwin*)
-		[[ -n $MVIM ]] && function mvimt { command mvim --remote-tab-silent "$@" || command mvim "$@"; }
-		;;
-	*)
-		[[ -n $GVIM ]] && function gvimt { command gvim --remote-tab-silent "$@" || command gvim "$@"; }
-		;;
-esac
+_command_exists mvim && function mvimt { command mvim --remote-tab-silent "$@" || command mvim "$@"; }
+_command_exists gvim && function gvimt { command gvim --remote-tab-silent "$@" || command gvim "$@"; }
diff --git a/bash_it.sh b/bash_it.sh
index cb50420291..215c33c7db 100755
--- a/bash_it.sh
+++ b/bash_it.sh
@@ -3,7 +3,7 @@
 BASH_IT_LOG_PREFIX="core: main: "
 
 # Only set $BASH_IT if it's not already set
-if [ -z "$BASH_IT" ]; then
+if [ -z "${BASH_IT:-}" ]; then
 	# Setting $BASH to maintain backwards compatibility
 	export BASH_IT=$BASH
 	BASH="$(bash -c 'echo $BASH')"
@@ -20,12 +20,12 @@ source "${BASH_IT}"/vendor/github.com/erichs/composure/composure.sh
 source "${BASH_IT}/lib/log.bash"
 
 # We can only log it now
-[ -z "$BASH_IT_OLD_BASH_SETUP" ] || _log_warning "BASH_IT variable not initialized, please upgrade your bash-it version and reinstall it!"
+[ -z "${BASH_IT_OLD_BASH_SETUP:-}" ] || _log_warning "BASH_IT variable not initialized, please upgrade your bash-it version and reinstall it!"
 
 # For backwards compatibility, look in old BASH_THEME location
-if [ -z "$BASH_IT_THEME" ]; then
+if [ -z "${BASH_IT_THEME:-}" ]; then
 	_log_warning "BASH_IT_THEME variable not initialized, please upgrade your bash-it version and reinstall it!"
-	export BASH_IT_THEME="$BASH_THEME"
+	export BASH_IT_THEME="${BASH_THEME:-}"
 	unset BASH_THEME
 fi
 
@@ -114,6 +114,7 @@ for _bash_it_config_file in $CUSTOM; do
 	if [ -e "${_bash_it_config_file}" ]; then
 		filename=$(basename "${_bash_it_config_file}")
 		filename=${filename%*.bash}
+		# shellcheck disable=SC2034
 		BASH_IT_LOG_PREFIX="custom: $filename: "
 		_log_debug "Loading custom file..."
 		# shellcheck disable=SC1090
@@ -122,7 +123,7 @@ for _bash_it_config_file in $CUSTOM; do
 done
 
 unset _bash_it_config_file
-if [[ $PROMPT ]]; then
+if [[ -n "${PROMPT:-}" ]]; then
 	export PS1="\[""$PROMPT""\]"
 fi
 
@@ -144,7 +145,7 @@ if [ -e "$HOME/.jekyllconfig" ]; then
 fi
 
 # BASH_IT_RELOAD_LEGACY is set.
-if ! command -v reload &> /dev/null && [ -n "$BASH_IT_RELOAD_LEGACY" ]; then
+if ! _command_exists reload && [[ -n "${BASH_IT_RELOAD_LEGACY:-}" ]]; then
 	case $OSTYPE in
 		darwin*)
 			alias reload='source ~/.bash_profile'
diff --git a/clean_files.txt b/clean_files.txt
index edbe1df405..75aca06e5c 100644
--- a/clean_files.txt
+++ b/clean_files.txt
@@ -42,12 +42,14 @@ completion/available/cargo.completion.bash
 completion/available/composer.completion.bash
 completion/available/conda.completion.bash
 completion/available/consul.completion.bash
+completion/available/dart.completion.bash
 completion/available/django.completion.bash
 completion/available/dmidecode.completion.bash
 completion/available/docker-machine.completion.bash
 completion/available/docker.completion.bash
 completion/available/gcloud.completion.bash
 completion/available/gem.completion.bash
+completion/available/git.completion.bash
 completion/available/github-cli.completion.bash
 completion/available/go.completion.bash
 completion/available/helm.completion.bash
@@ -57,6 +59,7 @@ completion/available/jungle.completion.bash
 completion/available/knife.completion.bash
 completion/available/kontena.completion.bash
 completion/available/kubectl.completion.bash
+completion/available/laravel.completion.bash
 completion/available/lerna.completion.bash
 completion/available/minikube.completion.bash
 completion/available/ngrok.completion.bash
@@ -71,12 +74,20 @@ completion/available/rustup.completion.bash
 completion/available/sdkman.completion.bash
 completion/available/vault.completion.bash
 completion/available/vuejs.completion.bash
+completion/available/wpscan.completion.bash
+
+# libraries
+lib/utilities.bash
 
 # plugins
 #
 plugins/available/alias-completion.plugin.bash
+plugins/available/autojump.plugin.bash
+plugins/available/base.plugin.bash
 plugins/available/basher.plugin.bash
+plugins/available/blesh.plugin.bash
 plugins/available/cmd-returned-notify.plugin.bash
+plugins/available/direnv.plugin.bash
 plugins/available/docker-machine.plugin.bash
 plugins/available/git.plugin.bash
 plugins/available/go.plugin.bash
@@ -84,6 +95,17 @@ plugins/available/goenv.plugin.bash
 plugins/available/history-search.plugin.bash
 plugins/available/history-substring-search.plugin.bash
 plugins/available/history.plugin.bash
+plugins/available/hub.plugin.bash
+plugins/available/jump.plugin.bash
+plugins/available/less-pretty-cat.plugin.bash
+plugins/available/node.plugin.bash
+plugins/available/nodenv.plugin.bash
+plugins/available/percol.plugin.bash
+plugins/available/plenv.plugin.bash
+plugins/available/pyenv.plugin.bash
+plugins/available/rbenv.plugin.bash
+plugins/available/ruby.plugin.bash
+plugins/available/textmate.plugin.bash
 plugins/available/thefuck.plugin.bash
 plugins/available/xterm.plugin.bash
 
@@ -115,6 +137,7 @@ themes/powerline
 themes/powerline-multiline
 themes/powerline-naked
 themes/powerline-plain
+themes/pure
 themes/purity
 
 # vendor init files
diff --git a/completion/available/awscli.completion.bash b/completion/available/awscli.completion.bash
index 530bdd2739..a30418373a 100644
--- a/completion/available/awscli.completion.bash
+++ b/completion/available/awscli.completion.bash
@@ -1 +1,6 @@
-[[ -x "$(which aws_completer)" ]] && complete -C "$(which aws_completer)" aws
+# shellcheck shell=bash
+
+if _command_exists aws_completer
+then
+	complete -C "$(command -v aws_completer)" aws
+fi
diff --git a/completion/available/brew.completion.bash b/completion/available/brew.completion.bash
index 91c288def4..61998f8a71 100644
--- a/completion/available/brew.completion.bash
+++ b/completion/available/brew.completion.bash
@@ -5,28 +5,26 @@ about-completion "brew completion"
 # Load late to make sure `system` completion loads first
 # BASH_IT_LOAD_PRIORITY: 375
 
-if [[ "$(uname -s)" != 'Darwin' ]]; then
+if [[ "$OSTYPE" != 'darwin'* ]]; then
 	_log_warning "unsupported operating system - only 'Darwin' is supported"
 	return 0
 fi
 
 # Make sure brew is installed
-_command_exists brew || return 0
+_bash_it_homebrew_check || return 0
 
-BREW_PREFIX=${BREW_PREFIX:-$(brew --prefix)}
-
-if [[ -r "$BREW_PREFIX"/etc/bash_completion.d/brew ]]; then
+if [[ -r "$BASH_IT_HOMEBREW_PREFIX/etc/bash_completion.d/brew" ]]; then
 	# shellcheck disable=1090
-	source "$BREW_PREFIX"/etc/bash_completion.d/brew
+	source "$BASH_IT_HOMEBREW_PREFIX/etc/bash_completion.d/brew"
 
-elif [[ -r "$BREW_PREFIX"/Library/Contributions/brew_bash_completion.sh ]]; then
+elif [[ -r "$BASH_IT_HOMEBREW_PREFIX/Library/Contributions/brew_bash_completion.sh" ]]; then
 	# shellcheck disable=1090
-	source "$BREW_PREFIX"/Library/Contributions/brew_bash_completion.sh
+	source "$BASH_IT_HOMEBREW_PREFIX/Library/Contributions/brew_bash_completion.sh"
 
-elif [[ -f "$BREW_PREFIX"/completions/bash/brew ]]; then
+elif [[ -f "$BASH_IT_HOMEBREW_PREFIX/completions/bash/brew" ]]; then
 	# For the git-clone based installation, see here for more info:
 	# https://github.com/Bash-it/bash-it/issues/1458
 	# https://docs.brew.sh/Shell-Completion
 	# shellcheck disable=1090
-	source "$BREW_PREFIX"/completions/bash/brew
+	source "$BASH_IT_HOMEBREW_PREFIX/completions/bash/brew"
 fi
diff --git a/completion/available/composer.completion.bash b/completion/available/composer.completion.bash
index eefe50fa34..176f08328d 100644
--- a/completion/available/composer.completion.bash
+++ b/completion/available/composer.completion.bash
@@ -3,14 +3,14 @@ cite "about-completion"
 about-completion "composer completion"
 
 function __composer_completion() {
-	local cur coms opts com
+	local cur coms opts com words
 	COMPREPLY=()
 	_get_comp_words_by_ref -n : cur words
 
 	# lookup for command
 	for word in "${words[@]:1}"; do
-		if [[ $word != -* ]]; then
-			com=$word
+		if [[ "${word}" != -* ]]; then
+			com="${word}"
 			break
 		fi
 	done
@@ -19,7 +19,7 @@ function __composer_completion() {
 	if [[ ${cur} == --* ]]; then
 		opts="--help --quiet --verbose --version --ansi --no-ansi --no-interaction --profile --no-plugins --working-dir"
 
-		case "$com" in
+		case "${com}" in
 			about)
 				opts="${opts} "
 				;;
@@ -109,18 +109,18 @@ function __composer_completion() {
 
 		# shellcheck disable=SC2207
 		COMPREPLY=($(compgen -W "${opts}" -- "${cur}"))
-		__ltrim_colon_completions "$cur"
+		__ltrim_colon_completions "${cur}"
 
 		return 0
 	fi
 
 	# completing for a command
-	if [[ "$cur" == "$com" ]]; then
+	if [[ "${cur}" == "${com}" ]]; then
 		coms="about archive browse clear-cache config create-project depends diagnose dump-autoload exec global help init install licenses list outdated prohibits remove require run-script search self-update show status suggests update validate"
 
 		# shellcheck disable=SC2207
 		COMPREPLY=($(compgen -W "${coms}" -- "${cur}"))
-		__ltrim_colon_completions "$cur"
+		__ltrim_colon_completions "${cur}"
 
 		return 0
 	fi
diff --git a/completion/available/consul.completion.bash b/completion/available/consul.completion.bash
index 3697ffc5bf..511cf37209 100644
--- a/completion/available/consul.completion.bash
+++ b/completion/available/consul.completion.bash
@@ -3,5 +3,5 @@ cite "about-completion"
 about-completion "Hashicorp consul completion"
 
 if _command_exists consul; then
-	complete -C "$(which consul)" consul
+	complete -C "$(command -v consul)" consul
 fi
diff --git a/completion/available/dart.completion.bash b/completion/available/dart.completion.bash
new file mode 100644
index 0000000000..b7563443cf
--- /dev/null
+++ b/completion/available/dart.completion.bash
@@ -0,0 +1,48 @@
+# shellcheck shell=bash
+
+__dart_completion() {
+	# shellcheck disable=SC2155
+	local prev=$(_get_pword)
+	# shellcheck disable=SC2155
+	local curr=$(_get_cword)
+
+	local HELP="--help -h"
+	local VERBOSE="-v --verbose"
+
+	case $prev in
+		analyze)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP --fatal-infos --no-fatal-warnings --fatal-warnings" -- "$curr"))
+			;;
+		compile)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP aot-snapshot exe js jit-snapshot kernel" -- "$curr"))
+			;;
+		create)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP --template -t --no-pub --pub --force" -- "$curr"))
+			;;
+		-t | --template)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "console-simple console-full package-simple web-simple" -- "$curr"))
+			;;
+		format)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP $VERBOSE -o --output --fix -l --line-length" -- "$curr"))
+			;;
+		pub)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP $VERBOSE --version --no-trace --trace --verbosity cache deps downgrade get global logout outdated publish run upgrade uploader version" -- "$curr"))
+			;;
+		run)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP --observe --enable-vm-service --no-pause-isolates-on-exit --no-pause-isolates-on-unhandled-exceptions --no-warn-on-pause-with-no-debugger --pause-isolates-on-exit --pause-isolates-on-unhandled-exceptions --warn-on-pause-with-no-debugger" -- "$curr"))
+			;;
+		dart)
+			# shellcheck disable=SC2207
+			COMPREPLY=($(compgen -W "$HELP $VERBOSE --version --enable-analytics --disable-analytics help analyze compile create format pub run test" -- "$curr"))
+			;;
+	esac
+}
+
+complete -F __dart_completion dart
diff --git a/completion/available/defaults.completion.bash b/completion/available/defaults.completion.bash
index 5a8d0340d3..c43c0aae49 100644
--- a/completion/available/defaults.completion.bash
+++ b/completion/available/defaults.completion.bash
@@ -13,7 +13,7 @@ _defaults_domains()
     COMPREPLY=()
     cur=${COMP_WORDS[COMP_CWORD]}
 
-	local domains=$( defaults domains | sed -e 's/, /:/g' | tr : '\n' | sed -e 's/ /\\ /g' | grep -i "^$cur" )
+	local domains=$( defaults domains | sed -e 's/, /:/g' | tr : '\n' | sed -e 's/ /\\ /g' | grep "^$cur" )
 	local IFS=$'\n'
 	COMPREPLY=( $domains )
 	if [[ $( echo '-app' | grep "^$cur" ) ]]; then
@@ -41,8 +41,8 @@ _defaults()
 			COMPREPLY=( $( compgen -W "$cmds" -- $cur ) )
 			return 0
 		elif [[ "$prev" == "-host" ]]; then
-			return 0
 			_known_hosts -a
+			return 0
 		else
 			_defaults_domains
 			return 0
diff --git a/completion/available/dmidecode.completion.bash b/completion/available/dmidecode.completion.bash
index fc50c1f078..4a8845244e 100644
--- a/completion/available/dmidecode.completion.bash
+++ b/completion/available/dmidecode.completion.bash
@@ -1,7 +1,9 @@
 # shellcheck shell=bash
 
 function __dmidecode_completion() {
+	# shellcheck disable=SC2155
 	local prev=$(_get_pword)
+	# shellcheck disable=SC2155
 	local curr=$(_get_cword)
 
 	case $prev in
diff --git a/completion/available/docker-compose.completion.bash b/completion/available/docker-compose.completion.bash
old mode 100644
new mode 100755
index bf2c13fb41..1102f5d97e
--- a/completion/available/docker-compose.completion.bash
+++ b/completion/available/docker-compose.completion.bash
@@ -676,7 +676,7 @@ _docker_compose() {
 	done
 
 	local completions_func=_docker_compose_${command//-/_}
-	declare -F $completions_func >/dev/null && $completions_func
+	_is_function $completions_func && $completions_func
 
 	eval "$previous_extglob_setting"
 	return 0
diff --git a/completion/available/fabric.completion.bash b/completion/available/fabric.completion.bash
index 7809b38014..6f746454dc 100644
--- a/completion/available/fabric.completion.bash
+++ b/completion/available/fabric.completion.bash
@@ -41,8 +41,8 @@ export FAB_COMPLETION_CACHED_TASKS_FILENAME=".fab_tasks~"
 
 
 # Set command to get time of last file modification as seconds since Epoch
-case `uname` in
-    Darwin|FreeBSD)
+case "$OSTYPE" in
+    'darwin'*|'freebsd'*)
         __FAB_COMPLETION_MTIME_COMMAND="stat -f '%m'"
         ;;
     *)
diff --git a/completion/available/git.completion.bash b/completion/available/git.completion.bash
index 0020ad1b9f..31b77fa3de 100644
--- a/completion/available/git.completion.bash
+++ b/completion/available/git.completion.bash
@@ -1,39 +1,42 @@
-#!/usr/bin/env bash
-
-# Only operate on MacOS since there are no linux paths
-if [[ "$(uname -s)" != 'Darwin' ]] ; then
-  _log_warning "unsupported operating system - only 'Darwin' is supported"
-  return 0
-fi
+# shellcheck shell=bash
+#
+# Locate and load completions for `git`.
 
 # Make sure git is installed
-_command_exists git || return 0
+_command_exists git || return
 
 # Don't handle completion if it's already managed
-if complete -p git &>/dev/null ; then
-  _log_warning "completion already loaded - this usually means it is safe to stop using this completion"
-  return 0
+if complete -p git &> /dev/null; then
+	_log_warning "completion already loaded - this usually means it is safe to stop using this completion"
+	return 0
 fi
 
-_git_bash_completion_found=false
+_git_bash_completion_xcrun_git=
+if _command_exists xcrun; then
+	_git_bash_completion_xcrun_git="$(xcrun --find git)"
+fi
 _git_bash_completion_paths=(
-  # MacOS non-system locations
-  '/Library/Developer/CommandLineTools/usr/share/git-core/git-completion.bash'
-  '/Applications/Xcode.app/Contents/Developer/usr/share/git-core/git-completion.bash'
+	# Standard locations
+	"${GIT_EXE%/*}/../share/git-core/git-completion.bash"
+	"${GIT_EXE%/*}/../share/git-core/contrib/completion/git-completion.bash"
+	"${GIT_EXE%/*}/../etc/bash_completion.d/git-completion.bash"
+	# MacOS non-system locations
+	"${_git_bash_completion_xcrun_git%/bin/git}/share/git-core/git-completion.bash"
 )
 
 # Load the first completion file found
-for _comp_path in "${_git_bash_completion_paths[@]}" ; do
-  if [ -r "$_comp_path" ] ; then
-    _git_bash_completion_found=true
-    source "$_comp_path"
-    break
-  fi
+_git_bash_completion_found=false
+for _comp_path in "${_git_bash_completion_paths[@]}"; do
+	if [[ -r "$_comp_path" ]]; then
+		_git_bash_completion_found=true
+		# shellcheck disable=SC1090 # don't follow
+		source "$_comp_path"
+		break
+	fi
 done
 
 # Cleanup
 if [[ "${_git_bash_completion_found}" == false ]]; then
-  _log_warning "no completion files found - please try enabling the 'system' completion instead."
+	_log_warning "no completion files found - please try enabling the 'system' completion instead."
 fi
-unset _git_bash_completion_paths
-unset _git_bash_completion_found
+unset "${!_git_bash_completion@}"
diff --git a/completion/available/git_flow.completion.bash b/completion/available/git_flow.completion.bash
index 04f20ccd54..7bfc9ef42c 100644
--- a/completion/available/git_flow.completion.bash
+++ b/completion/available/git_flow.completion.bash
@@ -172,6 +172,7 @@ __git_flow_list_hotfixes ()
 }
 
 # temporarily wrap __git_find_on_cmdline() for backwards compatibility
-if [ -z "`type -t __git_find_subcommand`" ]; then
+if ! _command_exists __git_find_subcommand
+then
 	alias __git_find_subcommand=__git_find_on_cmdline
 fi
diff --git a/completion/available/git_flow_avh.completion.bash b/completion/available/git_flow_avh.completion.bash
index 0b73a0bedd..abb51bf806 100644
--- a/completion/available/git_flow_avh.completion.bash
+++ b/completion/available/git_flow_avh.completion.bash
@@ -505,6 +505,7 @@ __git_flow_list_branches ()
 }
 
 # alias __git_find_on_cmdline for backwards compatibility
-if [ -z "`type -t __git_find_on_cmdline`" ]; then
+if ! _command_exists __git_find_on_cmdline
+then
 	alias __git_find_on_cmdline=__git_find_subcommand
 fi
diff --git a/completion/available/gradle.completion.bash b/completion/available/gradle.completion.bash
index 2b33383ff4..35971d5075 100644
--- a/completion/available/gradle.completion.bash
+++ b/completion/available/gradle.completion.bash
@@ -22,17 +22,9 @@
 # Avoid inaccurate completions for subproject tasks
 COMP_WORDBREAKS=$(echo "$COMP_WORDBREAKS" | sed -e 's/://g')
 
-__gradle-set-project-root-dir() {
-    local dir=`pwd`
-    project_root_dir=`pwd`
-    while [[ $dir != '/' ]]; do
-        if [[ -f "$dir/settings.gradle" || -f "$dir/gradlew" ]]; then
-            project_root_dir=$dir
-            return 0
-        fi
-        dir="$(dirname "$dir")"
-    done
-    return 1
+function __gradle-set-project-root-dir() {
+    project_root_dir="$(_bash-it-find-in-ancestor "settings.gradle" "gradlew")"
+    return "$?"
 }
 
 __gradle-init-cache-dir() {
@@ -58,9 +50,9 @@ __gradle-set-cache-name() {
 
 __gradle-set-files-checksum() {
     # Cache MD5 sum of all Gradle scripts and modified timestamps
-    if builtin command -v md5 > /dev/null; then
+    if _command_exists md5; then
         gradle_files_checksum=$(md5 -q -s "$(cat "$cache_dir/$cache_name" | xargs ls -o 2>/dev/null)")
-    elif builtin command -v md5sum > /dev/null; then
+    elif _command_exists md5sum; then
         gradle_files_checksum=$(cat "$cache_dir/$cache_name" | xargs ls -o 2>/dev/null | md5sum | awk '{print $1}')
     else
         echo "Cannot generate completions as neither md5 nor md5sum exist on \$PATH"
diff --git a/completion/available/hub.completion.bash b/completion/available/hub.completion.bash
index 79d76bf0e1..67a5e29b1a 100644
--- a/completion/available/hub.completion.bash
+++ b/completion/available/hub.completion.bash
@@ -23,12 +23,12 @@
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 # If there is no git tab completion, but we have the _completion loader try to load it
-if ! declare -F _git > /dev/null && declare -F _completion_loader > /dev/null; then
+if ! _is_function _git && _is_function _completion_loader; then
   _completion_loader git
 fi
 
 # Check that git tab completion is available and we haven't already set up completion
-if declare -F _git > /dev/null && ! declare -F __git_list_all_commands_without_hub > /dev/null; then
+if _is_function _git && ! _is_function __git_list_all_commands_without_hub; then
   # Duplicate and rename the 'list_all_commands' function
   eval "$(declare -f __git_list_all_commands | \
         sed 's/__git_list_all_commands/__git_list_all_commands_without_hub/')"
@@ -227,7 +227,7 @@ EOF
       ((c++))
     done
     if [ -z "$name" ]; then
-      repo=$(basename "$(pwd)")
+      repo="$(basename "${PWD}")"
     fi
     case "$prev" in
       -d|-h)
diff --git a/completion/available/knife.completion.bash b/completion/available/knife.completion.bash
index 83b332f9fd..4b9950edef 100644
--- a/completion/available/knife.completion.bash
+++ b/completion/available/knife.completion.bash
@@ -42,6 +42,7 @@ _KAC_is_file_newer_than() {
 _KAC_regen_cache() {
 	local CACHE_NAME=$1
 	local CACHE_PATH="$_KNIFE_AUTOCOMPLETE_CACHE_DIR/$CACHE_NAME"
+	# shellcheck disable=SC2155
 	local TMP_FILE=$(mktemp "$_KAC_CACHE_TMP_DIR/$CACHE_NAME.XXXX")
 	shift 1
 	# discard the temp file if it's empty AND the previous command didn't exit successfully, but still mark the cache as updated
@@ -66,6 +67,7 @@ _KAC_get_command_from_cache_name() {
 # otherwise it waits for the cache to be generated
 # in either case, it regenerates the cache, and sets the _KAC_CACHE_PATH env variable
 # for obvious reason, do NOT call that in a sub-shell (in particular, no piping)
+# shellcheck disable=SC2155
 _KAC_get_and_regen_cache() {
 	# the cache name can't have space in it
 	local CACHE_NAME=$(_KAC_get_cache_name_from_command "$@")
@@ -100,7 +102,7 @@ _KAC_clean_cache() {
 
 # perform a cache cleaning when loading this file
 # On big systems this could baloon up to a 30 second run or more, so not enabling by default.
-[[ "${KNIFE_CACHE_CLEAN}" ]] && _KAC_clean_cache
+[[ -n "${KNIFE_CACHE_CLEAN}" ]] && _KAC_clean_cache
 
 #####################################
 ### End of cache helper functions ###
@@ -118,7 +120,7 @@ _KAC_get_current_base_command() {
 	local PREVIOUS="knife"
 	local I=1
 	local CURRENT
-	while [ $I -le "$COMP_CWORD" ]; do
+	while [[ "${I}" -le "${COMP_CWORD}" ]]; do
 		# command words are all lower-case
 		echo "${COMP_WORDS[$I]}" | grep -E "^[a-z]+$" > /dev/null || break
 		CURRENT="$PREVIOUS ${COMP_WORDS[$I]}"
@@ -127,12 +129,13 @@ _KAC_get_current_base_command() {
 		I=$((I + 1))
 	done
 	_KAC_CURRENT_COMMAND=$PREVIOUS
-	[ $I -le "$COMP_CWORD" ] && _KAC_CURRENT_COMMAND_NB_WORDS=$I
+	[[ "${I}" -le "${COMP_CWORD}" ]] && _KAC_CURRENT_COMMAND_NB_WORDS="${I}"
 }
 
