diff --git a/.gitmodules b/.gitmodules
index fcc482621e..547effa3e7 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -28,6 +28,8 @@
 [submodule "modules/prompt/external/powerlevel9k"]
 	path = modules/prompt/external/powerlevel9k
 	url = https://github.com/bhilburn/powerlevel9k.git
+	shallow = true
 [submodule "modules/prompt/external/powerlevel10k"]
 	path = modules/prompt/external/powerlevel10k
 	url = https://github.com/romkatv/powerlevel10k.git
+	shallow = true
diff --git a/README.md b/README.md
index 552784bae7..45ef61ce40 100644
--- a/README.md
+++ b/README.md
@@ -59,7 +59,7 @@ Updating
 
 Run `zprezto-update` to automatically check if there is an update to zprezto.
 If there are no file conflicts, zprezto and its submodules will be
-automatically updated. If there are conflicts you will instructed to go into
+automatically updated. If there are conflicts you will be instructed to go into
 the `$ZPREZTODIR` directory and resolve them yourself.
 
 To pull the latest changes and update submodules manually:
diff --git a/modules/command-not-found/init.zsh b/modules/command-not-found/init.zsh
index f3d7ea6287..35884ce6e0 100644
--- a/modules/command-not-found/init.zsh
+++ b/modules/command-not-found/init.zsh
@@ -21,11 +21,12 @@ elif (( $+commands[brew] )); then
     "$(brew --repository 2> /dev/null)"/Library/Taps/*/*/cmd/brew-command-not-found-init(|.rb)(.N)
   )
   if (( $#cnf_command )); then
-    cache_file="${TMPDIR:-/tmp}/prezto-brew-command-not-found-cache.$UID.zsh"
+    cache_file="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/brew-command-not-found-cache.zsh"
 
     if [[ "${${(@o)cnf_command}[1]}" -nt "$cache_file" \
           || "${ZDOTDIR:-$HOME}/.zpreztorc" -nt "$cache_file" \
           || ! -s "$cache_file" ]]; then
+      mkdir -p "$cache_file:h"
       # brew command-not-found-init is slow; cache its output.
       brew command-not-found-init >! "$cache_file" 2> /dev/null
     fi
diff --git a/modules/completion/init.zsh b/modules/completion/init.zsh
index 07acf13bf3..4cf46fa95d 100644
--- a/modules/completion/init.zsh
+++ b/modules/completion/init.zsh
@@ -32,13 +32,16 @@ unsetopt FLOW_CONTROL      # Disable start/stop characters in shell editor.
 # cache time of 20 hours, so it should almost always regenerate the first time a
 # shell is opened each day.
 autoload -Uz compinit
-_comp_files=(${ZDOTDIR:-$HOME}/.zcompdump(Nm-20))
-if (( $#_comp_files )); then
-  compinit -i -C
+_comp_path="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/zcompdump"
+# #q expands globs in conditional expressions
+if [[ $_comp_path(#qNmh-20) ]]; then
+  # -C (skip function check) implies -i (skip security check).
+  compinit -C -d "$_comp_path"
 else
-  compinit -i
+  mkdir -p "$_comp_path:h"
+  compinit -i -d "$_comp_path"
 fi
-unset _comp_files
+unset _comp_path
 
 #
 # Styles
@@ -46,7 +49,7 @@ unset _comp_files
 
 # Use caching to make completion for commands such as dpkg and apt usable.
 zstyle ':completion::complete:*' use-cache on
-zstyle ':completion::complete:*' cache-path "${ZDOTDIR:-$HOME}/.zcompcache"
+zstyle ':completion::complete:*' cache-path "${XDG_CACHE_HOME:-$HOME/.cache}/prezto/zcompcache"
 
 # Case-insensitive (all), partial-word, and then substring completion.
 if zstyle -t ':prezto:module:completion:*' case-sensitive; then
diff --git a/modules/editor/init.zsh b/modules/editor/init.zsh
index 28a2fb24a0..5b411f58a9 100644
--- a/modules/editor/init.zsh
+++ b/modules/editor/init.zsh
@@ -318,6 +318,7 @@ bindkey -M vicmd "$key_info[Control]X$key_info[Control]E" edit-command-line
 