 # searches the position of the currently completed argument in the current base command
 # (i.e. handles "plural" arguments such as knife cookbook upload cookbook1 cookbook2 and so on...)
 # assumes the current base command is complete
+# shellcheck disable=SC2155
 _KAC_get_current_arg_position() {
 	local CURRENT_ARG_POS=$((_KAC_CURRENT_COMMAND_NB_WORDS + 1))
 	local COMPLETE_COMMAND=$(grep -E "^$_KAC_CURRENT_COMMAND" "$_KAC_CACHE_PATH")
@@ -150,10 +153,11 @@ _KAC_get_current_arg_position() {
 _knife() {
 	_KAC_get_and_regen_cache _KAC_knife_commands
 	local RAW_LIST ITEM REGEN_CMD ARG_POSITION
+	# shellcheck disable=SC2034
 	COMREPLY=()
 	# get correct command & arg pos
 	_KAC_get_current_base_command && ARG_POSITION=$(_KAC_get_current_arg_position) || ARG_POSITION=$((COMP_CWORD + 1))
-	RAW_LIST=$(grep -E "^$_KAC_CURRENT_COMMAND" "$_KAC_CACHE_PATH" | cut -d ' ' -f $ARG_POSITION | uniq)
+	RAW_LIST=$(grep -E "^${_KAC_CURRENT_COMMAND}" "${_KAC_CACHE_PATH}" | cut -d ' ' -f "${ARG_POSITION}" | uniq)
 
 	# we need to process that raw list a bit, most notably for placeholders
 	# NOTE: I chose to explicitely fetch & cache _certain_ informations for the server (cookbooks & node names, etc)
diff --git a/completion/available/laravel.completion.bash b/completion/available/laravel.completion.bash
index 7bd6f22323..8f03256896 100644
--- a/completion/available/laravel.completion.bash
+++ b/completion/available/laravel.completion.bash
@@ -1,15 +1,16 @@
-#!/usr/bin/bash
+# shellcheck shell=bash
 
-if command -v laravel > /dev/null; then
-    __laravel_completion()  {
-        local OPTS=("-h --help -q --quiet --ansi --no-ansi -n --no-interaction -v -vv -vvv --verbose help list new")
-        COMPREPLY=()
-        for _opt_ in ${OPTS[@]}; do
-            if [[ "$_opt_" == "$2"* ]]; then
-                COMPREPLY+=("$_opt_")
-            fi
-        done
-    }
+_command_exists laravel || return
 
-    complete -F __laravel_completion laravel
-fi
+function __laravel_completion() {
+	local OPTS=('-h' '--help' '-q' '--quiet' '--ansi' '--no-ansi' '-n' '--no-interaction' '-v' '-vv' '-vvv' '--verbose' 'help' 'list' 'new')
+	local _opt_
+	COMPREPLY=()
+	for _opt_ in "${OPTS[@]}"; do
+		if [[ "$_opt_" == "$2"* ]]; then
+			COMPREPLY+=("$_opt_")
+		fi
+	done
+}
+
+complete -F __laravel_completion laravel
diff --git a/completion/available/ngrok.completion.bash b/completion/available/ngrok.completion.bash
index ffbdd3c870..ca50a16f42 100644
--- a/completion/available/ngrok.completion.bash
+++ b/completion/available/ngrok.completion.bash
@@ -1,7 +1,9 @@
 # shellcheck shell=bash
 
 __ngrok_completion() {
+	# shellcheck disable=SC2155
 	local prev=$(_get_pword)
+	# shellcheck disable=SC2155
 	local curr=$(_get_cword)
 
 	local BASE_NO_CONF="--log --log-format --log-level --help"
diff --git a/completion/available/notify-send.completion.bash b/completion/available/notify-send.completion.bash
index b2c171e90f..676485f83a 100644
--- a/completion/available/notify-send.completion.bash
+++ b/completion/available/notify-send.completion.bash
@@ -1,7 +1,9 @@
 # shellcheck shell=bash
 
 function __notify-send_completions() {
+	# shellcheck disable=SC2155
 	local curr=$(_get_cword)
+	# shellcheck disable=SC2155
 	local prev=$(_get_pword)
 
 	case $prev in
diff --git a/completion/available/pew.completion.bash b/completion/available/pew.completion.bash
index 73d62e395a..04e67ecbf5 100644
--- a/completion/available/pew.completion.bash
+++ b/completion/available/pew.completion.bash
@@ -1 +1,6 @@
-[[ -x "$(which pew)" ]] && source "$(pew shell_config)"
+# shellcheck shell=bash
+
+if _command_exists pew
+then
+	source "$(pew shell_config)"
+fi
diff --git a/completion/available/pip.completion.bash b/completion/available/pip.completion.bash
index 7ed8c17ee3..f094d6edec 100644
--- a/completion/available/pip.completion.bash
+++ b/completion/available/pip.completion.bash
@@ -6,6 +6,15 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initialize the corresponding environment.
 # So that pip is in the system's path.
-if _command_exists pip; then
-	eval "$(pip completion --bash)"
-fi
+_command_exists pip || return
+
+function __bash_it_complete_pip() {
+	if _command_exists _pip_completion; then
+		complete -o default -F _pip_completion pip
+		_pip_completion "$@"
+	else
+		eval "$(pip completion --bash)"
+		_pip_completion "$@"
+	fi
+}
+complete -o default -F __bash_it_complete_pip pip
diff --git a/completion/available/pip3.completion.bash b/completion/available/pip3.completion.bash
index c2b585648e..34abc053fe 100644
--- a/completion/available/pip3.completion.bash
+++ b/completion/available/pip3.completion.bash
@@ -6,6 +6,15 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initialize the corresponding environment.
 # So that pip3 is in the system's path.
-if _command_exists pip3; then
-	eval "$(pip3 completion --bash)"
-fi
+_command_exists pip3 || return
+
+function __bash_it_complete_pip3() {
+	if _command_exists _pip_completion; then
+		complete -o default -F _pip_completion pip3
+		_pip_completion "$@"
+	else
+		eval "$(pip3 completion --bash)"
+		_pip_completion "$@"
+	fi
+}
+complete -o default -F __bash_it_complete_pip3 pip3
diff --git a/completion/available/sdkman.completion.bash b/completion/available/sdkman.completion.bash
index 7f0157f335..2dc090887a 100644
--- a/completion/available/sdkman.completion.bash
+++ b/completion/available/sdkman.completion.bash
@@ -1,7 +1,9 @@
 # shellcheck shell=bash
-_sdkman_complete() {
+
+function _sdkman_complete() {
 	local CANDIDATES
 	local CANDIDATE_VERSIONS
+	local SDKMAN_CANDIDATES_CSV="${SDKMAN_CANDIDATES_CSV:-}"
 
 	COMPREPLY=()
 
@@ -10,7 +12,7 @@ _sdkman_complete() {
 	elif [ "$COMP_CWORD" -eq 2 ]; then
 		case "${COMP_WORDS[COMP_CWORD - 1]}" in
 			"install" | "i" | "uninstall" | "rm" | "list" | "ls" | "use" | "u" | "default" | "d" | "home" | "h" | "current" | "c" | "upgrade" | "ug")
-				CANDIDATES=$(echo "${SDKMAN_CANDIDATES_CSV}" | tr ',' ' ')
+				CANDIDATES="${SDKMAN_CANDIDATES_CSV//,/${IFS:0:1}}"
 				mapfile -t COMPREPLY < <(compgen -W "$CANDIDATES" -- "${COMP_WORDS[COMP_CWORD]}")
 				;;
 			"env")
@@ -46,17 +48,17 @@ _sdkman_complete() {
 	return 0
 }
 
-_sdkman_candidate_local_versions() {
+function _sdkman_candidate_local_versions() {
 
 	CANDIDATE_VERSIONS=$(__sdkman_cleanup_local_versions "$1")
 
 }
 
-_sdkman_candidate_all_versions() {
+function _sdkman_candidate_all_versions() {
 
 	candidate="$1"
 	CANDIDATE_LOCAL_VERSIONS=$(__sdkman_cleanup_local_versions "$candidate")
-	if [ "$SDKMAN_OFFLINE_MODE" = "true" ]; then
+	if [[ "${SDKMAN_OFFLINE_MODE:-false}" == "true" ]]; then
 		CANDIDATE_VERSIONS=$CANDIDATE_LOCAL_VERSIONS
 	else
 		# sdkman has a specific output format for Java candidate since
@@ -70,12 +72,12 @@ _sdkman_candidate_all_versions() {
 		# "+" - local version
 		# "*" - installed
 		# ">" - currently in use
-		CANDIDATE_VERSIONS="$(echo "$CANDIDATE_ONLINE_VERSIONS $CANDIDATE_LOCAL_VERSIONS" | tr ' ' '\n' | grep -v -e '^[[:space:]|\*|\>|\+]*$' | sort | uniq -u) "
+		CANDIDATE_VERSIONS="$(echo "$CANDIDATE_ONLINE_VERSIONS $CANDIDATE_LOCAL_VERSIONS" | tr ' ' '\n' | grep -v -e '^[[:space:]|\*|\>|\+]*$' | sort -u) "
 	fi
 
 }
 
-__sdkman_cleanup_local_versions() {
+function __sdkman_cleanup_local_versions() {
 
 	__sdkman_build_version_csv "$1" | tr ',' ' '
 
diff --git a/completion/available/sqlmap.completion.bash b/completion/available/sqlmap.completion.bash
index 16addf8545..213dd81736 100644
--- a/completion/available/sqlmap.completion.bash
+++ b/completion/available/sqlmap.completion.bash
@@ -1,21 +1,22 @@
-#!/bin/bash
+# shellcheck shell=bash
 
 # ---------------------------------------------------------------------------+
 #                                                                            |
-# Thanks to Alexander Korznikov                                                                 |
+# Thanks to Alexander Korznikov                                              |
 # http://www.korznikov.com/2014/12/bash-tab-completion-for-awesome-tool.html |
 #                                                                            |
 # ---------------------------------------------------------------------------+
 
-if command -v sqlmap > /dev/null; then
+if _command_exists sqlmap
+then
 
-    _sqlmap()
+    function _sqlmap()
     {
         local cur prev
 
         COMPREPLY=()
-        cur=$(_get_cword)
-        prev=$(_get_pword)
+        cur="$(_get_cword)"
+        prev="$(_get_pword)"
 
         case $prev in
 
@@ -143,7 +144,7 @@ if command -v sqlmap > /dev/null; then
         --mobile --page-rank --purge-output --smart \
         --sqlmap-shell --wizard '
         COMPREPLY=( $( \
-            (while read -d ' ' i; do
+		(while read -d ' ' i; do
                 [[ -z "$i" || "${onlyonce/ ${i%% *} / }" == "$onlyonce" ]] &&
                 continue
                 # flatten array with spaces on either side,
@@ -152,7 +153,7 @@ if command -v sqlmap > /dev/null; then
                 COMPREPLY=" ${COMPREPLY[@]} "
                 # remove word from list of completions
                 COMPREPLY=( ${COMPREPLY/ ${i%% *} / } )
-                done
+			done
                 printf '%s ' "${COMPREPLY[@]}") <<<"${COMP_WORDS[@]}"
             ) )
 
diff --git a/completion/available/system.completion.bash b/completion/available/system.completion.bash
index 8c4f71dcea..113a93f5be 100644
--- a/completion/available/system.completion.bash
+++ b/completion/available/system.completion.bash
@@ -1,9 +1,21 @@
 #!/usr/bin/env bash
-
+#
 # Loads the system's Bash completion modules.
 # If Homebrew is installed (OS X), it's Bash completion modules are loaded.
 
-if [[ -r /etc/bash_completion ]] ; then
+if shopt -qo nounset
+then # Bash-completion is too large and complex to expect to handle unbound variables throughout the whole codebase.
+	__bash_it_restore_nounset=true
+	shopt -uo nounset
+else
+	__bash_it_restore_nounset=false
+fi
+
+if [[ -r "${BASH_COMPLETION:-}" ]] ; then
+  # shellcheck disable=SC1091
+	source "${BASH_COMPLETION}"
+
+elif [[ -r /etc/bash_completion ]] ; then
   # shellcheck disable=SC1091
   source /etc/bash_completion
 
@@ -12,14 +24,36 @@ elif [[ -r /etc/profile.d/bash_completion.sh ]] ; then
   # shellcheck disable=SC1091
   source /etc/profile.d/bash_completion.sh
 
-fi
+elif _bash_it_homebrew_check
+then
+  : ${BASH_COMPLETION_COMPAT_DIR:=$BASH_IT_HOMEBREW_PREFIX/etc/bash_completion.d}
 
-if [[ "$(uname -s)" == 'Darwin' ]] && _command_exists brew ; then
-  BREW_PREFIX=${BREW_PREFIX:-$(brew --prefix)}
+  case "${BASH_VERSION}" in
+  1*|2*|3.0*|3.1*)
+    _log_warning "Cannot load completion due to version of shell. Are you using Bash 3.2+?"
+    ;;
+  3.2*|4.0*|4.1*)
+    # Import version 1.x of bash-completion, if installed.
+    BASH_COMPLETION="$BASH_IT_HOMEBREW_PREFIX/opt/bash-completion@1/etc/bash_completion"
+    if [[ -r "$BASH_COMPLETION" ]] ; then
+      # shellcheck disable=SC1090
+      source "$BASH_COMPLETION"
+    else
+      unset BASH_COMPLETION
+    fi
+    ;;
+  4.2*|5*|*)
+    # homebrew/versions/bash-completion2 (required for projects.completion.bash) is installed to this path
+    if [[ -r "$BASH_IT_HOMEBREW_PREFIX"/etc/profile.d/bash_completion.sh ]] ; then
+      # shellcheck disable=SC1090
+      source "$BASH_IT_HOMEBREW_PREFIX"/etc/profile.d/bash_completion.sh
+    fi
+    ;;
+  esac
+fi
 
-  # homebrew/versions/bash-completion2 (required for projects.completion.bash) is installed to this path
-  if [[ -r "$BREW_PREFIX"/etc/profile.d/bash_completion.sh ]] ; then
-    # shellcheck disable=SC1090
-    source "$BREW_PREFIX"/etc/profile.d/bash_completion.sh
-  fi
+if $__bash_it_restore_nounset
+then
+	shopt -so nounset
 fi
+unset __bash_it_restore_nounset
diff --git a/completion/available/travis.completion.bash b/completion/available/travis.completion.bash
index 28d599aaca..49d8f2cc92 100644
--- a/completion/available/travis.completion.bash
+++ b/completion/available/travis.completion.bash
@@ -1,5 +1,10 @@
-if [[ -x "$(which travis)" ]]; then
-  __TRAVIS_COMPLETION_SCRIPT="${TRAVIS_CONFIG_PATH:-${HOME}/.travis}/travis.sh"
-  [[ -f "${__TRAVIS_COMPLETION_SCRIPT}" ]] && source "${__TRAVIS_COMPLETION_SCRIPT}"
+# shellcheck shell=bash
+
+if _command_exists travis
+then
+  if [[ -s "${__TRAVIS_COMPLETION_SCRIPT:=${TRAVIS_CONFIG_PATH:-${HOME}/.travis}/travis.sh}" ]]
+	then
+		source "${__TRAVIS_COMPLETION_SCRIPT}"
+	fi
   unset __TRAVIS_COMPLETION_SCRIPT
 fi
diff --git a/completion/available/vuejs.completion.bash b/completion/available/vuejs.completion.bash
index bbd79b9c9b..751658f0c9 100644
--- a/completion/available/vuejs.completion.bash
+++ b/completion/available/vuejs.completion.bash
@@ -1,7 +1,9 @@
 # shellcheck shell=bash
 
 __vuejs_completion() {
+	# shellcheck disable=SC2155
 	local prev=$(_get_pword)
+	# shellcheck disable=SC2155
 	local curr=$(_get_cword)
 
 	case $prev in
diff --git a/completion/available/wpscan.completion.bash b/completion/available/wpscan.completion.bash
index f9ea5790df..105468a356 100644
--- a/completion/available/wpscan.completion.bash
+++ b/completion/available/wpscan.completion.bash
@@ -1,15 +1,16 @@
-#!/usr/bin/bash
+# shellcheck shell=bash
 
-if command -v wpscan > /dev/null; then
-    __wpscan_completion()  {
-        local OPTS=("--help --hh --version --url --ignore-main-redirect --verbose --output --format --detection-mode --scope --headers --user-agent --vhost --random-user-agent --user-agents-list --http-auth --max-threads --throttle --request-timeout --connect-timeout --disable-tlc-checks --proxy --proxy-auth --cookie-string --cookie-jar --cache-ttl --clear-cache --server --cache-dir --update --no-update --wp-content-dir --wp-plugins-dir --wp-version-detection --main-theme-detection --enumerate --exclude-content-based --plugins-list --plugins-detection --plugins-version-all --plugins-version-detection --themes-list --themes-detection --themes-version-all --themes-version-detection --timthumbs-list --timthumbs-detection --config-backups-list --config-backups-detection --db-exports-list --db-exports-detection --medias-detection --users-list --users-detection --passwords --usernames --multicall-max-passwords --password-attack --stealthy")
-        COMPREPLY=()
-        for _opt_ in ${OPTS[@]}; do
-            if [[ "$_opt_" == "$2"* ]]; then
-                COMPREPLY+=("$_opt_")
-            fi
-        done
-    }
+_command_exists wpscan || return
 
-    complete -F __wpscan_completion wpscan
-fi
+function __wpscan_completion() {
+	local _opt_
+	local OPTS=('--help' '--hh' '--version' '--url' '--ignore-main-redirect' '--verbose' '--output' '--format' '--detection-mode' '--scope' '--headers' '--user-agent' '--vhost' '--random-user-agent' '--user-agents-list' '--http-auth' '--max-threads' '--throttle' '--request-timeout' '--connect-timeout' '--disable-tlc-checks' '--proxy' '--proxy-auth' '--cookie-string' '--cookie-jar' '--cache-ttl' '--clear-cache' '--server' '--cache-dir' '--update' '--no-update' '--wp-content-dir' '--wp-plugins-dir' '--wp-version-detection' '--main-theme-detection' '--enumerate' '--exclude-content-based' '--plugins-list' '--plugins-detection' '--plugins-version-all' '--plugins-version-detection' '--themes-list' '--themes-detection' '--themes-version-all' '--themes-version-detection' '--timthumbs-list' '--timthumbs-detection' '--config-backups-list' '--config-backups-detection' '--db-exports-list' '--db-exports-detection' '--medias-detection' '--users-list' '--users-detection' '--passwords' '--usernames' '--multicall-max-passwords' '--password-attack' '--stealthy')
+	COMPREPLY=()
+	for _opt_ in "${OPTS[@]}"; do
+		if [[ "$_opt_" == "$2"* ]]; then
+			COMPREPLY+=("$_opt_")
+		fi
+	done
+}
+
+complete -F __wpscan_completion wpscan
diff --git a/docs/README.md b/docs/README.md
index fe18c80e17..33c1b03f07 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -4,7 +4,7 @@
 ![Docs Status](https://readthedocs.org/projects/bash-it/badge/)
 ![License](https://img.shields.io/github/license/Bash-it/bash-it)
 ![shell](https://img.shields.io/badge/Shell-Bash-blue)
-[![Join the chat at https://webchat.freenode.net/?channel=#bash-it](https://img.shields.io/badge/chat-on%20freenode-brightgreen.svg)](https://webchat.freenode.net/?channel=#bash-it)
+[![Join the chat at https://web.libera.chat/?channel=#bash-it](https://img.shields.io/badge/chat-on%20Libera.Chat-brightgreen.svg)](https://web.libera.chat/?channel=#bash-it)
 
 **Bash-it** is a collection of community Bash commands and scripts for Bash 3.2+.
 (And a shameless ripoff of [oh-my-zsh](https://github.com/robbyrussell/oh-my-zsh) :smiley:)
diff --git a/docs/themes-list/powerline-base.rst b/docs/themes-list/powerline-base.rst
index 85ba2388d1..faa1af3401 100644
--- a/docs/themes-list/powerline-base.rst
+++ b/docs/themes-list/powerline-base.rst
@@ -70,11 +70,13 @@ The contents of the prompt can be "reordered", all the "segments" (every piece o
 * ``battery`` - Battery information (you'll need to enable the ``battery`` plugin)
 * ``clock`` - Current time in ``HH:MM:SS`` format
 * ``cwd`` - Current working directory including full folder hierarchy (c.f. ``wd``\ )
+* ``duration`` - Duration of the last command. See :ref:`Command duration <command_duration>` for details.
 * ``gcloud`` - Current gcloud active account
 * ``hostname`` - Host name of machine
 * ``in_toolbox`` - Show identifier if running inside a `toolbox <https://github.com/containers/toolbox>`_
 * ``in_vim`` - Show identifier if running in ``:terminal`` from vim
 * ``k8s_context`` - Show current kubernetes context
+* ``k8s_namespace`` - Show current kubernetes namespace
 * ``last_status`` - Exit status of last run command
 * ``python_venv`` - Python virtual environment information (\ ``virtualenv``\ , ``venv``
   and ``conda`` supported)
diff --git a/hooks/dot-bash.sh b/hooks/dot-bash.sh
index 7a9dc8bcaf..253cb595e4 100755
--- a/hooks/dot-bash.sh
+++ b/hooks/dot-bash.sh
@@ -18,4 +18,4 @@ for file in "$@"; do
 	fi
 done
 
-exit $exit_code
+exit "${exit_code:-0}"
diff --git a/hooks/dot-sh.sh b/hooks/dot-sh.sh
index 3fa63216db..e1086bb62f 100755
--- a/hooks/dot-sh.sh
+++ b/hooks/dot-sh.sh
@@ -18,4 +18,4 @@ for file in "$@"; do
 	fi
 done
 
-exit $exit_code
+exit "${exit_code:-0}"
diff --git a/install.sh b/install.sh
index 4940360f87..5d2f883e90 100755
--- a/install.sh
+++ b/install.sh
@@ -83,8 +83,8 @@ function _bash-it_check_for_backup() {
 	fi
 	echo -e "\033[0;33mBackup file already exists. Make sure to backup your .bashrc before running this installation.\033[0m" >&2
 
-	if ! [[ $overwrite_backup ]]; then
-		while ! [[ $silent ]]; do
+	if [[ -z "${overwrite_backup}" ]]; then
+		while [[ -z "${silent}" ]]; do
 			read -e -n 1 -r -p "Would you like to overwrite the existing backup? This will delete your existing backup file ($HOME/$BACKUP_FILE) [y/N] " RESP
 			case $RESP in
 				[yY])
@@ -100,9 +100,9 @@ function _bash-it_check_for_backup() {
 			esac
 		done
 	fi
-	if ! [[ $overwrite_backup ]]; then
+	if [[ -z "${overwrite_backup}" ]]; then
 		echo -e "\033[91mInstallation aborted. Please come back soon!\033[m"
-		if [[ $silent ]]; then
+		if [[ -n "${silent}" ]]; then
 			echo -e "\033[91mUse \"-f\" flag to force overwrite of backup.\033[m"
 		fi
 		exit 1
@@ -114,8 +114,8 @@ function _bash-it_check_for_backup() {
 function _bash-it_modify_config_files() {
 	_bash-it_check_for_backup
 
-	if ! [[ $silent ]]; then
-		while ! [[ $append_to_config ]]; do
+	if [[ -z "${silent}" ]]; then
+		while [[ -z "${append_to_config}" ]]; do
 			read -e -n 1 -r -p "Would you like to keep your $CONFIG_FILE and append bash-it templates at the end? [y/N] " choice
 			case $choice in
 				[yY])
@@ -131,7 +131,7 @@ function _bash-it_modify_config_files() {
 			esac
 		done
 	fi
-	if [[ $append_to_config ]]; then
+	if [[ -n "${append_to_config}" ]]; then
 		# backup/append
 		_bash-it_backup_append
 	else
@@ -174,17 +174,17 @@ done
 
 shift $((OPTIND - 1))
 
-if [[ $silent ]] && [[ $interactive ]]; then
+if [[ -n "${silent}" && -n "${interactive}" ]]; then
 	echo -e "\033[91mOptions --silent and --interactive are mutually exclusive. Please choose one or the other.\033[m"
 	exit 1
 fi
 
-if [[ $no_modify_config ]] && [[ $append_to_config ]]; then
+if [[ -n "${no_modify_config}" && -n "${append_to_config}" ]]; then
 	echo -e "\033[91mOptions --no-modify-config and --append-to-config are mutually exclusive. Please choose one or the other.\033[m"
 	exit 1
 fi
 
-BASH_IT="$(cd "$(dirname "$0")" && pwd)"
+BASH_IT="$(cd "${BASH_SOURCE%/*}" && pwd)"
 
 case $OSTYPE in
 	darwin*)
@@ -197,7 +197,7 @@ esac
 
 BACKUP_FILE=$CONFIG_FILE.bak
 echo "Installing bash-it"
-if ! [[ $no_modify_config ]]; then
+if [[ -z "${no_modify_config}" ]]; then
 	_bash-it_modify_config_files
 fi
 
@@ -212,10 +212,10 @@ cite _about _param _example _group _author _version
 # shellcheck source=./lib/helpers.bash
 source "$BASH_IT/lib/helpers.bash"
 
-if [[ $interactive ]] && ! [[ $silent ]]; then
+if [[ -n $interactive && -z "${silent}" ]]; then
 	for type in "aliases" "plugins" "completion"; do
-		echo -e "\033[0;32mEnabling $type\033[0m"
-		_bash-it_load_some $type
+		echo -e "\033[0;32mEnabling ${type}\033[0m"
+		_bash-it_load_some "$type"
 	done
 else
 	echo ""
@@ -230,7 +230,7 @@ fi
 echo ""
 echo -e "\033[0;32mInstallation finished successfully! Enjoy bash-it!\033[0m"
 # shellcheck disable=SC2086
-echo -e "\033[0;32mTo start using it, open a new tab or 'source "$HOME/$CONFIG_FILE"'.\033[0m"
+echo -e "\033[0;32mTo start using it, open a new tab or 'source "~/$CONFIG_FILE"'.\033[0m"
 echo ""
 echo "To show the available aliases/completions/plugins, type one of the following:"
 echo "  bash-it show aliases"
diff --git a/lib/helpers.bash b/lib/helpers.bash
old mode 100644
new mode 100755
index bf63c362d4..94df885d42
--- a/lib/helpers.bash
+++ b/lib/helpers.bash
@@ -11,8 +11,8 @@ BASH_IT_LOAD_PRIORITY_SEPARATOR="---"
 # To use this in Bash-it for inline replacements with `sed`, use the following syntax:
 # sed "${BASH_IT_SED_I_PARAMETERS[@]}" -e "..." file
 BASH_IT_SED_I_PARAMETERS=(-i)
-case "$(uname)" in
-  Darwin*) BASH_IT_SED_I_PARAMETERS=(-i "")
+case "$OSTYPE" in
+  'darwin'*) BASH_IT_SED_I_PARAMETERS=(-i "")
 esac
 
 function _command_exists ()
@@ -23,7 +23,13 @@ function _command_exists ()
   _example '$ _command_exists ls && echo exists'
   _group 'lib'
   local msg="${2:-Command '$1' does not exist!}"
-  type "$1" &> /dev/null || (_log_warning "$msg" && return 1) ;
+  if type -t "$1" &> /dev/null
+  then
+	  return 0
+  else
+	  _log_warning "$msg"
+	  return 1
+  fi
 }
 
 function _binary_exists ()
@@ -34,7 +40,13 @@ function _binary_exists ()
   _example '$ _binary_exists ls && echo exists'
   _group 'lib'
   local msg="${2:-Binary '$1' does not exist!}"
-  type -P "$1" &> /dev/null || (_log_warning "$msg" && return 1) ;
+  if type -P "$1" &> /dev/null
+  then
+	return 0
+  else
+	_log_warning "$msg"
+	return 1
+  fi
 }
 
 function _completion_exists ()
@@ -48,6 +60,22 @@ function _completion_exists ()
   complete -p "$1" &> /dev/null && _log_warning "$msg" ;
 }
 
+function _bash_it_homebrew_check()
+{
+	if _binary_exists 'brew'
+	then # Homebrew is installed
+		if [[ "${BASH_IT_HOMEBREW_PREFIX:-unset}" == 'unset' ]]
+		then # variable isn't set
+			BASH_IT_HOMEBREW_PREFIX="$(brew --prefix)"
+		else
+			true # Variable is set already, don't invoke `brew`.
+		fi
+	else # Homebrew is not installed.
+		BASH_IT_HOMEBREW_PREFIX= # clear variable, if set to anything.
+		false # return failure if brew not installed.
+	fi
+}
+
 function _make_reload_alias() {
   echo "source \${BASH_IT}/scripts/reloader.bash ${1} ${2}"
 }
@@ -140,7 +168,7 @@ bash-it ()
             $func $arg
         done
 
-        if [ -n "$BASH_IT_AUTOMATIC_RELOAD_AFTER_CONFIG_CHANGE" ]; then
+        if [ -n "${BASH_IT_AUTOMATIC_RELOAD_AFTER_CONFIG_CHANGE:-}" ]; then
           _bash-it-reload
         fi
     else
@@ -194,7 +222,10 @@ _bash-it-update-stable() {
   _bash-it-update- stable "$@"
 }
 
-_bash-it_pull_and_update_inner() {
+_bash-it_update_migrate_and_restart() {
+	_about 'Checks out the wanted version, pops directory and restart. Does not return (because of the restart!)'
+  _param '1: Which branch to checkout to'
+  _param '2: Which type of version we are using'
   git checkout "$1" &> /dev/null
   if [[ $? -eq 0 ]]; then
     echo "Bash-it successfully updated."
@@ -203,7 +234,9 @@ _bash-it_pull_and_update_inner() {
     _bash-it-migrate
     echo ""
     echo "All done, enjoy!"
-    bash-it reload
+    # Don't forget to restore the original pwd!
+    popd &> /dev/null
+    _bash-it-restart
   else
     echo "Error updating Bash-it, please, check if your Bash-it installation folder (${BASH_IT}) is clean."
   fi
@@ -220,9 +253,11 @@ _bash-it-update-() {
       silent=true
     fi
   done
-  local old_pwd="${PWD}"
 
-  cd "${BASH_IT}" || return
+  pushd "${BASH_IT}" &> /dev/null || return
+
+  DIFF=$(git diff --name-status)
+  [ -n "$DIFF" ] && echo -e "Local changes detected in bash-it directory. Clean '$BASH_IT' directory to proceed.\n$DIFF" && return 1
 
   if [ -z "$BASH_IT_REMOTE" ]; then
     BASH_IT_REMOTE="origin"
@@ -240,6 +275,7 @@ _bash-it-update-() {
 
     if [[ -z "$TARGET" ]]; then
       echo "Can not find tags, so can not update to latest stable version..."
+      popd &> /dev/null
       return
     fi
   else
@@ -280,12 +316,12 @@ _bash-it-update-() {
 
     if [[ $silent ]]; then
       echo "Updating to ${TARGET}($(git log -1 --format=%h "${TARGET}"))..."
-      _bash-it_pull_and_update_inner $TARGET $version
+      _bash-it_update_migrate_and_restart $TARGET $version
     else
       read -e -n 1 -p "Would you like to update to ${TARGET}($(git log -1 --format=%h "${TARGET}"))? [Y/n] " RESP
       case $RESP in
         [yY]|"")
-          _bash-it_pull_and_update_inner $TARGET $version
+          _bash-it_update_migrate_and_restart $TARGET $version
           ;;
         [nN])
           echo "Not updating…"
@@ -302,7 +338,7 @@ _bash-it-update-() {
       echo "Bash-it is up to date, nothing to do!"
     fi
   fi
-  cd "${old_pwd}" &> /dev/null || return
+  popd &> /dev/null
 }
 
 _bash-it-migrate() {
@@ -316,7 +352,7 @@ _bash-it-migrate() {
   do
     for f in `sort <(compgen -G "${BASH_IT}/$file_type/enabled/*.bash")`
     do
-      typeset ff=$(basename $f)
+      typeset ff="${f##*/}"
 
       # Get the type of component from the extension
       typeset single_type=$(echo $ff | sed -e 's/.*\.\(.*\)\.bash/\1/g' | sed 's/aliases/alias/g')
@@ -330,8 +366,8 @@ _bash-it-migrate() {
       disable_func="_disable-$single_type"
       enable_func="_enable-$single_type"
 
-      $disable_func $component_name
-      $enable_func $component_name
+      $disable_func "$component_name"
+      $enable_func "$component_name"
     done
   done
 
@@ -351,7 +387,7 @@ _bash-it-version() {
 
   cd "${BASH_IT}" || return
 
-  if [ -z $BASH_IT_REMOTE ]; then
+  if [ -z "${BASH_IT_REMOTE:-}" ]; then
     BASH_IT_REMOTE="origin"
   fi
 
@@ -425,7 +461,7 @@ _bash-it-restart() {
   _about 'restarts the shell in order to fully reload it'
   _group 'lib'
 
-  saved_pwd=$(pwd)
+  saved_pwd="${PWD}"
 
   case $OSTYPE in
     darwin*)
@@ -477,7 +513,7 @@ _bash-it-describe ()
     do
         # Check for both the old format without the load priority, and the extended format with the priority
         declare enabled_files enabled_file
-        enabled_file=$(basename $f)
+		enabled_file="${f##*/}"
         enabled_files=$(sort <(compgen -G "${BASH_IT}/enabled/*$BASH_IT_LOAD_PRIORITY_SEPARATOR${enabled_file}") <(compgen -G "${BASH_IT}/$subdirectory/enabled/${enabled_file}") <(compgen -G "${BASH_IT}/$subdirectory/enabled/*$BASH_IT_LOAD_PRIORITY_SEPARATOR${enabled_file}") | wc -l)
 
         if [ $enabled_files -gt 0 ]; then
@@ -579,9 +615,9 @@ _disable-thing ()
               printf '%s\n' "sorry, $file_entity does not appear to be an enabled $file_type."
               return
           fi
-          rm "${BASH_IT}/$subdirectory/enabled/$(basename $plugin)"
+          rm "${BASH_IT}/$subdirectory/enabled/${plugin##*/}"
         else
-          rm "${BASH_IT}/enabled/$(basename $plugin_global)"
+          rm "${BASH_IT}/enabled/${plugin_global##*/}"
         fi
     fi
 
@@ -657,7 +693,7 @@ _enable-thing ()
             return
         fi
 
-        to_enable=$(basename $to_enable)
+		to_enable="${to_enable##*/}"
         # Check for existence of the file using a wildcard, since we don't know which priority might have been used when enabling it.
         typeset enabled_plugin=$(command ls "${BASH_IT}/$subdirectory/enabled/"{[0-9][0-9][0-9]$BASH_IT_LOAD_PRIORITY_SEPARATOR$to_enable,$to_enable} 2>/dev/null | head -1)
         if [ ! -z "$enabled_plugin" ] ; then
@@ -813,3 +849,30 @@ then
     fi
   }
 fi
+
+# `_bash-it-find-in-ancestor` uses the shell's ability to run a function in
+# a subshell to simplify our search to a simple `cd ..` and `[[ -r $1 ]]`
+# without any external dependencies. Let the shell do what it's good at.
+function _bash-it-find-in-ancestor() (
+	about 'searches parents of the current directory for any of the specified file names'
+	group 'helpers'
+	param '*: names of files or folders to search for'
+	returns '0: prints path of closest matching ancestor directory to stdout'
+	returns '1: no match found'
+	returns '2: improper usage of shell builtin' # uncommon
+	example '_bash-it-find-in-ancestor .git .hg'
+	example '_bash-it-find-in-ancestor GNUmakefile Makefile makefile'
+
+	local kin
+	# To keep things simple, we do not search the root dir.
+	while [[ "${PWD}" != '/' ]]; do
+		for kin in "$@"; do
+			if [[ -r "${PWD}/${kin}" ]]; then
+				printf '%s' "${PWD}"
+				return "$?"
+			fi
+		done
+		command cd .. || return "$?"
+	done
+	return 1
+)
diff --git a/lib/log.bash b/lib/log.bash
index 105c9064a1..6bc53a1239 100644
--- a/lib/log.bash
+++ b/lib/log.bash
@@ -22,8 +22,8 @@ function _log_general()
   param '3: message to log'
   group 'log'
 
-  message=$2${BASH_IT_LOG_PREFIX}$3
-  _has_colors && echo -e "$1${message}${echo_normal}" || echo -e "${message}"
+  message=$2${BASH_IT_LOG_PREFIX:-default: }$3
+  _has_colors && echo -e "$1${message}${echo_normal:-}" || echo -e "${message}"
 }
 
 function _log_debug()
@@ -33,8 +33,8 @@ function _log_debug()
   example '$ _log_debug "Loading plugin git..."'
   group 'log'
 
-  [[ "$BASH_IT_LOG_LEVEL" -ge $BASH_IT_LOG_LEVEL_ALL ]] || return 0
-  _log_general "${echo_green}" "DEBUG: " "$1"
+  [[ "${BASH_IT_LOG_LEVEL:-0}" -ge $BASH_IT_LOG_LEVEL_ALL ]] || return 0
+  _log_general "${echo_green:-}" "DEBUG: " "$1"
 }
 
 function _log_warning()
@@ -44,8 +44,8 @@ function _log_warning()
   example '$ _log_warning "git binary not found, disabling git plugin..."'
   group 'log'
 
-  [[ "$BASH_IT_LOG_LEVEL" -ge $BASH_IT_LOG_LEVEL_WARNING ]] || return 0
-  _log_general "${echo_yellow}" " WARN: " "$1"
+  [[ "${BASH_IT_LOG_LEVEL:-0}" -ge $BASH_IT_LOG_LEVEL_WARNING ]] || return 0
+  _log_general "${echo_yellow:-}" " WARN: " "$1"
 }
 
 function _log_error()
@@ -55,6 +55,6 @@ function _log_error()
   example '$ _log_error "Failed to load git plugin..."'
   group 'log'
 
-  [[ "$BASH_IT_LOG_LEVEL" -ge $BASH_IT_LOG_LEVEL_ERROR ]] || return 0
-  _log_general "${echo_red}" "ERROR: " "$1"
+  [[ "${BASH_IT_LOG_LEVEL:-0}" -ge $BASH_IT_LOG_LEVEL_ERROR ]] || return 0
+  _log_general "${echo_red:-}" "ERROR: " "$1"
 }
diff --git a/lib/preview.bash b/lib/preview.bash
index d0fb0623ba..418839cd2d 100644
--- a/lib/preview.bash
+++ b/lib/preview.bash
@@ -1,4 +1,4 @@
-if [[ $BASH_PREVIEW ]];
+if [[ "${BASH_PREVIEW:-}" ]];
 then
   unset BASH_PREVIEW #Prevent infinite looping
   echo "
diff --git a/lib/search.bash b/lib/search.bash
old mode 100755
new mode 100644
diff --git a/lib/utilities.bash b/lib/utilities.bash
index db63956d74..84fa4d96b2 100644
--- a/lib/utilities.bash
+++ b/lib/utilities.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 #
 # A collection of reusable functions.
 
@@ -6,22 +6,25 @@
 # Generic utilies
 ###########################################################################
 
-_bash-it-get-component-name-from-path() {
-  # filename without path
-  filename=${1##*/}
-  # filename without path or priority
-  filename=${filename##*---}
-  # filename without path, priority or extension
-  echo ${filename%.*.bash}
+function _bash-it-get-component-name-from-path() {
+	local filename
+	# filename without path
+	filename="${1##*/}"
+	# filename without path or priority
+	filename="${filename##*${BASH_IT_LOAD_PRIORITY_SEPARATOR?}}"
+	# filename without path, priority or extension
+	echo "${filename%.*.bash}"
 }
 
-_bash-it-get-component-type-from-path() {
-  # filename without path
-  filename=${1##*/}
-  # filename without path or priority
-  filename=${filename##*---}
-  # extension
-  echo ${filename} | cut -d '.' -f 2
+function _bash-it-get-component-type-from-path() {
+	local filename
+	# filename without path
+	filename="${1##*/}"
+	# filename without extension
+	filename="${filename%.bash}"
+	# extension without priority or name
+	filename="${filename##*.}"
+	echo "${filename}"
 }
 
 # This function searches an array for an exact match against the term passed
@@ -43,96 +46,97 @@ _bash-it-get-component-type-from-path() {
 #   contains pear!
 #
 #
-_bash-it-array-contains-element() {
-  local e
-  for e in "${@:2}"; do
-    [[ "$e" == "$1" ]] && return 0
-  done
-  return 1
+function _bash-it-array-contains-element() {
+	local e
+	for e in "${@:2}"; do
+		[[ "$e" == "$1" ]] && return 0
+	done
+	return 1
 }
 
 # Dedupe a simple array of words without spaces.
-_bash-it-array-dedup() {
-  echo "$*" | tr ' ' '\n' | sort -u | tr '\n' ' '
+function _bash-it-array-dedup() {
+	local IFS=$'\n'
+	echo "$@" | tr ' ' '\n' | sort -u
 }
 
 # Outputs a full path of the grep found on the filesystem
-_bash-it-grep() {
-  if [[ -z "${BASH_IT_GREP}" ]] ; then
-    export BASH_IT_GREP="$(which egrep || which grep || '/usr/bin/grep')"
-  fi
-  printf "%s " "${BASH_IT_GREP}"
+function _bash-it-grep() {
+	: "${BASH_IT_GREP:=$(type -p egrep || type -p grep)}"
+	printf "%s" "${BASH_IT_GREP:-'/usr/bin/grep'}"
 }
 
-
 ###########################################################################
 # Component-specific functions (component is either an alias, a plugin, or a
 # completion).
 ###########################################################################
 
-_bash-it-component-help() {
-  local component=$(_bash-it-pluralize-component "${1}")
-  local file=$(_bash-it-component-cache-file ${component})
-  if [[ ! -s "${file}" || -z $(find "${file}" -mmin -300) ]] ; then
-    rm -f "${file}" 2>/dev/null
-    local func="_bash-it-${component}"
-    ${func} | $(_bash-it-grep) -E '   \[' | cat > ${file}
-  fi
-  cat "${file}"
+function _bash-it-component-help() {
+	local component file func
+	component="$(_bash-it-pluralize-component "${1}")"
+	file="$(_bash-it-component-cache-file "${component}")"
+	if [[ ! -s "${file}" || -z "$(find "${file}" -mmin -300)" ]]; then
+		rm -f "${file}" 2> /dev/null
+		func="_bash-it-${component}"
+		"${func}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E '   \[' > "${file}"
+	fi
+	cat "${file}"
 }
 
-_bash-it-component-cache-file() {
-  local component=$(_bash-it-pluralize-component "${1}")
-  local file="${BASH_IT}/tmp/cache/${component}"
-  [[ -f ${file} ]] || mkdir -p $(dirname ${file})
-  printf "${file}"
+function _bash-it-component-cache-file() {
+	local component file
+	component="$(_bash-it-pluralize-component "${1}")"
+	file="${BASH_IT?}/tmp/cache/${component}"
+	[[ -f "${file}" ]] || mkdir -p "${file%/*}"
+	printf '%s' "${file}"
 }
 
-_bash-it-pluralize-component() {
-  local component="${1}"
-  local len=$(( ${#component} - 1 ))
-  # pluralize component name for consistency
-  [[ ${component:${len}:1} != 's' ]] && component="${component}s"
-  [[ ${component} == "alias" ]] && component="aliases"
-  printf ${component}
+function _bash-it-pluralize-component() {
+	local component="${1}"
+	local -i len=$((${#component} - 1))
+	# pluralize component name for consistency
+	[[ "${component:${len}:1}" != 's' ]] && component="${component}s"
+	[[ "${component}" == "alias" ]] && component="aliases"
+	printf '%s' "${component}"
 }
 
-_bash-it-clean-component-cache() {
-  local component="$1"
-  local cache
-  local -a BASH_IT_COMPONENTS=(aliases plugins completions)
-  if [[ -z ${component} ]] ; then
-    for component in "${BASH_IT_COMPONENTS[@]}" ; do
-      _bash-it-clean-component-cache "${component}"
-    done
-  else
-    cache="$(_bash-it-component-cache-file ${component})"
-    if [[ -f "${cache}" ]] ; then
-      rm -f "${cache}"
-    fi
-  fi
+function _bash-it-clean-component-cache() {
+	local component="$1"
+	local cache
+	local -a BASH_IT_COMPONENTS=(aliases plugins completions)
+	if [[ -z "${component}" ]]; then
+		for component in "${BASH_IT_COMPONENTS[@]}"; do
+			_bash-it-clean-component-cache "${component}"
+		done
+	else
+		cache="$(_bash-it-component-cache-file "${component}")"
+		if [[ -f "${cache}" ]]; then
+			rm -f "${cache}"
+		fi
+	fi
 }
 
 # Returns an array of items within each compoenent.
-_bash-it-component-list() {
-  local component="$1"
-  _bash-it-component-help "${component}" | awk '{print $1}' | uniq | sort | tr '\n' ' '
+function _bash-it-component-list() {
+	local IFS=$'\n' component="$1"
+	_bash-it-component-help "${component}" | awk '{print $1}' | sort -u
 }
 
-_bash-it-component-list-matching() {
-  local component="$1"; shift
-  local term="$1"
-  _bash-it-component-help "${component}" | $(_bash-it-grep) -E -- "${term}" | awk '{print $1}' | sort | uniq
+function _bash-it-component-list-matching() {
+	local component="$1"
+	shift
+	local term="$1"
+	_bash-it-component-help "${component}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E -- "${term}" | awk '{print $1}' | sort -u
 }
 
-_bash-it-component-list-enabled() {
-  local component="$1"
-  _bash-it-component-help "${component}" | $(_bash-it-grep) -E  '\[x\]' | awk '{print $1}' | uniq | sort | tr '\n' ' '
+function _bash-it-component-list-enabled() {
+	local IFS=$'\n' component="$1"
+	_bash-it-component-help "${component}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E '\[x\]' | awk '{print $1}' | sort -u
 }
 
-_bash-it-component-list-disabled() {
-  local component="$1"
-  _bash-it-component-help "${component}" | $(_bash-it-grep) -E -v '\[x\]' | awk '{print $1}' | uniq | sort | tr '\n' ' '
+function _bash-it-component-list-disabled() {
+	local IFS=$'\n' component="$1"
+	_bash-it-component-help "${component}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E -v '\[x\]' | awk '{print $1}' | sort -u
 }
 
 # Checks if a given item is enabled for a particular component/file-type.
@@ -143,10 +147,10 @@ _bash-it-component-list-disabled() {
 #
 # Examples:
 #    _bash-it-component-item-is-enabled alias git && echo "git alias is enabled"
-_bash-it-component-item-is-enabled() {
-  local component="$1"
-  local item="$2"
-  _bash-it-component-help "${component}" | $(_bash-it-grep) -E '\[x\]' |  $(_bash-it-grep) -E -q -- "^${item}\s"
+function _bash-it-component-item-is-enabled() {
+	local component="$1"
+	local item="$2"
+	_bash-it-component-help "${component}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E '\[x\]' | ${BASH_IT_GREP:-$(_bash-it-grep)} -E -q -- "^${item}\s"
 }
 
 # Checks if a given item is disabled for a particular component/file-type.
@@ -157,8 +161,8 @@ _bash-it-component-item-is-enabled() {
 #
 # Examples:
 #    _bash-it-component-item-is-disabled alias git && echo "git aliases are disabled"
-_bash-it-component-item-is-disabled() {
-  local component="$1"
-  local item="$2"
-  _bash-it-component-help "${component}" | $(_bash-it-grep) -E -v '\[x\]' |  $(_bash-it-grep) -E -q -- "^${item}\s"
+function _bash-it-component-item-is-disabled() {
+	local component="$1"
+	local item="$2"
+	_bash-it-component-help "${component}" | ${BASH_IT_GREP:-$(_bash-it-grep)} -E -v '\[x\]' | ${BASH_IT_GREP:-$(_bash-it-grep)} -E -q -- "^${item}\s"
 }
diff --git a/plugins/available/alias-completion.plugin.bash b/plugins/available/alias-completion.plugin.bash
index 390b10e3cb..eb368d933c 100644
--- a/plugins/available/alias-completion.plugin.bash
+++ b/plugins/available/alias-completion.plugin.bash
@@ -19,6 +19,8 @@ about-plugin 'Automatic completion of aliases'
 # Automatically add completion for all aliases to commands having completion functions
 function alias_completion {
 	local namespace="alias_completion"
+	local tmp_file completion_loader alias_name alias_tokens line completions
+	local alias_arg_words new_completion compl_func compl_wrapper
 
 	# parse function based completion definitions, where capture group 2 => function and 3 => trigger
 	local compl_regex='complete( +[^ ]+)* -F ([^ ]+) ("[^"]+"|[^ ]+)'
@@ -26,28 +28,25 @@ function alias_completion {
 	local alias_regex="alias( -- | )([^=]+)='(\"[^\"]+\"|[^ ]+)(( +[^ ]+)*)'"
 
 	# create array of function completion triggers, keeping multi-word triggers together
-	eval "local completions=($(complete -p | sed -Ene "/$compl_regex/s//'\3'/p"))"
+	eval "completions=($(complete -p | sed -Ene "/$compl_regex/s//'\3'/p"))"
 	((${#completions[@]} == 0)) && return 0
 
 	# create temporary file for wrapper functions and completions
-	local tmp_file
 	tmp_file="$(mktemp -t "${namespace}-${RANDOM}XXXXXX")" || return 1
 
-	local completion_loader
 	completion_loader="$(complete -p -D 2> /dev/null | sed -Ene 's/.* -F ([^ ]*).*/\1/p')"
 