 # Undo/Redo
 bindkey -M vicmd "u" undo
+bindkey -M viins "$key_info[Control]_" undo
 bindkey -M vicmd "$key_info[Control]R" redo
 
 if (( $+widgets[history-incremental-pattern-search-backward] )); then
diff --git a/modules/fasd/init.zsh b/modules/fasd/init.zsh
index 37babd8e3e..f948789ec8 100644
--- a/modules/fasd/init.zsh
+++ b/modules/fasd/init.zsh
@@ -19,7 +19,7 @@ fi
 # Initialization
 #
 
-cache_file="${TMPDIR:-/tmp}/prezto-fasd-cache.$UID.zsh"
+cache_file="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/fasd-cache.zsh"
 if [[ "${commands[fasd]}" -nt "$cache_file" \
       || "${ZDOTDIR:-$HOME}/.zpreztorc" -nt "$cache_file" \
       || ! -s "$cache_file"  ]]; then
@@ -31,6 +31,7 @@ if [[ "${commands[fasd]}" -nt "$cache_file" \
     init_args+=(zsh-ccomp zsh-ccomp-install zsh-wcomp zsh-wcomp-install)
   fi
 
+  mkdir -p "$cache_file:h"
   # Cache init code.
   fasd --init "$init_args[@]" >! "$cache_file" 2> /dev/null
 fi
diff --git a/modules/git/alias.zsh b/modules/git/alias.zsh
index 6d99ba8100..630db39af0 100644
--- a/modules/git/alias.zsh
+++ b/modules/git/alias.zsh
@@ -100,7 +100,9 @@ if ! zstyle -t ':prezto:module:git:alias' skip 'yes'; then
   alias gfc='git clone'
   alias gfcr='git clone --recurse-submodules'
   alias gfm='git pull'
+  alias gfma='git pull --autostash'
   alias gfr='git pull --rebase'
+  alias gfra='git pull --rebase --autostash'
 
   # Flow (F)
   alias gFi='git flow init'
@@ -191,7 +193,7 @@ if ! zstyle -t ':prezto:module:git:alias' skip 'yes'; then
   alias gls='git log --topo-order --stat --pretty=format:"${_git_log_medium_format}"'
   alias gld='git log --topo-order --stat --patch --full-diff --pretty=format:"${_git_log_medium_format}"'
   alias glo='git log --topo-order --pretty=format:"${_git_log_oneline_format}"'
-  alias glg='git log --topo-order --all --graph --pretty=format:"${_git_log_graph_format}"'
+  alias glg='git log --topo-order --all --graph --pretty=format:"${_git_log_oneline_format}"'
   alias glb='git log --topo-order --pretty=format:"${_git_log_brief_format}"'
   alias glc='git shortlog --summary --numbered'
   alias glS='git log --patch --pretty=format:"${_git_log_oneline_format}" -S'
diff --git a/modules/git/functions/git-info b/modules/git/functions/git-info
index fe8ca2acd9..20c284b08c 100644
--- a/modules/git/functions/git-info
+++ b/modules/git/functions/git-info
@@ -275,7 +275,7 @@ function git-info {
 
     # Format ahead.
     if [[ -n "$ahead_format" ]]; then
-      ahead="$ahead_and_behind[(w)1]"
+      ahead="$ahead_and_behind[(pws:\t:)1]"
       if (( ahead > 0 )); then
         zformat -f ahead_formatted "$ahead_format" "A:$ahead"
       fi
@@ -283,7 +283,7 @@ function git-info {
 
     # Format behind.
     if [[ -n "$behind_format" ]]; then
-      behind="$ahead_and_behind[(w)2]"
+      behind="$ahead_and_behind[(pws:\t:)2]"
       if (( behind > 0 )); then
         zformat -f behind_formatted "$behind_format" "B:$behind"
       fi
diff --git a/modules/gpg/init.zsh b/modules/gpg/init.zsh
index 4498b7b066..a3b37ba3bc 100644
--- a/modules/gpg/init.zsh
+++ b/modules/gpg/init.zsh
@@ -12,7 +12,7 @@ fi
 