 	# read in "<alias> '<aliased command>' '<command args>'" lines from defined aliases
-	local line
-
-	# shellcheck disable=SC2162
 	# some aliases do have backslashes that needs to be interpreted
+	# shellcheck disable=SC2162
 	while read line; do
-		eval "local alias_tokens; alias_tokens=($line)" 2> /dev/null || continue # some alias arg patterns cause an eval parse error
-		local alias_name="${alias_tokens[0]}" alias_cmd="${alias_tokens[1]}" alias_args="${alias_tokens[2]# }"
+		eval "alias_tokens=($line)" 2> /dev/null || continue # some alias arg patterns cause an eval parse error
+		# shellcheck disable=SC2154 # see `eval` above
+		alias_name="${alias_tokens[0]}" alias_cmd="${alias_tokens[1]}" alias_args="${alias_tokens[2]# }"
 
 		# skip aliases to pipes, boolean control structures and other command lists
 		# (leveraging that eval errs out if $alias_args contains unquoted shell metacharacters)
-		eval "local alias_arg_words; alias_arg_words=($alias_args)" 2> /dev/null || continue
+		eval "alias_arg_words=($alias_args)" 2> /dev/null || continue
 		# avoid expanding wildcards
 		read -a alias_arg_words <<< "$alias_args"
 
@@ -63,15 +62,15 @@ function alias_completion {
 				continue
 			fi
 		fi
-		local new_completion="$(complete -p "$alias_cmd" 2> /dev/null)"
+		new_completion="$(complete -p "$alias_cmd" 2> /dev/null)"
 
 		# create a wrapper inserting the alias arguments if any
 		if [[ -n $alias_args ]]; then
-			local compl_func="${new_completion/#* -F /}"
+			compl_func="${new_completion/#* -F /}"
 			compl_func="${compl_func%% *}"
 			# avoid recursive call loops by ignoring our own functions
-			if [[ "${compl_func#_$namespace::}" == "$compl_func" ]]; then
-				local compl_wrapper="_${namespace}::${alias_name}"
+			if [[ "${compl_func#_"$namespace"::}" == "$compl_func" ]]; then
+				compl_wrapper="_${namespace}::${alias_name}"
 				echo "function $compl_wrapper {
                         local compl_word=\$2
                         local prec_word=\$3
diff --git a/plugins/available/autojump.plugin.bash b/plugins/available/autojump.plugin.bash
index 345ecadb5b..dc8fbbb49f 100644
--- a/plugins/available/autojump.plugin.bash
+++ b/plugins/available/autojump.plugin.bash
@@ -1,12 +1,15 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'Autojump configuration, see https://github.com/wting/autojump for more details'
 
 # Only supports the Homebrew variant, Debian and Arch at the moment.
 # Feel free to provide a PR to support other install locations
-if command -v brew &>/dev/null && [[ -s $(brew --prefix)/etc/profile.d/autojump.sh ]]; then
-  . $(brew --prefix)/etc/profile.d/autojump.sh
-elif command -v dpkg &>/dev/null && dpkg -s autojump &>/dev/null ; then
-  . "$(dpkg-query -S autojump.sh | cut -d' ' -f2)"
-elif command -v pacman &>/dev/null && pacman -Q autojump &>/dev/null ; then
-  . "$(pacman -Ql autojump | grep autojump.sh | cut -d' ' -f2)"
+if _bash_it_homebrew_check && [[ -s "${BASH_IT_HOMEBREW_PREFIX}/etc/profile.d/autojump.sh" ]]; then
+	source "${BASH_IT_HOMEBREW_PREFIX}/etc/profile.d/autojump.sh"
+elif _command_exists dpkg && dpkg -s autojump &> /dev/null; then
+	# shellcheck disable=SC1090
+	source "$(dpkg-query -S autojump.sh | cut -d' ' -f2)"
+elif _command_exists pacman && pacman -Q autojump &> /dev/null; then
+	# shellcheck disable=SC1090
+	source "$(pacman -Ql autojump | grep autojump.sh | cut -d' ' -f2)"
 fi
diff --git a/plugins/available/base.plugin.bash b/plugins/available/base.plugin.bash
old mode 100755
new mode 100644
index 6da1384edf..6490ab880b
--- a/plugins/available/base.plugin.bash
+++ b/plugins/available/base.plugin.bash
@@ -1,215 +1,180 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'miscellaneous tools'
 
-function ips ()
-{
-    about 'display all ip addresses for this host'
-    group 'base'
-    if command -v ifconfig &>/dev/null
-    then
-        ifconfig | awk '/inet /{ gsub(/addr:/, ""); print $2 }'
-    elif command -v ip &>/dev/null
-    then
-        ip addr | grep -oP 'inet \K[\d.]+'
-    else
-        echo "You don't have ifconfig or ip command installed!"
-    fi
+function ips() {
+	about 'display all ip addresses for this host'
+	group 'base'
+	if _command_exists ifconfig; then
+		ifconfig | awk '/inet /{ gsub(/addr:/, ""); print $2 }'
+	elif _command_exists ip; then
+		ip addr | grep -oP 'inet \K[\d.]+'
+	else
+		echo "You don't have ifconfig or ip command installed!"
+	fi
 }
 
-function down4me ()
-{
-    about 'checks whether a website is down for you, or everybody'
-    param '1: website url'
-    example '$ down4me http://www.google.com'
-    group 'base'
-    curl -Ls "http://downforeveryoneorjustme.com/$1" | sed '/just you/!d;s/<[^>]*>//g'
+function down4me() {
+	about 'checks whether a website is down for you, or everybody'
+	param '1: website url'
+	example '$ down4me http://www.google.com'
+	group 'base'
+	curl -Ls "http://downforeveryoneorjustme.com/$1" | sed '/just you/!d;s/<[^>]*>//g'
 }
 
-function myip ()
-{
-    about 'displays your ip address, as seen by the Internet'
-    group 'base'
-    list=("http://myip.dnsomatic.com/" "http://checkip.dyndns.com/" "http://checkip.dyndns.org/")
-    for url in ${list[*]}
-    do
-        res=$(curl -fs "${url}")
-        if [ $? -eq 0 ];then
-            break;
-        fi
-    done
-    res=$(echo "$res" | grep -Eo '[0-9\.]+')
-    echo -e "Your public IP is: ${echo_bold_green} $res ${echo_normal}"
+function myip() {
+	about 'displays your ip address, as seen by the Internet'
+	group 'base'
+	list=("http://myip.dnsomatic.com/" "http://checkip.dyndns.com/" "http://checkip.dyndns.org/")
+	for url in "${list[@]}"; do
+		if res="$(curl -fs "${url}")"; then
+			break
+		fi
+	done
+	res="$(echo "$res" | grep -Eo '[0-9\.]+')"
+	echo -e "Your public IP is: ${echo_bold_green-} $res ${echo_normal-}"
 }
 
-function pickfrom ()
-{
-    about 'picks random line from file'
-    param '1: filename'
-    example '$ pickfrom /usr/share/dict/words'
-    group 'base'
-    local file=$1
-    [ -z "$file" ] && reference $FUNCNAME && return
-    length=$(cat $file | wc -l)
-    n=$(expr $RANDOM \* $length \/ 32768 + 1)
-    head -n $n $file | tail -1
+function pickfrom() {
+	about 'picks random line from file'
+	param '1: filename'
+	example '$ pickfrom /usr/share/dict/words'
+	group 'base'
+	local file=${1:-}
+	local -i n=0 length
+	if [[ ! -r "$file" ]]; then
+		reference "${FUNCNAME[0]}" && return
+	fi
+	length="$(wc -l < "$file")"
+	n=$((RANDOM * length / 32768 + 1))
+	head -n "$n" "$file" | tail -1
 }
 
-function passgen ()
-{
-    about 'generates random password from dictionary words'
-    param 'optional integer length'
-    param 'if unset, defaults to 4'
-    example '$ passgen'
-    example '$ passgen 6'
-    group 'base'
-    local i pass length=${1:-4}
-    pass=$(echo $(for i in $(eval echo "{1..$length}"); do pickfrom /usr/share/dict/words; done))
-    echo "With spaces (easier to memorize): $pass"
-    echo "Without (use this as the password): $(echo $pass | tr -d ' ')"
+function passgen() {
+	about 'generates random password from dictionary words'
+	param 'optional integer length'
+	param 'if unset, defaults to 4'
+	example '$ passgen'
+	example '$ passgen 6'
+	group 'base'
+	local -i i length=${1:-4}
+	local pass
+	# shellcheck disable=SC2034
+	pass="$(for i in $(eval "echo {1..$length}"); do pickfrom /usr/share/dict/words; done)"
+	echo "With spaces (easier to memorize): ${pass//$'\n'/ }"
+	echo "Without spaces (easier to brute force): ${pass//$'\n'/}"
 }
 
 # Create alias pass to passgen when pass isn't installed or
 # BASH_IT_LEGACY_PASS is true.
-if ! command -v pass &>/dev/null || [ "$BASH_IT_LEGACY_PASS" = true ]
-then
-  alias pass=passgen
+if ! _command_exists pass || [[ "${BASH_IT_LEGACY_PASS:-}" = true ]]; then
+	alias pass=passgen
 fi
 
-function pmdown ()
-{
-    about 'preview markdown file in a browser'
-    param '1: markdown file'
-    example '$ pmdown README.md'
-    group 'base'
-    if command -v markdown &>/dev/null
-    then
-      markdown $1 | browser
-    else
-      echo "You don't have a markdown command installed!"
-    fi
-}
+if _command_exists markdown && _command_exists browser; then
+	function pmdown() {
+		about 'preview markdown file in a browser'
+		param '1: markdown file'
+		example '$ pmdown README.md'
+		group 'base'
 
-function mkcd ()
-{
-    about 'make one or more directories and cd into the last one'
-    param 'one or more directories to create'
-    example '$ mkcd foo'
-    example '$ mkcd /tmp/img/photos/large'
-    example '$ mkcd foo foo1 foo2 fooN'
-    example '$ mkcd /tmp/img/photos/large /tmp/img/photos/self /tmp/img/photos/Beijing'
-    group 'base'
-    mkdir -p -- "$@" && eval cd -- "\"\$$#\""
-}
+		markdown "${1?}" | browser
+	}
+fi
 
-function lsgrep ()
-{
-    about 'search through directory contents with grep'
-    group 'base'
-    ls | grep "$*"
+function mkcd() {
+	about 'make one or more directories and cd into the last one'
+	param 'one or more directories to create'
+	example '$ mkcd foo'
+	example '$ mkcd /tmp/img/photos/large'
+	example '$ mkcd foo foo1 foo2 fooN'
+	example '$ mkcd /tmp/img/photos/large /tmp/img/photos/self /tmp/img/photos/Beijing'
+	group 'base'
+	mkdir -p -- "$@" && cd -- "${!#}" || return
 }
 
-function quiet ()
-{
-    about 'what *does* this do?'
-    group 'base'
-    $* &> /dev/null &
+# shellcheck disable=SC2010
+function lsgrep() {
+	about 'search through directory contents with grep'
+	group 'base'
+	ls | grep "$@"
 }
 
-function banish-cookies ()
-{
-    about 'redirect .adobe and .macromedia files to /dev/null'
-    group 'base'
-    rm -r ~/.macromedia ~/.adobe
-    ln -s /dev/null ~/.adobe
-    ln -s /dev/null ~/.macromedia
+function quiet() {
+	about 'what *does* this do?'
+	group 'base'
+	nohup "$@" &> /dev/null < /dev/null &
 }
 
-function usage ()
-{
-    about 'disk usage per directory, in Mac OS X and Linux'
-    param '1: directory name'
-    group 'base'
-    if [ $(uname) = "Darwin" ]; then
-        if [ -n "$1" ]; then
-            du -hd 1 "$1"
-        else
-            du -hd 1
-        fi
-
-    elif [ $(uname) = "Linux" ]; then
-        if [ -n "$1" ]; then
-            du -h --max-depth=1 "$1"
-        else
-            du -h --max-depth=1
-        fi
-    fi
+function usage() {
+	about 'disk usage per directory, in Mac OS X and Linux'
+	param '1: directory name'
+	group 'base'
+	case $OSTYPE in
+		*'darwin'*)
+			du -hd 1 "$@"
+			;;
+		*'linux'*)
+			du -h --max-depth=1 "$@"
+			;;
+	esac
 }
 
-if [ ! -e "${BASH_IT}/plugins/enabled/todo.plugin.bash" ] && [ ! -e "${BASH_IT}/plugins/enabled/*${BASH_IT_LOAD_PRIORITY_SEPARATOR}todo.plugin.bash" ]; then
-# if user has installed todo plugin, skip this...
-    function t ()
-    {
-        about 'one thing todo'
-        param 'if not set, display todo item'
-        param '1: todo text'
-        if [[ "$*" == "" ]] ; then
-            cat ~/.t
-        else
-            echo "$*" > ~/.t
-        fi
-    }
+# shellcheck disable=SC2144 # the glob matches only one file
+if [[ ! -e "${BASH_IT?}/plugins/enabled/todo.plugin.bash" &&
+	! -e "${BASH_IT?}/plugins/enabled"/*"${BASH_IT_LOAD_PRIORITY_SEPARATOR-}todo.plugin.bash" ]]; then
+	# if user has installed todo plugin, skip this...
+	function t() {
+		about 'one thing todo'
+		param 'if not set, display todo item'
+		param '1: todo text'
+		if [[ "$*" == "" ]]; then
+			cat ~/.t
+		else
+			echo "$*" > ~/.t
+		fi
+	}
 fi
 
-function command_exists ()
-{
-    about 'checks for existence of a command'
-    param '1: command to check'
-    example '$ command_exists ls && echo exists'
-    group 'base'
-    type "$1" &> /dev/null ;
-}
-
-mkiso ()
-{
-    about 'creates iso from current dir in the parent dir (unless defined)'
-    param '1: ISO name'
-    param '2: dest/path'
-    param '3: src/path'
-    example 'mkiso'
-    example 'mkiso ISO-Name dest/path src/path'
-    group 'base'
-
-    if type "mkisofs" > /dev/null; then
-        [ -z ${1+x} ] && local isoname=${PWD##*/} || local isoname=$1
-        [ -z ${2+x} ] && local destpath=../ || local destpath=$2
-        [ -z ${3+x} ] && local srcpath=${PWD} || local srcpath=$3
-
-        if [ ! -f "${destpath}${isoname}.iso" ]; then
-            echo "writing ${isoname}.iso to ${destpath} from ${srcpath}"
-            mkisofs -V ${isoname} -iso-level 3 -r -o "${destpath}${isoname}.iso" "${srcpath}"
-        else
-            echo "${destpath}${isoname}.iso already exists"
-        fi
-    else
-        echo "mkisofs cmd does not exist, please install cdrtools"
-    fi
-}
+if _command_exists mkisofs; then
+	function mkiso() {
+		about 'creates iso from current dir in the parent dir (unless defined)'
+		param '1: ISO name'
+		param '2: dest/path'
+		param '3: src/path'
+		example 'mkiso'
+		example 'mkiso ISO-Name dest/path src/path'
+		group 'base'
+
+		local isoname="${1:-${PWD##*/}}"
+		local destpath="${2:-../}"
+		local srcpath="${3:-${PWD}}"
+
+		if [[ ! -f "${destpath%/}/${isoname}.iso" ]]; then
+			echo "writing ${isoname}.iso to ${destpath} from ${srcpath}"
+			mkisofs -V "${isoname}" -iso-level 3 -r -o "${destpath%/}/${isoname}.iso" "${srcpath}"
+		else
+			echo "${destpath%/}/${isoname}.iso already exists"
+		fi
+	}
+fi
 
 # useful for administrators and configs
-function buf ()
-{
-    about 'back up file with timestamp'
-    param 'filename'
-    group 'base'
-    local filename=$1
-    local filetime=$(date +%Y%m%d_%H%M%S)
-    cp -a "${filename}" "${filename}_${filetime}"
+function buf() {
+	about 'back up file with timestamp'
+	param 'filename'
+	group 'base'
+	local filename="${1?}" filetime
+	filetime=$(date +%Y%m%d_%H%M%S)
+	cp -a "${filename}" "${filename}_${filetime}"
 }
 
-function del() {
-    about 'move files to hidden folder in tmp, that gets cleared on each reboot'
-    param 'file or folder to be deleted'
-    example 'del ./file.txt'
-    group 'base'
-    mkdir -p /tmp/.trash && mv "$@" /tmp/.trash;
-}
+if ! _command_exists del; then
+	function del() {
+		about 'move files to hidden folder in tmp, that gets cleared on each reboot'
+		param 'file or folder to be deleted'
+		example 'del ./file.txt'
+		group 'base'
+		mkdir -p /tmp/.trash && mv "$@" /tmp/.trash
+	}
+fi
diff --git a/plugins/available/blesh.plugin.bash b/plugins/available/blesh.plugin.bash
new file mode 100644
index 0000000000..7b1ce74e68
--- /dev/null
+++ b/plugins/available/blesh.plugin.bash
@@ -0,0 +1,19 @@
+# shellcheck shell=bash
+cite about-plugin
+about-plugin 'load ble.sh, the Bash line editor!'
+
+if [[ ${BLE_VERSION-} ]]; then
+	_log_warning "ble.sh is already loaded!"
+	return
+fi
+
+_bash_it_ble_path=${XDG_DATA_HOME:-$HOME/.local/share}/blesh/ble.sh
+if [[ -f $_bash_it_ble_path ]]; then
+	# shellcheck disable=1090
+	source "$_bash_it_ble_path"
+else
+	_log_error "Could not find ble.sh in $_bash_it_ble_path"
+	_log_error "Please install using the following command:"
+	_log_error "git clone https://github.com/akinomyoga/ble.sh && make -C ble.sh install"
+fi
+unset _bash_it_ble_path
diff --git a/plugins/available/boot2docker.plugin.bash b/plugins/available/boot2docker.plugin.bash
index c8b389c35c..f19e91ef84 100644
--- a/plugins/available/boot2docker.plugin.bash
+++ b/plugins/available/boot2docker.plugin.bash
@@ -3,7 +3,7 @@ about-plugin 'Helpers to get Docker setup correctly for boot2docker'
 
 # Note, this might need to be different if you have an older version
 # of boot2docker, or its configured for a different IP
-if [[ `uname -s` == "Darwin" ]]; then
+if [[ "$OSTYPE" == 'darwin'* ]]; then
   export DOCKER_HOST="tcp://192.168.59.103:2376"
   export DOCKER_CERT_PATH="~/.boot2docker/certs/boot2docker-vm"
   export DOCKER_TLS_VERIFY=1
diff --git a/plugins/available/cmd-returned-notify.plugin.bash b/plugins/available/cmd-returned-notify.plugin.bash
index a305087553..d9be5e4e9f 100644
--- a/plugins/available/cmd-returned-notify.plugin.bash
+++ b/plugins/available/cmd-returned-notify.plugin.bash
@@ -9,7 +9,7 @@ precmd_return_notification() {
 }
 
 preexec_return_notification() {
-	[ -z "${LAST_COMMAND_TIME}" ] && export LAST_COMMAND_TIME=$(date +%s)
+	[[ -z "${LAST_COMMAND_TIME}" ]] && LAST_COMMAND_TIME=$(date +%s)
 }
 
 precmd_functions+=(precmd_return_notification)
diff --git a/plugins/available/direnv.plugin.bash b/plugins/available/direnv.plugin.bash
index 5fd564f53c..62788600be 100644
--- a/plugins/available/direnv.plugin.bash
+++ b/plugins/available/direnv.plugin.bash
@@ -1,4 +1,7 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load direnv, if you are using it: https://direnv.net/'
 
-[ -x "$(which direnv)" ] && eval "$(direnv hook bash)"
+if _command_exists direnv; then
+	eval "$(direnv hook bash)"
+fi
diff --git a/plugins/available/dirs.plugin.bash b/plugins/available/dirs.plugin.bash
index c215f7ecf7..2c1adf7add 100644
--- a/plugins/available/dirs.plugin.bash
+++ b/plugins/available/dirs.plugin.bash
@@ -23,7 +23,7 @@ alias 8="pushd +8"
 alias 9="pushd +9"
 
 # Clone this location
-alias pc="pushd \$(pwd)"
+alias pc='pushd "${PWD}"'
 
 # Push new location
 alias pu="pushd"
@@ -73,7 +73,7 @@ G () {
     example '$ G ..'
     group 'dirs'
 
-    cd "${1:-$(pwd)}" ;
+    cd "${1:-${PWD}}" ;
 }
 
 S () {
@@ -86,7 +86,7 @@ S () {
 
     sed "/$@/d" ~/.dirs > ~/.dirs1;
     \mv ~/.dirs1 ~/.dirs;
-    echo "$@"=\"`pwd`\" >> ~/.dirs;
+    echo "$@"=\""${PWD}"\" >> ~/.dirs;
     source ~/.dirs ;
 }
 
diff --git a/plugins/available/git.plugin.bash b/plugins/available/git.plugin.bash
index e4efc3fe38..3a130955c1 100644
--- a/plugins/available/git.plugin.bash
+++ b/plugins/available/git.plugin.bash
@@ -2,12 +2,13 @@
 cite about-plugin
 about-plugin 'git helper functions'
 
+# shellcheck disable=SC2016
 function git_remote {
-	about "adds remote $GIT_HOSTING:$1 to current repo"
+	about 'adds remote $GIT_HOSTING:$1 to current repo'
 	group "git"
 
-	echo "Running: git remote add origin ${GIT_HOSTING}:$1.git"
-	git remote add origin "$GIT_HOSTING:$1".git
+	echo "Running: git remote add origin ${GIT_HOSTING:?}:$1.git"
+	git remote add origin "${GIT_HOSTING}:${1}".git
 }
 
 function git_first_push {
@@ -24,14 +25,14 @@ function git_pub() {
 	BRANCH=$(git rev-parse --abbrev-ref HEAD)
 
 	echo "Publishing ${BRANCH} to remote origin"
-	git push -u origin "$BRANCH"
+	git push -u origin "${BRANCH}"
 }
 
 function git_revert() {
 	about 'applies changes to HEAD that revert all changes after this commit'
 	group 'git'
 
-	git reset "$1"
+	git reset "${1:?}"
 	git reset --soft "HEAD@{1}"
 	git commit -m "Revert to ${1}"
 	git reset --hard
@@ -49,9 +50,7 @@ function git_rollback() {
 	}
 
 	function commit_exists() {
-		git rev-list --quiet "$1"
-		status=$?
-		if [ $status -ne 0 ]; then
+		if git rev-list --quiet "${1:?}"; then
 			echo "Commit ${1} does not exist"
 			kill -INT $$
 		fi
@@ -61,7 +60,7 @@ function git_rollback() {
 		while true; do
 			# shellcheck disable=SC2162
 			read -p "Do you want to keep all changes from rolled back revisions in your working tree? [Y/N]" RESP
-			case $RESP in
+			case "${RESP}" in
 
 				[yY])
 					echo "Rolling back to commit ${1} with unstaged changes"
@@ -87,7 +86,7 @@ function git_rollback() {
 		while true; do
 			# shellcheck disable=SC2162
 			read -p "WARNING: This will change your history and move the current HEAD back to commit ${1}, continue? [Y/N]" RESP
-			case $RESP in
+			case "${RESP}" in
 
 				[yY])
 					keep_changes "$1"
@@ -134,8 +133,8 @@ function git_info() {
 
 		# print all remotes and thier details
 		for remote in $(git remote show); do
-			echo "$remote":
-			git remote show "$remote"
+			echo "${remote}":
+			git remote show "${remote}"
 			echo
 		done
 
@@ -172,32 +171,32 @@ function git_stats {
 		AUTHORS=$(git shortlog -sn --all | cut -f2 | cut -f1 -d' ')
 		LOGOPTS=""
 		if [ "$1" == '-w' ]; then
-			LOGOPTS="$LOGOPTS -w"
+			LOGOPTS="${LOGOPTS} -w"
 			shift
 		fi
 		if [ "$1" == '-M' ]; then
-			LOGOPTS="$LOGOPTS -M"
+			LOGOPTS="${LOGOPTS} -M"
 			shift
 		fi
 		if [ "$1" == '-C' ]; then
-			LOGOPTS="$LOGOPTS -C --find-copies-harder"
+			LOGOPTS="${LOGOPTS} -C --find-copies-harder"
 			shift
 		fi
-		for a in $AUTHORS; do
+		for a in ${AUTHORS}; do
 			echo '-------------------'
-			echo "Statistics for: $a"
+			echo "Statistics for: ${a}"
 			echo -n "Number of files changed: "
 			# shellcheck disable=SC2086
-			git log $LOGOPTS --all --numstat --format="%n" --author="$a" | cut -f3 | sort -iu | wc -l
+			git log ${LOGOPTS} --all --numstat --format="%n" --author="${a}" | cut -f3 | sort -iu | wc -l
 			echo -n "Number of lines added: "
 			# shellcheck disable=SC2086
-			git log $LOGOPTS --all --numstat --format="%n" --author="$a" | cut -f1 | awk '{s+=$1} END {print s}'
+			git log ${LOGOPTS} --all --numstat --format="%n" --author="${a}" | cut -f1 | awk '{s+=$1} END {print s}'
 			echo -n "Number of lines deleted: "
 			# shellcheck disable=SC2086
-			git log $LOGOPTS --all --numstat --format="%n" --author="$a" | cut -f2 | awk '{s+=$1} END {print s}'
+			git log ${LOGOPTS} --all --numstat --format="%n" --author="${a}" | cut -f2 | awk '{s+=$1} END {print s}'
 			echo -n "Number of merges: "
 			# shellcheck disable=SC2086
-			git log $LOGOPTS --all --merges --author="$a" | grep -c '^commit'
+			git log ${LOGOPTS} --all --merges --author="${a}" | grep -c '^commit'
 		done
 	else
 		echo "you're currently not in a git repository"
@@ -212,18 +211,16 @@ function gittowork() {
 
 	result=$(curl -L "https://www.gitignore.io/api/$1" 2> /dev/null)
 
-	if [[ $result =~ ERROR ]]; then
+	if [[ "${result}" =~ ERROR ]]; then
 		echo "Query '$1' has no match. See a list of possible queries with 'gittowork list'"
-	elif [[ $1 = list ]]; then
-		echo "$result"
+	elif [[ $1 == list ]]; then
+		echo "${result}"
 	else
 		if [[ -f .gitignore ]]; then
-			result=$(echo "$result" | grep -v "# Created by http://www.gitignore.io")
+			result=$(grep -v "# Created by http://www.gitignore.io" <<< "${result}")
 			echo ".gitignore already exists, appending..."
-			echo "$result" >> .gitignore
-		else
-			echo "$result" > .gitignore
 		fi
+		echo "${result}" >> .gitignore
 	fi
 }
 
@@ -257,7 +254,7 @@ function gitignore-reload() {
 	fi
 
 	# Prompt user to commit or stash changes and exit
-	if [ $err = 1 ]; then
+	if [[ "${err}" == 1 ]]; then
 		echo >&2 "Please commit or stash them."
 	fi
 
@@ -265,7 +262,7 @@ function gitignore-reload() {
 
 	# If we're here, then there are no uncommited or unstaged changes dangling around.
 	# Proceed to reload .gitignore
-	if [ $err = 0 ]; then
+	if [[ "${err}" == 0 ]]; then
 		# Remove all cached files
 		git rm -r --cached .
 
@@ -290,6 +287,7 @@ function git-changelog() {
 		return 1
 	fi
 
+	# shellcheck disable=SC2155
 	local NEXT=$(date +%F)
 
 	if [[ "$2" == "md" ]]; then
@@ -298,9 +296,9 @@ function git-changelog() {
 		# shellcheck disable=SC2162
 		git log "$1" --no-merges --format="%cd" --date=short | sort -u -r | while read DATE; do
 			echo
-			echo "### $DATE"
-			git log --no-merges --format=" * (%h) %s by [%an](mailto:%ae)" --since="$DATE 00:00:00" --until="$DATE 24:00:00"
-			NEXT=$DATE
+			echo "### ${DATE}"
+			git log --no-merges --format=" * (%h) %s by [%an](mailto:%ae)" --since="${DATE} 00:00:00" --until="${DATE} 24:00:00"
+			NEXT=${DATE}
 		done
 	else
 		echo "CHANGELOG $1"
@@ -309,9 +307,10 @@ function git-changelog() {
 		# shellcheck disable=SC2162
 		git log "$1" --no-merges --format="%cd" --date=short | sort -u -r | while read DATE; do
 			echo
-			echo [$DATE]
-			git log --no-merges --format=" * (%h) %s by %an <%ae>" --since="$DATE 00:00:00" --until="$DATE 24:00:00"
-			NEXT=$DATE
+			echo "[${DATE}]"
+			git log --no-merges --format=" * (%h) %s by %an <%ae>" --since="${DATE} 00:00:00" --until="${DATE} 24:00:00"
+			# shellcheck disable=SC2034
+			NEXT=${DATE}
 		done
 	fi
 }
diff --git a/plugins/available/goenv.plugin.bash b/plugins/available/goenv.plugin.bash
index d00fce67a3..17e4a0ffd3 100644
--- a/plugins/available/goenv.plugin.bash
+++ b/plugins/available/goenv.plugin.bash
@@ -30,7 +30,7 @@ eval "$(goenv init - bash)"
 # If moving to a directory with a goenv version set, reload the shell
 # to ensure the shell environment matches expectations.
 _bash-it-goenv-preexec() {
-	export GOENV_OLD_VERSION="$(goenv version-name)"
+	GOENV_OLD_VERSION="$(goenv version-name)"
 }
 _bash-it-goenv-precmd() {
 	if [[ -n $GOENV_OLD_VERSION ]] && [[ "$GOENV_OLD_VERSION" != "$(goenv version-name)" ]]; then
diff --git a/plugins/available/gradle.plugin.bash b/plugins/available/gradle.plugin.bash
index 6267bd842d..8dec1313e7 100644
--- a/plugins/available/gradle.plugin.bash
+++ b/plugins/available/gradle.plugin.bash
@@ -3,19 +3,10 @@ about-plugin 'Add a gw command to use gradle wrapper if present, else use system
 
 function gw() {
   local file="gradlew"
-  local curr_path="${PWD}"
-  local result="gradle"
+  local result
 
-  # Search recursively upwards for file.
-  until [[ "${curr_path}" == "/" ]]; do
-    if [[ -e "${curr_path}/${file}" ]]; then
-      result="${curr_path}/${file}"
-      break
-    else
-      curr_path=$(dirname "${curr_path}")
-    fi
-  done
+  result="$(_bash-it-find-in-ancestor "${file}")"
 
   # Call gradle
-  "${result}" $*
+  "${result:-gradle}" $*
 }
diff --git a/plugins/available/hub.plugin.bash b/plugins/available/hub.plugin.bash
index 0a67a7af08..e9a8cbab48 100644
--- a/plugins/available/hub.plugin.bash
+++ b/plugins/available/hub.plugin.bash
@@ -1,4 +1,7 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load hub, if you are using it'
 
-command -v hub &> /dev/null && eval "$(hub alias -s)"
+if _command_exists hub; then
+	eval "$(hub alias -s)"
+fi
diff --git a/plugins/available/jekyll.plugin.bash b/plugins/available/jekyll.plugin.bash
index 6254a87fed..c340c432cd 100644
--- a/plugins/available/jekyll.plugin.bash
+++ b/plugins/available/jekyll.plugin.bash
@@ -16,7 +16,7 @@ editpost() {
 
   for site in ${SITES[@]}
   do
-    if [ "$(basename $site)" = "$1" ]
+    if [ "${site##*/}" = "$1" ]
     then
       SITE=$site
       break
@@ -77,7 +77,7 @@ newpost() {
 
   for site in ${SITES[@]}
   do
-    if [ "$(basename $site)" = "$1" ]
+    if [ "${site##*/}" = "$1" ]
     then
       SITE=$site
       JEKYLL_FORMATTING=${MARKUPS[$loc]}
@@ -280,7 +280,7 @@ function testsite() {
 
   for site in ${SITES[@]}
   do
-    if [ "$(basename $site)" = "$1" ]
+    if [ "${site##*/}" = "$1" ]
     then
       SITE=$site
       break
@@ -312,7 +312,7 @@ function buildsite() {
 
   for site in ${SITES[@]}
   do
-    if [ "$(basename $site)" = "$1" ]
+    if [ "${site##*/}" = "$1" ]
     then
       SITE=$site
       break
@@ -347,7 +347,7 @@ function deploysite() {
 
   for site in ${SITES[@]}
   do
-    if [ "$(basename $site)" = "$1" ]
+    if [ "${site##*/}" = "$1" ]
     then
       SITE=$site
       REMOTE=${REMOTES[$loc]}
diff --git a/plugins/available/jump.plugin.bash b/plugins/available/jump.plugin.bash
old mode 100755
new mode 100644
index 26d6467d31..1713d1b703
--- a/plugins/available/jump.plugin.bash
+++ b/plugins/available/jump.plugin.bash
@@ -1,9 +1,12 @@
+# shellcheck shell=bash
+# shellcheck disable=SC2016
 cite about-plugin
 about-plugin 'initialize jump (see https://github.com/gsamokovarov/jump). Add `export JUMP_OPTS=("--bind=z")` to change keybinding'
 
-__init_jump() {
-  command -v jump &> /dev/null || return
-  eval "$(jump shell bash "${JUMP_OPTS[@]}")"
+function __init_jump() {
+	if _command_exists jump; then
+		eval "$(jump shell bash "${JUMP_OPTS[@]}")"
+	fi
 }
 
 __init_jump
diff --git a/plugins/available/less-pretty-cat.plugin.bash b/plugins/available/less-pretty-cat.plugin.bash
index b6b9d1f05b..139e518819 100644
--- a/plugins/available/less-pretty-cat.plugin.bash
+++ b/plugins/available/less-pretty-cat.plugin.bash
@@ -1,31 +1,23 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'pygmentize instead of cat to terminal if possible'
 
-if $(command -v pygmentize &> /dev/null) ; then
-  # get the full paths to binaries
-  CAT_BIN=$(which cat)
-  LESS_BIN=$(which less)
-  BASH_IT_CCAT_STYLE="${BASH_IT_CCAT_STYLE:=default}"
-  BASH_IT_CLESS_STYLE="${BASH_IT_CLESS_STYLE:=default}"
+_command_exists pygmentize || return
 
-  # pigmentize cat and less outputs - call them ccat and cless to avoid that
-  # especially cat'ed output in scripts gets mangled with pygemtized meta characters
-  function ccat()
-  {
-      about 'runs either pygmentize or cat on each file passed in'
-      param '*: files to concatenate (as normally passed to cat)'
-      example 'cat mysite/manage.py dir/text-file.txt'
-      for var;
-      do
-          pygmentize -f 256 -O style="$BASH_IT_CCAT_STYLE" -g "$var" 2>/dev/null || "$CAT_BIN" "$var";
-      done
-  }
+# pigmentize cat and less outputs - call them ccat and cless to avoid that
+# especially cat'ed output in scripts gets mangled with pygemtized meta characters
+function ccat() {
+	about 'runs pygmentize on each file passed in'
+	param '*: files to concatenate (as normally passed to cat)'
+	example 'ccat mysite/manage.py dir/text-file.txt'
 
-  function cless()
-  {
-      about 'it pigments the file passed in and passes it to less for pagination'
-      param '$1: the file to paginate with less'
-      example 'less mysite/manage.py'
-      pygmentize -f 256 -O style="$BASH_IT_CLESS_STYLE" -g $* | "$LESS_BIN" -R
-  }
-fi
+	pygmentize -f 256 -O style="${BASH_IT_CCAT_STYLE:-default}" -g "$@"
+}
+
+function cless() {
+	about 'pigments the files passed in and passes to less for pagination'
+	param '*: the files to paginate with less'
+	example 'cless mysite/manage.py'
+
+	pygmentize -f 256 -O style="${BASH_IT_CLESS_STYLE:-default}" -g "$@" | command less -R
+}
diff --git a/plugins/available/node.plugin.bash b/plugins/available/node.plugin.bash
index 65df3da310..8bf876df24 100644
--- a/plugins/available/node.plugin.bash
+++ b/plugins/available/node.plugin.bash
@@ -1,13 +1,14 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'Node.js helper functions'
 
+# Check that we have npm
+_command_exists npm || return
+
 # Ensure local modules are preferred in PATH
 pathmunge "./node_modules/.bin" "after"
 
-# Check that we have npm
-out=$(command -v npm 2>&1) || return
-
 # If not using nodenv, ensure global modules are in PATH
-if [[ ! $out == *"nodenv/shims"* ]] ; then
-  pathmunge "$(npm config get prefix)/bin" "after"
+if [[ ! "$(type -p npm)" == *"nodenv/shims"* ]]; then
+	pathmunge "$(npm config get prefix)/bin" "after"
 fi
diff --git a/plugins/available/nodenv.plugin.bash b/plugins/available/nodenv.plugin.bash
index 1bbe7fbde7..262a57c399 100644
--- a/plugins/available/nodenv.plugin.bash
+++ b/plugins/available/nodenv.plugin.bash
@@ -1,7 +1,10 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load nodenv, if you are using it'
 
 export NODENV_ROOT="$HOME/.nodenv"
 pathmunge "$NODENV_ROOT/bin"
 
-[[ `which nodenv` ]] && eval "$(nodenv init - bash)"
+if _command_exists nodenv; then
+	eval "$(nodenv init - bash)"
+fi
diff --git a/plugins/available/nvm.plugin.bash b/plugins/available/nvm.plugin.bash
index e845d9229b..0e6da5d8cf 100644
--- a/plugins/available/nvm.plugin.bash
+++ b/plugins/available/nvm.plugin.bash
@@ -1,22 +1,23 @@
-# Bash-it no longer bundles nvm, as this was quickly becoming outdated.
+# shellcheck shell=bash
 #
 # BASH_IT_LOAD_PRIORITY: 225
 #
+# Bash-it no longer bundles nvm, as this was quickly becoming outdated.
 # Please install nvm from https://github.com/creationix/nvm.git if you want to use it.
 
 cite about-plugin
 about-plugin 'node version manager configuration'
 
-export NVM_DIR=${NVM_DIR:-$HOME/.nvm}
+export NVM_DIR="${NVM_DIR:-$HOME/.nvm}"
 # This loads nvm
-if command -v brew &>/dev/null && [ -s $(brew --prefix nvm)/nvm.sh ]
+if _bash_it_homebrew_check && [[ -s "${BASH_IT_HOMEBREW_PREFIX}/nvm.sh" ]]
 then
-  . $(brew --prefix nvm)/nvm.sh
+  source "${BASH_IT_HOMEBREW_PREFIX}/nvm.sh"
 else
-  [ -s "$NVM_DIR/nvm.sh" ] && . "$NVM_DIR/nvm.sh"
+  [[ -s "$NVM_DIR/nvm.sh" ]] && source "$NVM_DIR/nvm.sh"
 fi
 
-if ! command -v nvm &>/dev/null
+if ! _command_exists nvm
 then
   function nvm() {
     echo "Bash-it no longer bundles the nvm script. Please install the latest version from"
diff --git a/plugins/available/osx-timemachine.plugin.bash b/plugins/available/osx-timemachine.plugin.bash
index f29d6ece98..3d7ff00c92 100644
--- a/plugins/available/osx-timemachine.plugin.bash
+++ b/plugins/available/osx-timemachine.plugin.bash
@@ -15,7 +15,7 @@ function time-machine-list-machines() {
   local tmdest="$(time-machine-destination)/Backups.backupdb"
 
   find "$tmdest" -maxdepth 1 -mindepth 1 -type d | grep -v "/\." | while read line ; do
-    echo "$(basename "$line")"
+    echo "${line##*/}"
   done
 }
 
diff --git a/plugins/available/osx.plugin.bash b/plugins/available/osx.plugin.bash
index 2c16820c49..ca1f66b879 100644
--- a/plugins/available/osx.plugin.bash
+++ b/plugins/available/osx.plugin.bash
@@ -2,7 +2,7 @@ cite about-plugin
 about-plugin 'osx-specific functions'
 
 # OS X: Open new tabs in same directory
-if [ $(uname) = "Darwin" ]; then
+if [[ $OSTYPE == 'darwin'* ]]; then
   if type update_terminal_cwd > /dev/null 2>&1 ; then
     if ! [[ $PROMPT_COMMAND =~ (^|;)update_terminal_cwd($|;) ]] ; then
       PROMPT_COMMAND="${PROMPT_COMMAND%;};update_terminal_cwd"
@@ -46,13 +46,13 @@ function dock-switch() {
     example '$ dock-switch 2d'
     group 'osx'
 
-    if [ $(uname) = "Darwin" ]; then
+    if [[ "$OSTYPE" = 'darwin'* ]]; then
 
-        if [ $1 = 3d ] ; then
+        if [[ $1 = 3d ]] ; then
             defaults write com.apple.dock no-glass -boolean NO
             killall Dock
 
-        elif [ $1 = 2d ] ; then
+        elif [[ $1 = 2d ]] ; then
             defaults write com.apple.dock no-glass -boolean YES
             killall Dock
 
@@ -90,7 +90,7 @@ function prevcurl() {
   param '1: url'
   group 'osx'
 
-  if [ ! $(uname) = "Darwin" ]
+  if [[ ! $OSTYPE = 'darwin'* ]]
   then
     echo "This function only works with Mac OS X"
     return 1
@@ -103,7 +103,7 @@ function refresh-launchpad() {
   example '$ refresh-launchpad'
   group 'osx'
 
-  if [ $(uname) = "Darwin" ];then
+  if [[ "$OSTYPE" = 'darwin'* ]];then
     defaults write com.apple.dock ResetLaunchPad -bool TRUE
     killall Dock
   else
diff --git a/plugins/available/percol.plugin.bash b/plugins/available/percol.plugin.bash
index c1fc807cd7..027dfdc4af 100644
--- a/plugins/available/percol.plugin.bash
+++ b/plugins/available/percol.plugin.bash
@@ -1,3 +1,4 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'Search&Select history with percol'
 
@@ -12,24 +13,20 @@ about-plugin 'Search&Select history with percol'
 # Usage
 ## C-r to search&select from history
 
-_replace_by_history() {
-    if command -v tac>/dev/null; then
-        alias _tac=tac
-    else
-        alias _tac="tail -r"
-    fi
-    local l=$(HISTTIMEFORMAT= history | _tac | sed -e 's/^\ *[0-9]*\ *//' | percol --query "$READLINE_LINE")
-    READLINE_LINE="$l"
-    READLINE_POINT=${#l}
-}
-
+_command_exists percol || return
 
-if command -v percol>/dev/null; then
-    current_version=${BASH_VERSION%%[^0-9]*}
-    if [ $current_version -lt 4 ]; then
-       echo -e "\033[91mWarning: You have to upgrade Bash to Bash v4.x to use the 'percol' plugin.\033[m"
-       echo -e "\033[91m         Your current Bash version is $BASH_VERSION.\033[m"
-    else
-        bind -x '"\C-r": _replace_by_history'
-    fi
+if [[ ${BASH_VERSINFO[0]} -lt 4 ]]; then
+	_log_warning "You have to upgrade Bash to Bash v4.x to use the 'percol' plugin."
+	_log_warning "Your current Bash version is $BASH_VERSION."
+	return
 fi
+
+function _replace_by_history() {
+	local HISTTIMEFORMAT= # Ensure we can parse history properly
+	#TODO: "${histlines[@]/*( )+([[:digit:]])*( )/}"
+	local l
+	l="$(history | tail -r | sed -e 's/^\ *[0-9]*\ *//' | percol --query "${READLINE_LINE:-}")"
+	READLINE_LINE="${l}"
+	READLINE_POINT=${#l}
+}
+bind -x '"\C-r": _replace_by_history'
diff --git a/plugins/available/plenv.plugin.bash b/plugins/available/plenv.plugin.bash
index 1da2d61bfa..79a9cf4964 100644
--- a/plugins/available/plenv.plugin.bash
+++ b/plugins/available/plenv.plugin.bash
@@ -1,18 +1,16 @@
+# shellcheck shell=bash
+#
 # plugin for plenv
 
 cite about-plugin
 about-plugin 'plenv plugin for Perl'
 
-if [[ -e "${HOME}/.plenv/bin" ]] ; then
-
-  # load plenv bin dir into path if it exists
-  pathmunge "${HOME}/.plenv/bin"
-
+if [[ -d "${HOME}/.plenv/bin" ]]; then
+	# load plenv bin dir into path if it exists
+	pathmunge "${HOME}/.plenv/bin"
 fi
 
-if [[ `which plenv` ]] ; then
-
-  # init plenv
-  eval "$(plenv init - bash)"
-
+if _command_exists plenv; then
+	# init plenv
+	eval "$(plenv init - bash)"
 fi
diff --git a/plugins/available/powerline.plugin.bash b/plugins/available/powerline.plugin.bash
index 3d91e658ed..1927bf3e24 100644
--- a/plugins/available/powerline.plugin.bash
+++ b/plugins/available/powerline.plugin.bash
@@ -1,9 +1,9 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 cite about-plugin
 about-plugin 'enables powerline daemon'
 
-command -v powerline-daemon &>/dev/null || return
+_command_exists powerline-daemon || return
 powerline-daemon -q
 
 #the following should not be executed if bashit powerline themes in use
@@ -14,13 +14,13 @@ case "$BASH_IT_THEME" in
 esac
 POWERLINE_BASH_CONTINUATION=1
 POWERLINE_BASH_SELECT=1
-bashPowerlineInit=$(python -c \
+bashPowerlineInit="$(python -c \
 	"import os; \
 	import powerline;\
 	print(os.path.join(os.path.dirname(\
 	powerline.__file__),\
 	'bindings', \
 	'bash', \
-	'powerline.sh'))")
+	'powerline.sh'))")"
 [ -e $bashPowerlineInit ] || return
-. $bashPowerlineInit
+source $bashPowerlineInit
diff --git a/plugins/available/pyenv.plugin.bash b/plugins/available/pyenv.plugin.bash
index 4d8db4fb93..05d2847812 100644
--- a/plugins/available/pyenv.plugin.bash
+++ b/plugins/available/pyenv.plugin.bash
@@ -1,12 +1,34 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load pyenv, if you are using it'
 
-export PYENV_ROOT="$HOME/.pyenv"
-pathmunge "$PYENV_ROOT/bin"
+# https://github.com/pyenv/pyenv
 
-[[ `which pyenv 2>/dev/null` ]] && eval "$(pyenv init - bash)"
+# Load after basher
+# BASH_IT_LOAD_PRIORITY: 260
 
-#Load pyenv virtualenv if the virtualenv plugin is installed.
+# Don't modify the environment if we can't find the tool:
+# - Check if in $PATH already
+# - Check if installed manually to $PYENV_ROOT
+# - Check if installed manually to $HOME
+_command_exists pyenv \
+	|| [[ -n "$PYENV_ROOT" && -x "$PYENV_ROOT/bin/pyenv" ]] \
+	|| [[ -x "$HOME/.pyenv/bin/pyenv" ]] \
+	|| return 0
+
+# Set PYENV_ROOT, if not already set
+export PYENV_ROOT="${PYENV_ROOT:-$HOME/.pyenv}"
+
+# Add PYENV_ROOT/bin to PATH, if that's where it's installed
+if ! _command_exists pyenv && [[ -x "$PYENV_ROOT/bin/pyenv" ]]; then
+	pathmunge "$PYENV_ROOT/bin"
+fi
+
+# Initialize pyenv
+pathmunge "$PYENV_ROOT/shims"
+eval "$(pyenv init - bash)"
+
+# Load pyenv virtualenv if the virtualenv plugin is installed.
 if pyenv virtualenv-init - &> /dev/null; then
-  eval "$(pyenv virtualenv-init - bash)"
+	eval "$(pyenv virtualenv-init - bash)"
 fi
diff --git a/plugins/available/python.plugin.bash b/plugins/available/python.plugin.bash
index ceba6268b5..77fa7dd674 100644
--- a/plugins/available/python.plugin.bash
+++ b/plugins/available/python.plugin.bash
@@ -1,7 +1,7 @@
 cite about-plugin
 about-plugin 'alias "shttp" to SimpleHTTPServer'
 
-if [ $(uname) = "Linux" ]
+if [[ "$OSTYPE" == 'linux'* ]]
 then
   alias shttp='python2 -m SimpleHTTPServer'
 else
@@ -16,7 +16,7 @@ function pyedit() {
 
     xpyc=`python -c "import os, sys; f = open(os.devnull, 'w'); sys.stderr = f; module = __import__('$1'); sys.stdout.write(module.__file__)"`
 
-    if [ "$xpyc" == "" ]; then
+    if [[ "$xpyc" == "" ]]; then
         echo "Python module $1 not found"
         return -1
 
diff --git a/plugins/available/rbenv.plugin.bash b/plugins/available/rbenv.plugin.bash
index 2b01669de2..f3605f585c 100644
--- a/plugins/available/rbenv.plugin.bash
+++ b/plugins/available/rbenv.plugin.bash
@@ -1,7 +1,10 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'load rbenv, if you are using it'
 
 export RBENV_ROOT="$HOME/.rbenv"
 pathmunge "$RBENV_ROOT/bin"
 
-[[ `which rbenv 2>/dev/null` ]] && eval "$(rbenv init - bash)"
+if _command_exists rbenv; then
+	eval "$(rbenv init - bash)"
+fi
diff --git a/plugins/available/ruby.plugin.bash b/plugins/available/ruby.plugin.bash
index 4ab891d9f9..aed8daf8cd 100644
--- a/plugins/available/ruby.plugin.bash
+++ b/plugins/available/ruby.plugin.bash
@@ -1,16 +1,17 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'ruby and rubygems specific functions and settings'
 
 # Make commands installed with 'gem install --user-install' available
 # ~/.gem/ruby/${RUBY_VERSION}/bin/
-if which ruby >/dev/null && which gem >/dev/null; then
-  pathmunge "$(ruby -e 'print Gem.user_dir')/bin" after
+if _command_exists ruby && _command_exists gem; then
+	pathmunge "$(ruby -e 'print Gem.user_dir')/bin" after
 fi
 
-function remove_gem {
-  about 'removes installed gem'
-  param '1: installed gem name'
-  group 'ruby'
+function remove_gem() {
+	about 'removes installed gem'
+	param '1: installed gem name'
+	group 'ruby'
 
-  gem list | grep $1 | awk '{ print $1; }' | xargs sudo gem uninstall
+	gem list | grep "${1:?${FUNCNAME[0]}: no gem name provided}" | awk '{ print $1; }' | xargs sudo gem uninstall
 }
diff --git a/plugins/available/textmate.plugin.bash b/plugins/available/textmate.plugin.bash
index e3538c1e10..5c81f195ac 100644
--- a/plugins/available/textmate.plugin.bash
+++ b/plugins/available/textmate.plugin.bash
@@ -1,7 +1,9 @@
+# shellcheck shell=bash
 cite about-plugin
 about-plugin 'set textmate as a default editor'
 
-if $(command -v mate &> /dev/null) ; then
-  export EDITOR="$(which mate) -w"
-  export GIT_EDITOR=$EDITOR
+if _command_exists mate; then
+	EDITOR="$(type -p mate) -w"
+	GIT_EDITOR="$EDITOR"
+	export EDITOR GIT_EDITOR
 fi
diff --git a/plugins/available/todo.plugin.bash b/plugins/available/todo.plugin.bash
old mode 100755
new mode 100644
diff --git a/plugins/available/virtualenv.plugin.bash b/plugins/available/virtualenv.plugin.bash
index 468870cd4e..41d55ddfb1 100644
--- a/plugins/available/virtualenv.plugin.bash
+++ b/plugins/available/virtualenv.plugin.bash
@@ -1,12 +1,14 @@
+# shellcheck shell=bash
+#
 # make sure virtualenvwrapper is enabled if available
 
 cite about-plugin
 about-plugin 'virtualenvwrapper and pyenv-virtualenvwrapper helper functions'
 
 if _command_exists pyenv; then
-  pyenv virtualenvwrapper
-else
-  [[ `which virtualenvwrapper.sh` ]] && . virtualenvwrapper.sh
+	pyenv virtualenvwrapper
+elif _command_exists virtualenvwrapper.sh; then
+	source virtualenvwrapper.sh
 fi
 
 
@@ -14,8 +16,8 @@ function mkvenv {
   about 'create a new virtualenv for this directory'
   group 'virtualenv'
 
-  cwd=`basename \`pwd\``
-  mkvirtualenv --distribute $cwd
+  local cwd="${PWD##*/}"
+  mkvirtualenv --distribute "$cwd"
 }
 
 
@@ -23,19 +25,21 @@ function mkvbranch {
   about 'create a new virtualenv for the current branch'
   group 'virtualenv'
 
-  mkvirtualenv --distribute "$(basename `pwd`)@$SCM_BRANCH"
+  local cwd="${PWD##*/}"
+  mkvirtualenv --distribute "${cwd}@${SCM_BRANCH}"
 }
 
 function wovbranch {
   about 'sets workon branch'
   group 'virtualenv'
 
-  workon "$(basename `pwd`)@$SCM_BRANCH"
+  local cwd="${PWD##*/}"
+  workon "${cwd}@${SCM_BRANCH}"
 }
 
 function wovenv {
   about 'works on the virtualenv for this directory'
   group 'virtualenv'
 
-  workon "$(basename `pwd`)"
+  workon "${PWD##*/}"
 }
diff --git a/plugins/available/xterm.plugin.bash b/plugins/available/xterm.plugin.bash
index 4f4fd50d2d..b8747a2584 100644
--- a/plugins/available/xterm.plugin.bash
+++ b/plugins/available/xterm.plugin.bash
@@ -3,29 +3,37 @@ cite about-plugin
 about-plugin 'automatically set your xterm title with host and location info'
 
 _short-dirname() {
-	local dir_name=$(dirs +0)
-	[ "$SHORT_TERM_LINE" = true ] && [ "${#dir_name}" -gt 8 ] && echo "${dir_name##*/}" || echo "${dir_name}"
+	local dir_name="${PWD/~/\~}"
+	if [[ "${SHORT_TERM_LINE:-}" == true && "${#dir_name}" -gt 8 ]]; then
+		echo "${dir_name##*/}"
+	else
+		echo "${dir_name}"
+	fi
 }
 
 _short-command() {
 	local input_command="$*"
-	[ "$SHORT_TERM_LINE" = true ] && [ "${#input_command}" -gt 8 ] && echo "${input_command%% *}" || echo "${input_command}"
+	if [[ "${SHORT_TERM_LINE:-}" == true && "${#input_command}" -gt 8 ]]; then
+		echo "${input_command%% *}"
+	else
+		echo "${input_command}"
+	fi
 }
 
 set_xterm_title() {
-	local title="$1"
-	echo -ne "\033]0;$title\007"
+	local title="${1:-}"
+	echo -ne "\033]0;${title}\007"
 }
 
 precmd_xterm_title() {
-	set_xterm_title "${SHORT_USER:-${USER}}@${SHORT_HOSTNAME:-${HOSTNAME}} $(_short-dirname) $PROMPT_CHAR"
+	set_xterm_title "${SHORT_USER:-${USER}}@${SHORT_HOSTNAME:-${HOSTNAME}} $(_short-dirname) ${PROMPT_CHAR:-\$}"
 }
 
 preexec_xterm_title() {
-	set_xterm_title "$(_short-command "${1}") {$(_short-dirname)} (${SHORT_USER:-${USER}}@${SHORT_HOSTNAME:-${HOSTNAME}})"
+	set_xterm_title "$(_short-command "${1:-}") {$(_short-dirname)} (${SHORT_USER:-${USER}}@${SHORT_HOSTNAME:-${HOSTNAME}})"
 }
 
-case "$TERM" in
+case "${TERM:-dumb}" in
 	xterm* | rxvt*)
 		precmd_functions+=(precmd_xterm_title)
 		preexec_functions+=(preexec_xterm_title)
diff --git a/plugins/available/z_autoenv.plugin.bash b/plugins/available/z_autoenv.plugin.bash
index 553a7ba3ea..a2f97d2833 100644
--- a/plugins/available/z_autoenv.plugin.bash
+++ b/plugins/available/z_autoenv.plugin.bash
@@ -11,7 +11,7 @@ autoenv_init()
   typeset target home _file
   typeset -a _files
   target=$1
-  home="$(dirname "$HOME")"
+  home="${HOME%/*}"
 
   _files=( $(
     while [[ "$PWD" != "/" && "$PWD" != "$home" ]]
diff --git a/scripts/reloader.bash b/scripts/reloader.bash
old mode 100644
new mode 100755
index f22de67e81..4bc2494132
--- a/scripts/reloader.bash
+++ b/scripts/reloader.bash
@@ -5,6 +5,7 @@ function _set-prefix-based-on-path()
 {
   filename=$(_bash-it-get-component-name-from-path "$1")
   extension=$(_bash-it-get-component-type-from-path "$1")
+	# shellcheck disable=SC2034
   BASH_IT_LOG_PREFIX="$extension: $filename: "
 }
 
@@ -15,7 +16,7 @@ if [[ "$1" != "skip" ]] && [[ -d "$BASH_IT/enabled" ]]; then
     alias|completion|plugin)
       _bash_it_config_type=$1
       _log_debug "Loading enabled $1 components..." ;;
-    *|'')
+    ''|*)
       _log_debug "Loading all enabled components..." ;;
   esac
 
diff --git a/test/fixtures/svn/broken/xcrun b/test/fixtures/svn/broken/xcrun
new file mode 100755
index 0000000000..e69de29bb2
diff --git a/test/fixtures/svn/working/xcrun b/test/fixtures/svn/working/xcrun
new file mode 100755
index 0000000000..e69de29bb2
diff --git a/test/lib/helpers.bats b/test/lib/helpers.bats
index e60d5542ab..7f6664e04f 100644
--- a/test/lib/helpers.bats
+++ b/test/lib/helpers.bats
@@ -5,11 +5,11 @@ load "${BASH_IT}/vendor/github.com/erichs/composure/composure.sh"
 load ../../lib/log
 load ../../lib/utilities
 load ../../lib/search
-load ../../plugins/available/base.plugin
 
 cite _about _param _example _group _author _version
 
 load ../../lib/helpers
+load ../../plugins/available/base.plugin
 
 function local_setup {
   setup_test_fixture
diff --git a/test/lib/log.bats b/test/lib/log.bats
index 015068e68b..329386bd39 100644
--- a/test/lib/log.bats
+++ b/test/lib/log.bats
@@ -3,27 +3,28 @@
 load ../test_helper
 load "${BASH_IT}/vendor/github.com/erichs/composure/composure.sh"
 load ../../lib/appearance
-load ../../plugins/available/base.plugin
 
 cite _about _param _example _group _author _version
 load ../../lib/log
+load ../../lib/helpers
+load ../../plugins/available/base.plugin
 
 @test "lib log: basic debug logging with BASH_IT_LOG_LEVEL_ALL" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_ALL
   run _log_debug "test test test"
-  assert_output "DEBUG: test test test"
+  assert_output "DEBUG: default: test test test"
 }
 
 @test "lib log: basic warning logging with BASH_IT_LOG_LEVEL_ALL" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_ALL
   run _log_warning "test test test"
-  assert_output " WARN: test test test"
+  assert_output " WARN: default: test test test"
 }
 
 @test "lib log: basic error logging with BASH_IT_LOG_LEVEL_ALL" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_ALL
   run _log_error "test test test"
-  assert_output "ERROR: test test test"
+  assert_output "ERROR: default: test test test"
 }
 
 @test "lib log: basic debug logging with BASH_IT_LOG_LEVEL_WARNING" {
@@ -35,13 +36,13 @@ load ../../lib/log
 @test "lib log: basic warning logging with BASH_IT_LOG_LEVEL_WARNING" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_WARNING
   run _log_warning "test test test"
-  assert_output " WARN: test test test"
+  assert_output " WARN: default: test test test"
 }
 
 @test "lib log: basic error logging with BASH_IT_LOG_LEVEL_WARNING" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_WARNING
   run _log_error "test test test"
-  assert_output "ERROR: test test test"
+  assert_output "ERROR: default: test test test"
 }
 
 
@@ -60,7 +61,7 @@ load ../../lib/log
 @test "lib log: basic error logging with BASH_IT_LOG_LEVEL_ERROR" {
   BASH_IT_LOG_LEVEL=$BASH_IT_LOG_LEVEL_ERROR
   run _log_error "test test test"
-  assert_output "ERROR: test test test"
+  assert_output "ERROR: default: test test test"
 }
 
 @test "lib log: basic debug silent logging" {
diff --git a/test/plugins/base.plugin.bats b/test/plugins/base.plugin.bats
index 7daf26197f..6f1099cc08 100755
--- a/test/plugins/base.plugin.bats
+++ b/test/plugins/base.plugin.bats
@@ -2,6 +2,8 @@
 
 load ../test_helper
 load "${BASH_IT}/vendor/github.com/erichs/composure/composure.sh"
+load ../../lib/log
+load ../../lib/helpers
 load ../../plugins/available/base.plugin
 
 @test 'plugins base: ips()' {
@@ -40,7 +42,7 @@ load ../../plugins/available/base.plugin
   mkcd "${dir_name}"
   assert_success
   assert_dir_exist "${BASH_IT_ROOT}/${dir_name}"
-  assert_equal $(pwd) "${BASH_IT_ROOT}/${dir_name}"
+  assert_equal "${PWD}" "${BASH_IT_ROOT}/${dir_name}"
 }
 
 @test 'plugins base: lsgrep()' {
diff --git a/test/plugins/battery.plugin.bats b/test/plugins/battery.plugin.bats
old mode 100644
new mode 100755
index 9af49697fc..fda52b020d
--- a/test/plugins/battery.plugin.bats
+++ b/test/plugins/battery.plugin.bats
@@ -2,6 +2,8 @@
 
 load ../test_helper
 load "${BASH_IT}/vendor/github.com/erichs/composure/composure.sh"
+load "${BASH_IT}/lib/log.bash"
+load "${BASH_IT}/lib/helpers.bash"
 
 cite _about _param _example _group _author _version
 
diff --git a/test/plugins/go.plugin.bats b/test/plugins/go.plugin.bats
index c53f359f1f..110699e898 100644
--- a/test/plugins/go.plugin.bats
+++ b/test/plugins/go.plugin.bats
@@ -4,50 +4,52 @@ load ../test_helper
 load ../../lib/helpers
 load "${BASH_IT}/vendor/github.com/erichs/composure/composure.sh"
 
+# We test `go version` in each test to account for users with goenv and no system go.
+
 @test 'ensure _bash-it-gopath-pathmunge is defined' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   load ../../plugins/available/go.plugin
   run type -t _bash-it-gopath-pathmunge
   assert_line 'function'
 }
 
 @test 'plugins go: single entry in GOPATH' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1 <<<$PATH)" "/foo/bin"
 }
 
 @test 'plugins go: single entry in GOPATH, with space' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo bar"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1 <<<$PATH)" "/foo bar/bin"
 }
 
 @test 'plugins go: single entry in GOPATH, with escaped space' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo\ bar"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1 <<<$PATH)" "/foo\ bar/bin"
 }
 
 @test 'plugins go: multiple entries in GOPATH' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo:/bar"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1,2 <<<$PATH)" "/foo/bin:/bar/bin"
 }
 
 @test 'plugins go: multiple entries in GOPATH, with space' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo:/foo bar"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1,2 <<<$PATH)" "/foo/bin:/foo bar/bin"
 }
 
 @test 'plugins go: multiple entries in GOPATH, with escaped space' {
-  { [[ $CI ]] || _command_exists go; } || skip 'golang not found'
+  { _command_exists go && go version &>/dev/null; } || skip 'golang not found'
   export GOPATH="/foo:/foo\ bar"
   load ../../plugins/available/go.plugin
   assert_equal "$(cut -d':' -f1,2 <<<$PATH)" "/foo/bin:/foo\ bar/bin"
diff --git a/test/run b/test/run
index 8820291640..fe4ac8477d 100755
--- a/test/run
+++ b/test/run
@@ -6,7 +6,7 @@ git submodule init && git submodule update
 
 if [ -z "${BASH_IT}" ]; then
   declare BASH_IT
-  BASH_IT=$(cd ${test_directory} && dirname "$(pwd)")
+  BASH_IT="$(cd "${test_directory}" && dirname "${PWD}")"
   export BASH_IT
 fi
 
diff --git a/test/themes/base.theme.svn.bats b/test/themes/base.theme.svn.bats
index f2866c8da1..d1c2c31164 100644
--- a/test/themes/base.theme.svn.bats
+++ b/test/themes/base.theme.svn.bats
@@ -7,7 +7,6 @@ load ../../lib/log
 cite _about _param _example _group _author _version
 
 load ../../lib/helpers
-load ../../themes/base.theme
 
 function local_setup {
   setup_test_fixture
@@ -23,6 +22,8 @@ function local_setup {
   fi
 
   export OLD_PATH="$PATH"
+
+  load ../../themes/base.theme
 }
 
 function local_teardown {
@@ -56,8 +57,8 @@ function setup_svn_path {
 
   setup_svn_path "$BASH_IT/test/fixtures/svn/working"
 
-  # Load the base theme again so that the working SVN script is detected
-  load ../../themes/base.theme
+  # Init the base theme again so that the working SVN script is detected
+  _bash_it_appearance_scm_init
 
   scm
   # Make sure that the SVN command is used
@@ -73,8 +74,8 @@ function setup_svn_path {
 
   setup_svn_path "$BASH_IT/test/fixtures/svn/working"
 
-  # Load the base theme again so that the working SVN script is detected
-  load ../../themes/base.theme
+  # init the base theme again so that the working SVN script is detected
+  _bash_it_appearance_scm_init
 
   scm
   # Make sure that the SVN command is used
@@ -89,8 +90,8 @@ function setup_svn_path {
 
   setup_svn_path "$BASH_IT/test/fixtures/svn/working"
 
-  # Load the base theme again so that the working SVN script is detected
-  load ../../themes/base.theme
+  # Init the base theme again so that the working SVN script is detected
+  _bash_it_appearance_scm_init
 
   scm
   # Make sure that no SVN command is used
@@ -103,8 +104,8 @@ function setup_svn_path {
 
   setup_svn_path "$BASH_IT/test/fixtures/svn/broken"
 
-  # Load the base theme again so that the broken SVN script is detected
-  load ../../themes/base.theme
+  # Init the base theme again so that the broken SVN script is detected
+  _bash_it_appearance_scm_init
 
   scm
   # Make sure that no SVN command is not used
@@ -120,8 +121,8 @@ function setup_svn_path {
 
   setup_svn_path "$BASH_IT/test/fixtures/svn/broken"
 
-  # Load the base theme again so that the broken SVN script is detected
-  load ../../themes/base.theme
+  # Init the base theme again so that the broken SVN script is detected
+  _bash_it_appearance_scm_init
 
   scm
   # Make sure that no SVN command is used
diff --git a/themes/90210/90210.theme.bash b/themes/90210/90210.theme.bash
index 180764c869..3db3f17bae 100644
--- a/themes/90210/90210.theme.bash
+++ b/themes/90210/90210.theme.bash
@@ -1,4 +1,7 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
+
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
 SCM_THEME_PROMPT_PREFIX=" |"
@@ -11,7 +14,7 @@ GIT_THEME_PROMPT_SUFFIX="${green}|"
 
 # Nicely formatted terminal prompt
 function prompt_command() {
-	export PS1="\n${bold_black}[${blue}\@${bold_black}]-${bold_black}[${green}\u${yellow}@${green}\h${bold_black}]-${bold_black}[${purple}\w${bold_black}]-$(scm_prompt_info)\n${reset_color}\$ "
+	PS1="\n${bold_black}[${blue}\@${bold_black}]-${bold_black}[${green}\u${yellow}@${green}\h${bold_black}]-${bold_black}[${purple}\w${bold_black}]-$(scm_prompt_info)\n${reset_color}\$ "
 }
 
 safe_append_prompt_command prompt_command
diff --git a/themes/agnoster/agnoster.theme.bash b/themes/agnoster/agnoster.theme.bash
index ba3e2c9a84..20c184f382 100644
--- a/themes/agnoster/agnoster.theme.bash
+++ b/themes/agnoster/agnoster.theme.bash
@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 # vim: ft=bash ts=2 sw=2 sts=2
 #
 # agnoster's Theme - https://gist.github.com/3712874
@@ -220,7 +221,7 @@ prompt_virtualenv() {
 
 # Context: user@hostname (who am I and where am I)
 prompt_context() {
-	local user=$(whoami)
+	local user="${USER:-${LOGNAME:?}}"
 
 	if [[ $user != "$DEFAULT_USER" || -n $SSH_CLIENT ]]; then
 		prompt_segment black default "$user@\h"
diff --git a/themes/atomic/atomic.theme.bash b/themes/atomic/atomic.theme.bash
index 6bde68011d..03dc9e9562 100644
--- a/themes/atomic/atomic.theme.bash
+++ b/themes/atomic/atomic.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Atomic Bash Prompt for Bash-it
 # By lfelipe base on the theme brainy of MunifTanjim
diff --git a/themes/bakke/bakke.theme.bash b/themes/bakke/bakke.theme.bash
index 725350a036..d7bfbbe836 100644
--- a/themes/bakke/bakke.theme.bash
+++ b/themes/bakke/bakke.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
diff --git a/themes/barbuk/barbuk.theme.bash b/themes/barbuk/barbuk.theme.bash
index 8e09d4be3b..b614d148c1 100644
--- a/themes/barbuk/barbuk.theme.bash
+++ b/themes/barbuk/barbuk.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Theme custom glyphs
 SCM_GIT_CHAR_GITLAB=${BARBUK_GITLAB_CHAR:='  '}
diff --git a/themes/base.theme.bash b/themes/base.theme.bash
index a1520397eb..f9f5190d19 100644
--- a/themes/base.theme.bash
+++ b/themes/base.theme.bash
@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 
 CLOCK_CHAR_THEME_PROMPT_PREFIX=''
 CLOCK_CHAR_THEME_PROMPT_SUFFIX=''
@@ -85,42 +86,61 @@ RBENV_THEME_PROMPT_SUFFIX='|'
 RBFU_THEME_PROMPT_PREFIX=' |'
 RBFU_THEME_PROMPT_SUFFIX='|'
 
-GIT_EXE=$(which git 2> /dev/null || true)
-P4_EXE=$(which p4 2> /dev/null || true)
-HG_EXE=$(which hg 2> /dev/null || true)
-SVN_EXE=$(which svn 2> /dev/null || true)
-
-# Check for broken SVN exe that is caused by some versions of Xcode.
-# See https://github.com/Bash-it/bash-it/issues/1612 for more details.
-if [[ -x "$SVN_EXE" ]]; then
-	if ! "$SVN_EXE" --version > /dev/null 2>&1; then
-		# Unset the SVN exe variable so that SVN commands are avoided.
-		SVN_EXE=""
+: "${GIT_EXE:=$SCM_GIT}"
+: "${P4_EXE:=$SCM_P4}"
+: "${HG_EXE:=$SCM_HG}"
+: "${SVN_EXE:=$SCM_SVN}"
+
+function _bash_it_appearance_scm_init() {
+	GIT_EXE="$(type -P $SCM_GIT || true)"
+	P4_EXE="$(type -P $SCM_P4 || true)"
+	HG_EXE="$(type -P $SCM_HG || true)"
+	SVN_EXE="$(type -P $SCM_SVN || true)"
+
+	# Check for broken SVN exe that is caused by some versions of Xcode.
+	# See https://github.com/Bash-it/bash-it/issues/1612 for more details.
+	if [[ -x "$SVN_EXE" && -x "${SVN_EXE%/*}/xcrun" ]]; then
+		if ! "$SVN_EXE" --version > /dev/null 2>&1; then
+			# Unset the SVN exe variable so that SVN commands are avoided.
+			SVN_EXE=""
+		fi
 	fi
-fi
+}
+_bash_it_appearance_scm_init
 
 function scm {
 	if [[ "$SCM_CHECK" = false ]]; then
 		SCM=$SCM_NONE
 	elif [[ -f .git/HEAD ]] && [[ -x "$GIT_EXE" ]]; then
 		SCM=$SCM_GIT
-	elif [[ -x "$GIT_EXE" ]] && [[ -n "$(git rev-parse --is-inside-work-tree 2> /dev/null)" ]]; then
-		SCM=$SCM_GIT
-	elif [[ -x "$P4_EXE" ]] && [[ -n "$(p4 set P4CLIENT 2> /dev/null)" ]]; then
-		SCM=$SCM_P4
 	elif [[ -d .hg ]] && [[ -x "$HG_EXE" ]]; then
 		SCM=$SCM_HG
-	elif [[ -x "$HG_EXE" ]] && [[ -n "$(hg root 2> /dev/null)" ]]; then
-		SCM=$SCM_HG
 	elif [[ -d .svn ]] && [[ -x "$SVN_EXE" ]]; then
 		SCM=$SCM_SVN
+	elif [[ -x "$GIT_EXE" ]] && [[ -n "$(git rev-parse --is-inside-work-tree 2> /dev/null)" ]]; then
+		SCM=$SCM_GIT
+	elif [[ -x "$HG_EXE" ]] && [[ -n "$(hg root 2> /dev/null)" ]]; then
+		SCM=$SCM_HG
 	elif [[ -x "$SVN_EXE" ]] && [[ -n "$(svn info --show-item wc-root 2> /dev/null)" ]]; then
 		SCM=$SCM_SVN
+	elif [[ -x "$P4_EXE" ]] && [[ -n "$(p4 set P4CLIENT 2> /dev/null)" ]]; then
+		SCM=$SCM_P4
 	else
 		SCM=$SCM_NONE
 	fi
 }
 
+scm_prompt() {
+	local CHAR
+	CHAR="$(scm_char)"
+	local format=${SCM_PROMPT_FORMAT:-'[%s%s]'}
+
+	if [[ "${CHAR}" != "$SCM_NONE_CHAR" ]]; then
+		# shellcheck disable=2059
+		printf "$format\n" "$CHAR" "$(scm_prompt_info)"
+	fi
+}
+
 function scm_prompt_char {
 	if [[ -z $SCM ]]; then scm; fi
 	if [[ $SCM == "$SCM_GIT" ]]; then
@@ -332,15 +352,15 @@ function svn_prompt_vars {
 # - .hg is located in ~/Projects/Foo/.hg
 # - get_hg_root starts at ~/Projects/Foo/Bar and sees that there is no .hg directory, so then it goes into ~/Projects/Foo
 function get_hg_root {
-	local CURRENT_DIR=$(pwd)
+	local CURRENT_DIR="${PWD}"
 
-	while [ "$CURRENT_DIR" != "/" ]; do
-		if [ -d "$CURRENT_DIR/.hg" ]; then
+	while [[ "${CURRENT_DIR:-/}" != "/" ]]; do
+		if [[ -d "$CURRENT_DIR/.hg" ]]; then
 			echo "$CURRENT_DIR/.hg"
 			return
 		fi
 
-		CURRENT_DIR=$(dirname "$CURRENT_DIR")
+		CURRENT_DIR="${CURRENT_DIR%/*}"
 	done
 }
 
@@ -376,7 +396,7 @@ function hg_prompt_vars {
 
 function nvm_version_prompt {
 	local node
-	if declare -f -F nvm &> /dev/null; then
+	if _is_function nvm; then
 		node=$(nvm current 2> /dev/null)
 		[[ "${node}" == "system" ]] && return
 		echo -e "${NVM_THEME_PROMPT_PREFIX}${node}${NVM_THEME_PROMPT_SUFFIX}"
@@ -413,8 +433,8 @@ function rbfu_version_prompt {
 }
 
 function chruby_version_prompt {
-	if declare -f -F chruby &> /dev/null; then
-		if declare -f -F chruby_auto &> /dev/null; then
+	if _is_function chruby; then
+		if _is_function chruby_auto; then
 			chruby_auto
 		fi
 
@@ -437,6 +457,10 @@ function k8s_context_prompt {
 	echo -e "$(kubectl config current-context 2> /dev/null)"
 }
 
+function k8s_namespace_prompt {
+	echo -e "$(kubectl config view --minify --output 'jsonpath={..namespace}' 2> /dev/null)"
+}
+
 function virtualenv_prompt {
 	if [[ -n "$VIRTUAL_ENV" ]]; then
 		virtualenv=$(basename "$VIRTUAL_ENV")
@@ -528,7 +552,7 @@ function prompt_char {
 
 function battery_char {
 	if [[ "${THEME_BATTERY_PERCENTAGE_CHECK}" = true ]]; then
-		echo -e "${bold_red}$(battery_percentage)%"
+		echo -e "${bold_red:-}$(battery_percentage)%"
 	fi
 }
 
@@ -570,7 +594,7 @@ function __check_precmd_conflict() {
 function safe_append_prompt_command {
 	local prompt_re
 
-	if [ "${__bp_imported}" == "defined" ]; then
+	if [ "${__bp_imported:-missing}" == "defined" ]; then
 		# We are using bash-preexec
 		if ! __check_precmd_conflict "${1}"; then
 			precmd_functions+=("${1}")
@@ -585,7 +609,7 @@ function safe_append_prompt_command {
 			prompt_re="\<${1}\>"
 		fi
 
-		if [[ ${PROMPT_COMMAND} =~ ${prompt_re} ]]; then
+		if [[ ${PROMPT_COMMAND[*]:-} =~ ${prompt_re} ]]; then
 			return
 		elif [[ -z ${PROMPT_COMMAND} ]]; then
 			PROMPT_COMMAND="${1}"
diff --git a/themes/binaryanomaly/binaryanomaly.theme.bash b/themes/binaryanomaly/binaryanomaly.theme.bash
index f6740f351d..c4488c4c96 100644
--- a/themes/binaryanomaly/binaryanomaly.theme.bash
+++ b/themes/binaryanomaly/binaryanomaly.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Detect whether a reboot is required
 function show_reboot_required() {
@@ -31,15 +33,6 @@ function set_user_color() {
 	esac
 }
 
-scm_prompt() {
-	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
diff --git a/themes/bira/bira.theme.bash b/themes/bira/bira.theme.bash
index ae8f0efe1e..7db03000cd 100644
--- a/themes/bira/bira.theme.bash
+++ b/themes/bira/bira.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=" ${yellow}‹"
 SCM_THEME_PROMPT_SUFFIX="›${reset_color}"
diff --git a/themes/bobby-python/bobby-python.theme.bash b/themes/bobby-python/bobby-python.theme.bash
index 9144e2519f..ebb3eab075 100644
--- a/themes/bobby-python/bobby-python.theme.bash
+++ b/themes/bobby-python/bobby-python.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
diff --git a/themes/bobby/bobby.theme.bash b/themes/bobby/bobby.theme.bash
index bdf388f72a..98d2cd8d8b 100644
--- a/themes/bobby/bobby.theme.bash
+++ b/themes/bobby/bobby.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${red}✗"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
diff --git a/themes/brainy/brainy.theme.bash b/themes/brainy/brainy.theme.bash
index db8377baf4..e1c3617531 100644
--- a/themes/brainy/brainy.theme.bash
+++ b/themes/brainy/brainy.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 # Brainy Bash Prompt for Bash-it
 # by MunifTanjim
diff --git a/themes/brunton/brunton.theme.bash b/themes/brunton/brunton.theme.bash
index c0bfd49ff2..166fcc84f8 100644
--- a/themes/brunton/brunton.theme.bash
+++ b/themes/brunton/brunton.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=""
 SCM_THEME_PROMPT_SUFFIX=""
@@ -15,16 +17,8 @@ is_vim_shell() {
 	fi
 }
 
-scm_prompt() {
-	CHAR=$(scm_char)
-	if [ "$CHAR" = "$SCM_NONE_CHAR" ]; then
-		return
-	else
-		echo " $(scm_char) (${white}$(scm_prompt_info)${normal})"
-	fi
-}
-
 prompt() {
+	SCM_PROMPT_FORMAT=' %s (%s)'
 	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} "
 }
 
diff --git a/themes/candy/candy.theme.bash b/themes/candy/candy.theme.bash
index be53d37356..7753e93426 100644
--- a/themes/candy/candy.theme.bash
+++ b/themes/candy/candy.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 function prompt_command() {
 	PS1="${green}\u@\h $(clock_prompt) ${reset_color}${white}\w${reset_color}$(scm_prompt_info)${blue} →${bold_blue} ${reset_color} ${normal}"
diff --git a/themes/codeword/codeword.theme.bash b/themes/codeword/codeword.theme.bash
index 96723ce345..beab6a4a79 100644
--- a/themes/codeword/codeword.theme.bash
+++ b/themes/codeword/codeword.theme.bash
@@ -1,18 +1,10 @@
+# shellcheck shell=bash
+
 SCM_THEME_PROMPT_PREFIX=${SCM_THEME_PROMPT_SUFFIX}
 SCM_THEME_PROMPT_DIRTY="${bold_red} ✗${normal}"
 SCM_THEME_PROMPT_CLEAN="${bold_green} ✓${normal}"
 SCM_GIT_CHAR="${green}±${normal}"
 
-scm_prompt() {
-    CHAR=$(scm_char)
-    if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-            return
-        else
-            echo " [$(scm_char)$(scm_prompt_info)]"
-    fi
-}
-
 mark_prompt() {
     echo "${green}\$${normal}"
 }
@@ -25,14 +17,9 @@ user_host_path_prompt() {
 }
 
 prompt() {
+  SCM_PROMPT_FORMAT=' [%s%s]'
   PS1="$(user_host_path_prompt)$(virtualenv_prompt)$(scm_prompt) $(mark_prompt) "
 }
 
-share_history() {
-  history -a
-  history -c
-  history -r
-}
-
-safe_append_prompt_command share_history
+safe_append_prompt_command '_save-and-reload-history 1'
 safe_append_prompt_command prompt
diff --git a/themes/colors.theme.bash b/themes/colors.theme.bash
index fbb1dc5c04..d5044d0505 100644
--- a/themes/colors.theme.bash
+++ b/themes/colors.theme.bash
@@ -1,4 +1,6 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
+# shellcheck disable=SC2005
+# shellcheck disable=SC2034
 
 function __ {
   echo "$@"
diff --git a/themes/demula/demula.theme.bash b/themes/demula/demula.theme.bash
index e85c18f7ca..7d8d6cc8fe 100644
--- a/themes/demula/demula.theme.bash
+++ b/themes/demula/demula.theme.bash
@@ -98,7 +98,7 @@ prompt() {
   local MOVE_CURSOR_RIGHTMOST='\033[500C'
   local MOVE_CURSOR_5_LEFT='\033[5D'
 
-  if [ $(uname) = "Linux" ];
+  if [[ "$OSTYPE" = 'linux'* ]]
   then
     PS1="${TITLEBAR}${SAVE_CURSOR}${MOVE_CURSOR_RIGHTMOST}${MOVE_CURSOR_5_LEFT}
 $(safe_battery_charge)${RESTORE_CURSOR}\
diff --git a/themes/doubletime/doubletime.theme.bash b/themes/doubletime/doubletime.theme.bash
index 3f686668b0..8186db736b 100644
--- a/themes/doubletime/doubletime.theme.bash
+++ b/themes/doubletime/doubletime.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 SCM_THEME_PROMPT_DIRTY=''
 SCM_THEME_PROMPT_CLEAN=''
@@ -28,45 +28,14 @@ else
     THEME_PROMPT_HOST_COLOR="$blue"
 fi
 
-doubletime_scm_prompt() {
-  CHAR=$(scm_char)
-  if [ $CHAR = $SCM_NONE_CHAR ]; then
-    return
-  elif [ $CHAR = $SCM_GIT_CHAR ]; then
-    echo "$(git_prompt_status)"
-  else
-    echo "[$(scm_prompt_info)]"
-  fi
-}
-
 function prompt_setter() {
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="
 $(clock_prompt) $(scm_char) [${THEME_PROMPT_HOST_COLOR}\u@${THEME_PROMPT_HOST}$reset_color] $(virtualenv_prompt)$(ruby_version_prompt)\w
-$(doubletime_scm_prompt)$reset_color $ "
+$(scm_prompt)$reset_color $ "
   PS2='> '
   PS4='+ '
 }
 
 safe_append_prompt_command prompt_setter
-
-git_prompt_status() {
-  local git_status_output
-  git_status_output=$(git status 2> /dev/null )
-  if [ -n "$(echo $git_status_output | grep 'Changes not staged')" ]; then
-    git_status="${bold_red}$(scm_prompt_info) ✗"
-  elif [ -n "$(echo $git_status_output | grep 'Changes to be committed')" ]; then
-     git_status="${bold_yellow}$(scm_prompt_info) ^"
-  elif [ -n "$(echo $git_status_output | grep 'Untracked files')" ]; then
-     git_status="${bold_cyan}$(scm_prompt_info) +"
-  elif [ -n "$(echo $git_status_output | grep 'nothing to commit')" ]; then
-     git_status="${bold_green}$(scm_prompt_info) ${green}✓"
-  else
-    git_status="$(scm_prompt_info)"
-  fi
-  echo "[$git_status${normal}]"
-
-}
diff --git a/themes/doubletime_multiline/doubletime_multiline.theme.bash b/themes/doubletime_multiline/doubletime_multiline.theme.bash
index 6da882533b..182135717d 100644
--- a/themes/doubletime_multiline/doubletime_multiline.theme.bash
+++ b/themes/doubletime_multiline/doubletime_multiline.theme.bash
@@ -1,12 +1,10 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 source "$BASH_IT/themes/doubletime/doubletime.theme.bash"
 
 function prompt_setter() {
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="
 $(clock_prompt) $(scm_char) [$THEME_PROMPT_HOST_COLOR\u@${THEME_PROMPT_HOST}$reset_color] $(virtualenv_prompt)$(ruby_version_prompt)
 \w
diff --git a/themes/doubletime_multiline_pyonly/doubletime_multiline_pyonly.theme.bash b/themes/doubletime_multiline_pyonly/doubletime_multiline_pyonly.theme.bash
index 5f1951e935..9bc4c33486 100644
--- a/themes/doubletime_multiline_pyonly/doubletime_multiline_pyonly.theme.bash
+++ b/themes/doubletime_multiline_pyonly/doubletime_multiline_pyonly.theme.bash
@@ -1,12 +1,10 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 source "$BASH_IT/themes/doubletime/doubletime.theme.bash"
 
 function prompt_setter() {
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="
 $(clock_prompt) $(scm_char) [$THEME_PROMPT_HOST_COLOR\u@${THEME_PROMPT_HOST}$reset_color] $(virtualenv_prompt)
 \w
diff --git a/themes/dulcie/dulcie.theme.bash b/themes/dulcie/dulcie.theme.bash
old mode 100644
new mode 100755
index a83b62fbc5..f70c786491
--- a/themes/dulcie/dulcie.theme.bash
+++ b/themes/dulcie/dulcie.theme.bash
@@ -77,7 +77,7 @@ dulcie_prompt() {
   printf "\033]0;%s@%s:%s\007" "${USER}" "${HOSTNAME%%.*}" "${PWD/#$HOME/\~}"
 
   # Open the new terminal in the same directory
-  declare -f __vte_osc7 > /dev/null && __vte_osc7
+  _is_function __vte_osc7 && __vte_osc7
 
   PS1="${reset_color}[${DULCIE_USER}@${DULCIE_HOST}$(scm_prompt_info)${reset_color} ${DULCIE_WORKINGDIR}]"
   if [[ "${DULCIE_MULTILINE}" -eq "1" ]]; then
diff --git a/themes/easy/easy.theme.bash b/themes/easy/easy.theme.bash
index a48eb8243a..7e2e3389ef 100644
--- a/themes/easy/easy.theme.bash
+++ b/themes/easy/easy.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX="${bold_green}[ ${normal}"
 SCM_THEME_PROMPT_SUFFIX="${bold_green} ] "
diff --git a/themes/gallifrey/gallifrey.theme.bash b/themes/gallifrey/gallifrey.theme.bash
index ddb89778c2..3ba48d71f5 100644
--- a/themes/gallifrey/gallifrey.theme.bash
+++ b/themes/gallifrey/gallifrey.theme.bash
@@ -4,26 +4,18 @@ SCM_THEME_PROMPT_SUFFIX=")${normal}"
 
 SCM_THEME_PROMPT_DIRTY="*"
 SCM_THEME_PROMPT_CLEAN=""
-SCM_GIT_CHAR="g"
-SCM_SVN_CHAR="s"
-SCM_HG_CHAR="h"
+SCM_GIT_CHAR="${green}±${normal}"
+SCM_SVN_CHAR="${bold_cyan}⑆${normal}"
+SCM_HG_CHAR="${bold_red}☿${normal}"
 
 ### TODO: openSUSE has already colors enabled, check if those differs from stock
 # LS colors, made with http://geoff.greer.fm/lscolors/
 # export LSCOLORS="Gxfxcxdxbxegedabagacad"
 # export LS_COLORS='no=00:fi=00:di=01;34:ln=00;36:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=41;33;01:ex=00;32:*.cmd=00;32:*.exe=01;32:*.com=01;32:*.bat=01;32:*.btm=01;32:*.dll=01;32:*.tar=00;31:*.tbz=00;31:*.tgz=00;31:*.rpm=00;31:*.deb=00;31:*.arj=00;31:*.taz=00;31:*.lzh=00;31:*.lzma=00;31:*.zip=00;31:*.zoo=00;31:*.z=00;31:*.Z=00;31:*.gz=00;31:*.bz2=00;31:*.tb2=00;31:*.tz2=00;31:*.tbz2=00;31:*.avi=01;35:*.bmp=01;35:*.fli=01;35:*.gif=01;35:*.jpg=01;35:*.jpeg=01;35:*.mng=01;35:*.mov=01;35:*.mpg=01;35:*.pcx=01;35:*.pbm=01;35:*.pgm=01;35:*.png=01;35:*.ppm=01;35:*.tga=01;35:*.tif=01;35:*.xbm=01;35:*.xpm=01;35:*.dl=01;35:*.gl=01;35:*.wmv=01;35:*.aiff=00;32:*.au=00;32:*.mid=00;32:*.mp3=00;32:*.ogg=00;32:*.voc=00;32:*.wav=00;32:'
 
-scm_prompt() {
-    CHAR=$(scm_char)
-    if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-            return
-        else
-            echo "$(scm_prompt_info) "
-    fi
-}
+gallifrey_prompt() {
+	SCM_PROMPT_FORMAT='%s%s'
 
-pure_prompt() {
     ps_host="${green}\h${normal}";
     ps_user_mark="${bold}\$${normal}";
     ps_root_mark="${normal}§"
@@ -38,4 +30,4 @@ pure_prompt() {
     esac
 }
 
-safe_append_prompt_command pure_prompt
+safe_append_prompt_command gallifrey_prompt
diff --git a/themes/liquidprompt/liquidprompt.theme.bash b/themes/liquidprompt/liquidprompt.theme.bash
old mode 100755
new mode 100644
diff --git a/themes/mairan/mairan.theme.bash b/themes/mairan/mairan.theme.bash
index e6728824b5..89466ead07 100644
--- a/themes/mairan/mairan.theme.bash
+++ b/themes/mairan/mairan.theme.bash
@@ -69,16 +69,6 @@ is_vim_shell() {
         fi
 }
 
-modern_scm_prompt() {
-        CHAR=$(scm_char)
-        if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-                return
-        else
-                echo "[$(scm_char)][$GREEN$(scm_prompt_info)]"
-        fi
-}
-
 # show chroot if exist
 chroot(){
     if [ -n "$debian_chroot" ]
@@ -99,7 +89,7 @@ my_ve(){
     }
 
 prompt() {
-
+	SCM_PROMPT_FORMAT="[%s$GREEN%s]"
     my_ps_host="$BOLD$ORANGE\h${normal}";
     # yes, these are the the same for now ...
     my_ps_host_root="$ORANGE\h${normal}";
@@ -114,10 +104,10 @@ prompt() {
 
     # nice prompt
     case "`id -u`" in
-        0) PS1="\n${TITLEBAR}${BRACKET_COLOR}┌─${normal}$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(modern_scm_prompt)$(__my_rvm_ruby_version)[${green}\w${normal}]$(is_vim_shell)${BRACKET_COLOR}
+        0) PS1="\n${TITLEBAR}${BRACKET_COLOR}┌─${normal}$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(scm_prompt)$(__my_rvm_ruby_version)[${green}\w${normal}]$(is_vim_shell)${BRACKET_COLOR}
 └─▪ ${prompt_symbol} ${normal}"
         ;;
-        *) PS1="\n${TITLEBAR}${BRACKET_COLOR}┌─${normal}$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(modern_scm_prompt)${normal}$(__my_rvm_ruby_version)[${green}\w${normal}]$(is_vim_shell)${BRACKET_COLOR}
+        *) PS1="\n${TITLEBAR}${BRACKET_COLOR}┌─${normal}$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(scm_prompt)${normal}$(__my_rvm_ruby_version)[${green}\w${normal}]$(is_vim_shell)${BRACKET_COLOR}
 └─▪ ${prompt_symbol} ${normal}"
         ;;
     esac
diff --git a/themes/modern-t/modern-t.theme.bash b/themes/modern-t/modern-t.theme.bash
index 48e923aa48..197f5a2345 100644
--- a/themes/modern-t/modern-t.theme.bash
+++ b/themes/modern-t/modern-t.theme.bash
@@ -32,26 +32,17 @@ is_vim_shell() {
 	fi
 }
 
-modern_scm_prompt() {
-	CHAR=$(scm_char)
-	if [ $CHAR = $SCM_NONE_CHAR ]
-	then
-		return
-	else
-		echo "[$(scm_char)][$(scm_prompt_info)]"
-	fi
-}
-
 prompt() {
+	SCM_PROMPT_FORMAT='[%s][%s]'
 	if [ $? -ne 0 ]
 	then
 		# Yes, the indenting on these is weird, but it has to be like
 		# this otherwise it won't display properly.
 
-		PS1="${TITLEBAR}${bold_red}┌─[${cyan}$(t | wc -l | sed -e's/ *//')${reset_color}]${reset_color}$(modern_scm_prompt)[${cyan}\W${normal}]$(is_vim_shell)
+		PS1="${TITLEBAR}${bold_red}┌─[${cyan}$(t | wc -l | sed -e's/ *//')${reset_color}]${reset_color}$(scm_prompt)[${cyan}\W${normal}]$(is_vim_shell)
 ${bold_red}└─▪${normal} "
 	else
-		PS1="${TITLEBAR}┌─[${cyan}$(t | wc -l | sed -e's/ *//')${reset_color}]$(modern_scm_prompt)[${cyan}\W${normal}]$(is_vim_shell)
+		PS1="${TITLEBAR}┌─[${cyan}$(t | wc -l | sed -e's/ *//')${reset_color}]$(scm_prompt)[${cyan}\W${normal}]$(is_vim_shell)
 └─▪ "
 	fi
 }
diff --git a/themes/modern-time/modern-time.theme.bash b/themes/modern-time/modern-time.theme.bash
index e42226df14..fc8458fffe 100644
--- a/themes/modern-time/modern-time.theme.bash
+++ b/themes/modern-time/modern-time.theme.bash
@@ -28,30 +28,21 @@ is_vim_shell() {
 	fi
 }
 
-modern_scm_prompt() {
-	CHAR=$(scm_char)
-	if [ $CHAR = $SCM_NONE_CHAR ]
-	then
-		return
-	else
-		echo "[$(scm_char)][$(scm_prompt_info)]"
-	fi
-}
-
 modern_current_time_prompt() {
 	echo "[$(date '+%l:%M%p')]"
 }
 
 prompt() {
+	SCM_PROMPT_FORMAT='[%s][%s]'
 	if [ $? -ne 0 ]
 	then
 		# Yes, the indenting on these is weird, but it has to be like
 		# this otherwise it won't display properly.
 
-		PS1="${TITLEBAR}${bold_red}┌─${reset_color}$(modern_scm_prompt)$(modern_current_time_prompt)[${cyan}\W${normal}]$(is_vim_shell)
+		PS1="${TITLEBAR}${bold_red}┌─${reset_color}$(scm_prompt)$(modern_current_time_prompt)[${cyan}\W${normal}]$(is_vim_shell)
 ${bold_red}└─▪${normal} "
 	else
-		PS1="${TITLEBAR}┌─$(modern_scm_prompt)$(modern_current_time_prompt)[${cyan}\W${normal}]$(is_vim_shell)
+		PS1="${TITLEBAR}┌─$(scm_prompt)$(modern_current_time_prompt)[${cyan}\W${normal}]$(is_vim_shell)
 └─▪ "
 	fi
 }
diff --git a/themes/modern/modern.theme.bash b/themes/modern/modern.theme.bash
index f14fd4fddc..eadb07624f 100644
--- a/themes/modern/modern.theme.bash
+++ b/themes/modern/modern.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_PREFIX=""
 SCM_THEME_PROMPT_SUFFIX=""
@@ -26,15 +28,6 @@ is_vim_shell() {
 	fi
 }
 
-modern_scm_prompt() {
-	CHAR=$(scm_char)
-	if [ "$CHAR" = "$SCM_NONE_CHAR" ]; then
-		return
-	else
-		echo "[$(scm_char)][$(scm_prompt_info)]"
-	fi
-}
-
 detect_venv() {
 	python_venv=""
 	# Detect python venv
@@ -46,11 +39,12 @@ detect_venv() {
 }
 
 prompt() {
+	SCM_PROMPT_FORMAT='[%s][%s]'
 	retval=$?
 	if [[ retval -ne 0 ]]; then
-		PS1="${TITLEBAR}${bold_red}┌─${reset_color}$(modern_scm_prompt)[${cyan}\u${normal}][${cyan}\w${normal}]$(is_vim_shell)\n${bold_red}└─▪${normal} "
+		PS1="${TITLEBAR}${bold_red}┌─${reset_color}$(scm_prompt)[${cyan}\u${normal}][${cyan}\w${normal}]$(is_vim_shell)\n${bold_red}└─▪${normal} "
 	else
-		PS1="${TITLEBAR}┌─$(modern_scm_prompt)[${cyan}\u${normal}][${cyan}\w${normal}]$(is_vim_shell)\n└─▪ "
+		PS1="${TITLEBAR}┌─$(scm_prompt)[${cyan}\u${normal}][${cyan}\w${normal}]$(is_vim_shell)\n└─▪ "
 	fi
 	detect_venv
 	PS1+="${python_venv}${dir_color}"
diff --git a/themes/nwinkler/nwinkler.theme.bash b/themes/nwinkler/nwinkler.theme.bash
index f9fe4933cc..983c8d0020 100644
--- a/themes/nwinkler/nwinkler.theme.bash
+++ b/themes/nwinkler/nwinkler.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 # Two line prompt showing the following information:
 # (time) SCM [username@hostname] pwd (SCM branch SCM status)
@@ -29,9 +29,7 @@ prompt_setter() {
     else PROMPT_END=$PROMPT_END_DIRTY
   fi
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="($(clock_prompt)) $(scm_char) [${blue}\u${reset_color}@${green}\H${reset_color}] ${yellow}\w${reset_color}$(scm_prompt_info) ${reset_color}\n$(prompt_end) "
   PS2='> '
   PS4='+ '
diff --git a/themes/nwinkler_random_colors/nwinkler_random_colors.theme.bash b/themes/nwinkler_random_colors/nwinkler_random_colors.theme.bash
index f6eff908d7..05391b0b7b 100644
--- a/themes/nwinkler_random_colors/nwinkler_random_colors.theme.bash
+++ b/themes/nwinkler_random_colors/nwinkler_random_colors.theme.bash
@@ -1,4 +1,4 @@
-#!/bin/bash
+# shellcheck shell=bash
 
 # Two line prompt showing the following information:
 # (time) SCM [username@hostname] pwd (SCM branch SCM status)
@@ -96,9 +96,7 @@ prompt_setter() {
     else PROMPT_END=$PROMPT_END_DIRTY
   fi
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="($(clock_prompt)${reset_color}) $(scm_char) [${USERNAME_COLOR}\u${reset_color}@${HOSTNAME_COLOR}\H${reset_color}] ${PATH_COLOR}\w${reset_color}$(scm_prompt_info) ${reset_color}\n$(prompt_end) "
   PS2='> '
   PS4='+ '
diff --git a/themes/pete/pete.theme.bash b/themes/pete/pete.theme.bash
index 73fdb05318..d29553f82d 100644
--- a/themes/pete/pete.theme.bash
+++ b/themes/pete/pete.theme.bash
@@ -1,10 +1,8 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 prompt_setter() {
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   PS1="($(clock_prompt)) $(scm_char) [$blue\u$reset_color@$green\H$reset_color] $yellow\w${reset_color}$(scm_prompt_info)$(ruby_version_prompt) $reset_color "
   PS2='> '
   PS4='+ '
diff --git a/themes/powerline-multiline/powerline-multiline.theme.bash b/themes/powerline-multiline/powerline-multiline.theme.bash
index e15c362178..b1c4efbadb 100644
--- a/themes/powerline-multiline/powerline-multiline.theme.bash
+++ b/themes/powerline-multiline/powerline-multiline.theme.bash
@@ -55,6 +55,9 @@ TERRAFORM_CHAR=${POWERLINE_TERRAFORM_CHAR:="❲t❳ "}
 KUBERNETES_CONTEXT_THEME_CHAR=${POWERLINE_KUBERNETES_CONTEXT_CHAR:="⎈ "}
 KUBERNETES_CONTEXT_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_CONTEXT_COLOR:=26}
 
+KUBERNETES_NAMESPACE_THEME_CHAR=${POWERLINE_KUBERNETES_NAMESPACE_CHAR:="⎈ "}
+KUBERNETES_NAMESPACE_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_NAMESPACE_COLOR:=64}
+
 AWS_PROFILE_CHAR=${POWERLINE_AWS_PROFILE_CHAR:="❲aws❳ "}
 AWS_PROFILE_PROMPT_COLOR=${POWERLINE_AWS_PROFILE_COLOR:=208}
 
@@ -94,6 +97,8 @@ COMMAND_NUMBER_THEME_PROMPT_CHAR=${POWERLINE_COMMAND_NUMBER_CHAR:="#"}
 GCLOUD_THEME_PROMPT_COLOR=${POWERLINE_GCLOUD_COLOR:=161}
 GCLOUD_CHAR=${POWERLINE_GCLOUD_CHAR:="❲G❳ "}
 
+COMMAND_DURATION_PROMPT_COLOR=${POWERLINE_COMMAND_DURATION_COLOR:=129}
+
 POWERLINE_LEFT_PROMPT=${POWERLINE_LEFT_PROMPT:="scm python_venv ruby node cwd"}
 POWERLINE_RIGHT_PROMPT=${POWERLINE_RIGHT_PROMPT:="in_vim clock battery user_info"}
 
diff --git a/themes/powerline-naked/powerline-naked.theme.bash b/themes/powerline-naked/powerline-naked.theme.bash
index 72c986baab..a857675717 100644
--- a/themes/powerline-naked/powerline-naked.theme.bash
+++ b/themes/powerline-naked/powerline-naked.theme.bash
@@ -50,6 +50,9 @@ TERRAFORM_CHAR=${POWERLINE_TERRAFORM_CHAR:="❲t❳ "}
 KUBERNETES_CONTEXT_THEME_CHAR=${POWERLINE_KUBERNETES_CONTEXT_CHAR:="⎈ "}
 KUBERNETES_CONTEXT_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_CONTEXT_COLOR:=26}
 
+KUBERNETES_NAMESPACE_THEME_CHAR=${POWERLINE_KUBERNETES_NAMESPACE_CHAR:="⎈ "}
+KUBERNETES_NAMESPACE_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_NAMESPACE_COLOR:=64}
+
 AWS_PROFILE_CHAR=${POWERLINE_AWS_PROFILE_CHAR:="❲aws❳ "}
 AWS_PROFILE_PROMPT_COLOR=${POWERLINE_AWS_PROFILE_COLOR:=208}
 
diff --git a/themes/powerline-plain/powerline-plain.theme.bash b/themes/powerline-plain/powerline-plain.theme.bash
index 9ea6cde929..bdba9bd0a7 100644
--- a/themes/powerline-plain/powerline-plain.theme.bash
+++ b/themes/powerline-plain/powerline-plain.theme.bash
@@ -47,6 +47,9 @@ TERRAFORM_CHAR=${POWERLINE_TERRAFORM_CHAR:="❲t❳ "}
 KUBERNETES_CONTEXT_THEME_CHAR=${POWERLINE_KUBERNETES_CONTEXT_CHAR:="⎈ "}
 KUBERNETES_CONTEXT_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_CONTEXT_COLOR:=26}
 
+KUBERNETES_NAMESPACE_THEME_CHAR=${POWERLINE_KUBERNETES_NAMESPACE_CHAR:="⎈ "}
+KUBERNETES_NAMESPACE_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_NAMESPACE_COLOR:=60}
+
 AWS_PROFILE_CHAR=${POWERLINE_AWS_PROFILE_CHAR:="❲aws❳ "}
 AWS_PROFILE_PROMPT_COLOR=${POWERLINE_AWS_PROFILE_COLOR:=208}
 
diff --git a/themes/powerline/powerline.base.bash b/themes/powerline/powerline.base.bash
index ed0499c7f6..ce4fc29023 100644
--- a/themes/powerline/powerline.base.bash
+++ b/themes/powerline/powerline.base.bash
@@ -1,4 +1,7 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
+
 # Define this here so it can be used by all of the Powerline themes
 THEME_CHECK_SUDO=${THEME_CHECK_SUDO:=true}
 
@@ -85,6 +88,16 @@ function __powerline_k8s_context_prompt() {
 	[[ -n "${kubernetes_context}" ]] && echo "${KUBERNETES_CONTEXT_THEME_CHAR}${kubernetes_context}|${KUBERNETES_CONTEXT_THEME_PROMPT_COLOR}"
 }
 
+function __powerline_k8s_namespace_prompt() {
+	local kubernetes_namespace=""
+
+	if _command_exists kubectl; then
+		kubernetes_namespace="$(k8s_namespace_prompt)"
+	fi
+
+	[[ -n "${kubernetes_namespace}" ]] && echo "${KUBERNETES_NAMESPACE_THEME_CHAR}${kubernetes_namespace}|${KUBERNETES_NAMESPACE_THEME_PROMPT_COLOR}"
+}
+
 function __powerline_python_venv_prompt() {
 	set +u
 	local python_venv=""
@@ -129,7 +142,7 @@ function __powerline_scm_prompt() {
 }
 
 function __powerline_cwd_prompt() {
-	local cwd=$(pwd | sed "s|^${HOME}|~|")
+	local cwd="${PWD/$HOME/\~}"
 
 	echo "${cwd}|${CWD_THEME_PROMPT_COLOR}"
 }
@@ -147,10 +160,10 @@ function __powerline_clock_prompt() {
 }
 
 function __powerline_battery_prompt() {
-	local color=""
-	local battery_status="$(battery_percentage 2> /dev/null)"
+	local color="" battery_status
+	battery_status="$(battery_percentage 2> /dev/null)"
 
-	if [[ -z "${battery_status}" ]] || [[ "${battery_status}" = "-1" ]] || [[ "${battery_status}" = "no" ]]; then
+	if [[ -z "${battery_status}" || "${battery_status}" == "-1" || "${battery_status}" == "no" ]]; then
 		true
 	else
 		if [[ "$((10#${battery_status}))" -le 5 ]]; then
@@ -166,7 +179,7 @@ function __powerline_battery_prompt() {
 }
 
 function __powerline_in_vim_prompt() {
-	if [ -n "$VIMRUNTIME" ]; then
+	if [[ -n "$VIMRUNTIME" ]]; then
 		echo "${IN_VIM_THEME_PROMPT_TEXT}|${IN_VIM_THEME_PROMPT_COLOR}"
 	fi
 }
@@ -210,6 +223,12 @@ function __powerline_command_number_prompt() {
 	echo "${COMMAND_NUMBER_THEME_PROMPT_CHAR}\#|${COMMAND_NUMBER_THEME_PROMPT_COLOR}"
 }
 
+function __powerline_duration_prompt() {
+	local duration
+	duration=$(_command_duration)
+	[[ -n "$duration" ]] && echo "${duration}|${COMMAND_DURATION_PROMPT_COLOR}"
+}
+
 function __powerline_left_segment() {
 	local params
 	IFS="|" read -ra params <<< "${1}"
@@ -250,7 +269,7 @@ function __powerline_last_status_prompt() {
 
 function __powerline_prompt_command() {
 	local last_status="$?" ## always the first
-	local separator_char="${POWERLINE_PROMPT_CHAR}"
+	local separator_char="${POWERLINE_PROMPT_CHAR}" info prompt_color
 
 	LEFT_PROMPT=""
 	SEGMENTS_AT_LEFT=0
@@ -263,7 +282,7 @@ function __powerline_prompt_command() {
 
 	## left prompt ##
 	for segment in $POWERLINE_PROMPT; do
-		local info="$(__powerline_"${segment}"_prompt)"
+		info="$(__powerline_"${segment}"_prompt)"
 		[[ -n "${info}" ]] && __powerline_left_segment "${info}"
 	done
 
@@ -275,7 +294,7 @@ function __powerline_prompt_command() {
 
 	# By default we try to match the prompt to the adjacent segment's background color,
 	# but when part of the prompt exists within that segment, we instead match the foreground color.
-	local prompt_color="$(set_color "${LAST_SEGMENT_COLOR}" -)"
+	prompt_color="$(set_color "${LAST_SEGMENT_COLOR}" -)"
 	if [[ -n "${LEFT_PROMPT}" ]] && [[ -n "${POWERLINE_LEFT_LAST_SEGMENT_PROMPT_CHAR}" ]]; then
 		LEFT_PROMPT+="$(set_color - "${LAST_SEGMENT_COLOR}")${POWERLINE_LEFT_LAST_SEGMENT_PROMPT_CHAR}"
 		prompt_color="${normal}"
diff --git a/themes/powerline/powerline.theme.bash b/themes/powerline/powerline.theme.bash
index 794121b887..49b397aa1d 100644
--- a/themes/powerline/powerline.theme.bash
+++ b/themes/powerline/powerline.theme.bash
@@ -1,4 +1,5 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 
 # shellcheck source=../../themes/powerline/powerline.base.bash
 . "$BASH_IT/themes/powerline/powerline.base.bash"
@@ -52,6 +53,9 @@ TERRAFORM_CHAR=${POWERLINE_TERRAFORM_CHAR:="❲t❳ "}
 KUBERNETES_CONTEXT_THEME_CHAR=${POWERLINE_KUBERNETES_CONTEXT_CHAR:="⎈ "}
 KUBERNETES_CONTEXT_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_CONTEXT_COLOR:=26}
 
+KUBERNETES_NAMESPACE_THEME_CHAR=${POWERLINE_KUBERNETES_NAMESPACE_CHAR:="⎈ "}
+KUBERNETES_NAMESPACE_THEME_PROMPT_COLOR=${POWERLINE_KUBERNETES_NAMESPACE_COLOR:=64}
+
 AWS_PROFILE_CHAR=${POWERLINE_AWS_PROFILE_CHAR:="❲aws❳ "}
 AWS_PROFILE_PROMPT_COLOR=${POWERLINE_AWS_PROFILE_COLOR:=208}
 
@@ -91,6 +95,8 @@ COMMAND_NUMBER_THEME_PROMPT_CHAR=${POWERLINE_COMMAND_NUMBER_CHAR:="#"}
 GCLOUD_THEME_PROMPT_COLOR=${POWERLINE_GCLOUD_COLOR:=161}
 GCLOUD_CHAR=${POWERLINE_GCLOUD_CHAR:="❲G❳ "}
 
+COMMAND_DURATION_PROMPT_COLOR=${POWERLINE_COMMAND_DURATION_COLOR:=129}
+
 POWERLINE_PROMPT=${POWERLINE_PROMPT:="user_info scm python_venv ruby node cwd"}
 
 safe_append_prompt_command __powerline_prompt_command
diff --git a/themes/powerturk/powerturk.theme.bash b/themes/powerturk/powerturk.theme.bash
index 4590a8aad3..3352f68006 100644
--- a/themes/powerturk/powerturk.theme.bash
+++ b/themes/powerturk/powerturk.theme.bash
@@ -43,7 +43,7 @@ _swd(){
     begin="" # The unshortened beginning of the path.
     shortbegin="" # The shortened beginning of the path.
     current="" # The section of the path we're currently working on.
-    end="${2:-$(pwd)}/" # The unmodified rest of the path.
+    end="${2:-${PWD}}/" # The unmodified rest of the path.
 
     if [[ "$end" =~ "$HOME" ]]; then
         INHOME=1
diff --git a/themes/pure/pure.theme.bash b/themes/pure/pure.theme.bash
index 0be40b5ae2..99476f4ade 100644
--- a/themes/pure/pure.theme.bash
+++ b/themes/pure/pure.theme.bash
@@ -1,3 +1,7 @@
+# shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
+
 # scm theming
 SCM_THEME_PROMPT_PREFIX="|"
 SCM_THEME_PROMPT_SUFFIX=""
@@ -16,31 +20,22 @@ VIRTUALENV_THEME_PROMPT_SUFFIX=")"
 # export LSCOLORS="Gxfxcxdxbxegedabagacad"
 # export LS_COLORS='no=00:fi=00:di=01;34:ln=00;36:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=41;33;01:ex=00;32:*.cmd=00;32:*.exe=01;32:*.com=01;32:*.bat=01;32:*.btm=01;32:*.dll=01;32:*.tar=00;31:*.tbz=00;31:*.tgz=00;31:*.rpm=00;31:*.deb=00;31:*.arj=00;31:*.taz=00;31:*.lzh=00;31:*.lzma=00;31:*.zip=00;31:*.zoo=00;31:*.z=00;31:*.Z=00;31:*.gz=00;31:*.bz2=00;31:*.tb2=00;31:*.tz2=00;31:*.tbz2=00;31:*.avi=01;35:*.bmp=01;35:*.fli=01;35:*.gif=01;35:*.jpg=01;35:*.jpeg=01;35:*.mng=01;35:*.mov=01;35:*.mpg=01;35:*.pcx=01;35:*.pbm=01;35:*.pgm=01;35:*.png=01;35:*.ppm=01;35:*.tga=01;35:*.tif=01;35:*.xbm=01;35:*.xpm=01;35:*.dl=01;35:*.gl=01;35:*.wmv=01;35:*.aiff=00;32:*.au=00;32:*.mid=00;32:*.mp3=00;32:*.ogg=00;32:*.voc=00;32:*.wav=00;32:'
 
-scm_prompt() {
-    CHAR=$(scm_char)
-    if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-            return
-        else
-            echo "[$(scm_char)$(scm_prompt_info)]"
-    fi
-}
-
 pure_prompt() {
-    ps_host="${bold_blue}\h${normal}";
-    ps_user="${green}\u${normal}";
-    ps_user_mark="${green} $ ${normal}";
-    ps_root="${red}\u${red}";
-    ps_root_mark="${red} # ${normal}"
-    ps_path="${yellow}\w${normal}";
-
-    # make it work
-    case $(id -u) in
-        0) PS1="$(virtualenv_prompt)$ps_root@$ps_host$(scm_prompt):$ps_path$ps_root_mark"
-            ;;
-        *) PS1="$(virtualenv_prompt)$ps_user@$ps_host$(scm_prompt):$ps_path$ps_user_mark"
-            ;;
-    esac
+	ps_host="${bold_blue}\h${normal}"
+	ps_user="${green}\u${normal}"
+	ps_user_mark="${green} $ ${normal}"
+	ps_root="${red}\u${red}"
+	ps_root_mark="${red} # ${normal}"
+	ps_path="${yellow}\w${normal}"
+	# make it work
+	case $(id -u) in
+		0)
+			PS1="$(virtualenv_prompt)$ps_root@$ps_host$(scm_prompt):$ps_path$ps_root_mark"
+			;;
+		*)
+			PS1="$(virtualenv_prompt)$ps_user@$ps_host$(scm_prompt):$ps_path$ps_user_mark"
+			;;
+	esac
 }
 
 safe_append_prompt_command pure_prompt
diff --git a/themes/purity/purity.theme.bash b/themes/purity/purity.theme.bash
index 8fc03bf32d..22a3fbfbb6 100644
--- a/themes/purity/purity.theme.bash
+++ b/themes/purity/purity.theme.bash
@@ -1,4 +1,6 @@
 # shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
+# shellcheck disable=SC2154 #TODO: fix these all.
 
 SCM_THEME_PROMPT_DIRTY=" ${bold_red}⊘${normal}"
 SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓${normal}"
@@ -26,8 +28,8 @@ venv_prompt() {
 }
 
 function prompt_command() {
-	retval=$?
-	local ret_status="$([ $retval -eq 0 ] && echo -e "$STATUS_THEME_PROMPT_OK" || echo -e "$STATUS_THEME_PROMPT_BAD")"
+	local retval=$? ret_status
+	ret_status="$([ $retval -eq 0 ] && echo -e "$STATUS_THEME_PROMPT_OK" || echo -e "$STATUS_THEME_PROMPT_BAD")"
 	PS1="\n${PURITY_THEME_PROMPT_COLOR}\w $(scm_prompt_info)\n${ret_status}$(venv_prompt)"
 }
 
diff --git a/themes/rainbowbrite/rainbowbrite.theme.bash b/themes/rainbowbrite/rainbowbrite.theme.bash
index 63c64b72d2..07e5843fcf 100644
--- a/themes/rainbowbrite/rainbowbrite.theme.bash
+++ b/themes/rainbowbrite/rainbowbrite.theme.bash
@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
 
 # based off of n0qorg
 # looks like, if you're in a git repo:
@@ -7,9 +7,7 @@
 
 prompt_setter() {
   # Save history
-  history -a
-  history -c
-  history -r
+  _save-and-reload-history 1
   # displays user@server in purple
   # PS1="$red$(scm_char) $purple\u@\h$reset_color:$blue\w$yellow$(scm_prompt_info)$(ruby_version_prompt) $black\$$reset_color "
   # no user@server
diff --git a/themes/ramses/ramses.theme.bash b/themes/ramses/ramses.theme.bash
index 7795cf7578..054a316024 100644
--- a/themes/ramses/ramses.theme.bash
+++ b/themes/ramses/ramses.theme.bash
@@ -36,16 +36,6 @@ is_vim_shell() {
         fi
 }
 
-modern_scm_prompt() {
-        CHAR=$(scm_char)
-        if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-                return
-        else
-                echo "[$(scm_char)][$(scm_prompt_info)]"
-        fi
-}
-
 # show chroot if exist
 chroot(){
     if [ -n "$debian_chroot" ]
@@ -71,7 +61,7 @@ my_ve(){
     }
 
 prompt() {
-
+    SCM_PROMPT_FORMAT='[%s][%s]'
     my_ps_host="${green}\h${normal}";
     # yes, these are the the same for now ...
     my_ps_host_root="${green}\h${normal}";
@@ -86,10 +76,10 @@ prompt() {
 
     # nice prompt
     case "`id -u`" in
-        0) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(modern_scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]
+        0) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]
 ▪ "
         ;;
-        *) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(modern_scm_prompt)$(__my_rvm_ruby_version)
+        *) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(scm_prompt)$(__my_rvm_ruby_version)
 |─[${bold_purple}\w${normal}]
 ▪ "
         ;;
diff --git a/themes/rana/rana.theme.bash b/themes/rana/rana.theme.bash
index 255303973f..3da74d6db7 100644
--- a/themes/rana/rana.theme.bash
+++ b/themes/rana/rana.theme.bash
@@ -181,7 +181,7 @@ prompt() {
   local MOVE_CURSOR_RIGHTMOST='\033[500C'
   local MOVE_CURSOR_5_LEFT='\033[5D'
 
-  if [ $(uname) = "Linux" ];
+  if [[ "$OSTYPE" == 'linux'* ]];
   then
     PS1="${TITLEBAR}
 ${SAVE_CURSOR}${MOVE_CURSOR_RIGHTMOST}${MOVE_CURSOR_5_LEFT}\
diff --git a/themes/rjorgenson/rjorgenson.theme.bash b/themes/rjorgenson/rjorgenson.theme.bash
index e866f0ea4c..71d29e7866 100644
--- a/themes/rjorgenson/rjorgenson.theme.bash
+++ b/themes/rjorgenson/rjorgenson.theme.bash
@@ -57,16 +57,6 @@ todo_txt_count() {
     fi
 }
 
-modern_scm_prompt() {
-        CHAR=$(scm_char)
-        if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-                return
-        else
-                echo "${BRACKET_COLOR}[${CHAR}${BRACKET_COLOR}][${STRING_COLOR}$(scm_prompt_info)${BRACKET_COLOR}]$normal"
-        fi
-}
-
 my_prompt_char() {
     if [[ $OSTYPE =~ "darwin" ]]; then
         echo "${BRACKET_COLOR}➞  ${normal}"
@@ -76,6 +66,7 @@ my_prompt_char() {
 }
 
 prompt() {
+	SCM_PROMPT_FORMAT="${BRACKET_COLOR}[%s${BRACKET_COLOR}][${STRING_COLOR}%s${BRACKET_COLOR}]"
 
     my_ps_host="${STRING_COLOR}\h${normal}";
     my_ps_user="${STRING_COLOR}\u${normal}";
@@ -84,10 +75,10 @@ prompt() {
 
     # nice prompt
     case "`id -u`" in
-        0) PS1="${TITLEBAR}${BRACKET_COLOR}┌─[$my_ps_root${BRACKET_COLOR}][$my_ps_host${BRACKET_COLOR}]$(modern_scm_prompt)$(__my_rvm_ruby_version)${BRACKET_COLOR}[${STRING_COLOR}\w${BRACKET_COLOR}]$(is_vim_shell)
+        0) PS1="${TITLEBAR}${BRACKET_COLOR}┌─[$my_ps_root${BRACKET_COLOR}][$my_ps_host${BRACKET_COLOR}]$(scm_prompt)$(__my_rvm_ruby_version)${BRACKET_COLOR}[${STRING_COLOR}\w${BRACKET_COLOR}]$(is_vim_shell)
 ${BRACKET_COLOR}└─$(my_prompt_char)${normal}"
         ;;
-        *) PS1="${TITLEBAR}${BRACKET_COLOR}┌─[$my_ps_user${BRACKET_COLOR}][$my_ps_host${BRACKET_COLOR}]$(modern_scm_prompt)$(__my_rvm_ruby_version)${BRACKET_COLOR}[${STRING_COLOR}\w${BRACKET_COLOR}]$(is_vim_shell)
+        *) PS1="${TITLEBAR}${BRACKET_COLOR}┌─[$my_ps_user${BRACKET_COLOR}][$my_ps_host${BRACKET_COLOR}]$(scm_prompt)$(__my_rvm_ruby_version)${BRACKET_COLOR}[${STRING_COLOR}\w${BRACKET_COLOR}]$(is_vim_shell)
 ${BRACKET_COLOR}└─$(todo_txt_count)$(my_prompt_char)"
         ;;
     esac
diff --git a/themes/slick/slick.theme.bash b/themes/slick/slick.theme.bash
index aafdc25d15..b0979b7cb8 100644
--- a/themes/slick/slick.theme.bash
+++ b/themes/slick/slick.theme.bash
@@ -43,18 +43,8 @@ is_vim_shell() {
         fi
 }
 
-modern_scm_prompt() {
-        CHAR=$(scm_char)
-        if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-                return
-        else
-                echo "[$(scm_char)][$(scm_prompt_info)]"
-        fi
-}
-
 prompt() {
-
+   SCM_PROMPT_FORMAT='[%s][%s]'
    case $HOSTNAME in
     "clappy"* ) my_ps_host="${green}\h${normal}";
             ;;
@@ -70,10 +60,10 @@ prompt() {
 
     # nice prompt
     case "`id -u`" in
-        0) PS1="${TITLEBAR}[$my_ps_root][$my_ps_host]$(modern_scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
+        0) PS1="${TITLEBAR}[$my_ps_root][$my_ps_host]$(scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
 $ "
         ;;
-      *) PS1="${TITLEBAR}[$my_ps_user][$my_ps_host]$(modern_scm_prompt)$(__my_rvm_ruby_version)$(__my_venv_prompt)[${cyan}\w${normal}]$(is_vim_shell)
+      *) PS1="${TITLEBAR}[$my_ps_user][$my_ps_host]$(scm_prompt)$(__my_rvm_ruby_version)$(__my_venv_prompt)[${cyan}\w${normal}]$(is_vim_shell)
 $ "
         ;;
     esac
diff --git a/themes/zork/zork.theme.bash b/themes/zork/zork.theme.bash
index b587231438..c80534501a 100644
--- a/themes/zork/zork.theme.bash
+++ b/themes/zork/zork.theme.bash
@@ -36,16 +36,6 @@ is_vim_shell() {
         fi
 }
 
-modern_scm_prompt() {
-        CHAR=$(scm_char)
-        if [ $CHAR = $SCM_NONE_CHAR ]
-        then
-                return
-        else
-                echo "[$(scm_char)][$(scm_prompt_info)]"
-        fi
-}
-
 # show chroot if exist
 chroot(){
     if [ -n "$debian_chroot" ]
@@ -71,7 +61,7 @@ my_ve(){
     }
 
 prompt() {
-
+	SCM_PROMPT_FORMAT='[%s][%s]'
     my_ps_host="${green}\h${normal}";
     # yes, these are the the same for now ...
     my_ps_host_root="${green}\h${normal}";
@@ -86,10 +76,10 @@ prompt() {
 
     # nice prompt
     case "`id -u`" in
-        0) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(modern_scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
+        0) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_root][$my_ps_host_root]$(scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
 └─▪ "
         ;;
-        *) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(modern_scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
+        *) PS1="${TITLEBAR}┌─$(my_ve)$(chroot)[$my_ps_user][$my_ps_host]$(scm_prompt)$(__my_rvm_ruby_version)[${cyan}\w${normal}]$(is_vim_shell)
 └─▪ "
         ;;
     esac