 # Set the default paths to gpg-agent files.
 _gpg_agent_conf="${GNUPGHOME:-$HOME/.gnupg}/gpg-agent.conf"
-_gpg_agent_env="${TMPDIR:-/tmp}/gpg-agent.env.$UID"
+_gpg_agent_env="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/gpg-agent.env"
 
 # Load environment variables from previous run
 source "$_gpg_agent_env" 2> /dev/null
@@ -21,6 +21,7 @@ source "$_gpg_agent_env" 2> /dev/null
 if [[ -z "$GPG_AGENT_INFO" && ! -S "${GNUPGHOME:-$HOME/.gnupg}/S.gpg-agent" ]]; then
   # Start gpg-agent if not started.
   if ! ps -U "$LOGNAME" -o pid,ucomm | grep -q -- "${${${(s.:.)GPG_AGENT_INFO}[2]}:--1} gpg-agent"; then
+    mkdir -p "$_gpg_agent_env:h"
     eval "$(gpg-agent --daemon | tee "$_gpg_agent_env")"
   fi
 fi
diff --git a/modules/haskell/init.zsh b/modules/haskell/init.zsh
index c1c78ca2a0..cb76864122 100644
--- a/modules/haskell/init.zsh
+++ b/modules/haskell/init.zsh
@@ -10,8 +10,11 @@ if (( ! $+commands[ghc] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 # Prepend Cabal per user directories to PATH.
-if [[ "$OSTYPE" == darwin* && -d $HOME/Library/Haskell ]]; then
+if is-darwin && [[  -d $HOME/Library/Haskell ]]; then
   path=($HOME/Library/Haskell/bin(/N) $path)
 else
   path=($HOME/.cabal/bin(/N) $path)
diff --git a/modules/helper/init.zsh b/modules/helper/init.zsh
index 328bed4f71..0553556a49 100644
--- a/modules/helper/init.zsh
+++ b/modules/helper/init.zsh
@@ -29,3 +29,28 @@ function coalesce {
   done
   return 1
 }
+
+# is true on MacOS Darwin
+function is-darwin {
+  [[ "$OSTYPE" == darwin* ]]
+}
+
+# is true on Linux's
+function is-linux {
+  [[ "$OSTYPE" == linux* ]]
+}
+
+# is true on BSD's
+function is-bsd {
+  [[ "$OSTYPE" == *bsd* ]]
+}
+
+# is true on Cygwin (Windows)
+function is-cygwin {
+  [[ "$OSTYPE" == cygwin* ]]
+}
+
+# is true on termux (Android)
+function is-termux {
+  [[ "$OSTYPE" == linux-android ]]
+}
diff --git a/modules/history-substring-search/init.zsh b/modules/history-substring-search/init.zsh
index d3ee3a1131..0de78918dc 100644
--- a/modules/history-substring-search/init.zsh
+++ b/modules/history-substring-search/init.zsh
@@ -10,7 +10,9 @@
 pmodload 'editor'
 
 # Source module files.
-source "${0:h}/external/zsh-history-substring-search.zsh" || return 1
+if (( ! $+functions[history-substring-search-up] )); then
+  source "${0:h}/external/zsh-history-substring-search.zsh" || return 1
+fi
 
 #
 # Search
diff --git a/modules/homebrew/init.zsh b/modules/homebrew/init.zsh
index 9f7e0b4646..bfa667c0bc 100644
--- a/modules/homebrew/init.zsh
+++ b/modules/homebrew/init.zsh
@@ -5,8 +5,11 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+pmodload 'helper'
+
 # Return if requirements are not found.
-if [[ "$OSTYPE" != (darwin|linux)* ]]; then
+if ! is-darwin && ! is-linux; then
   return 1
 fi
 
diff --git a/modules/macports/init.zsh b/modules/macports/init.zsh
index d55744a875..7bf4ab2940 100644
--- a/modules/macports/init.zsh
+++ b/modules/macports/init.zsh
@@ -6,8 +6,11 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+pmodload 'helper'
+
 # Return if requirements are not found.
-if [[ "$OSTYPE" != darwin* ]]; then
+if ! is-darwin; then
   return 1
 fi
 
diff --git a/modules/node/init.zsh b/modules/node/init.zsh
index 1ea66f9c6c..6fb68f307d 100644
--- a/modules/node/init.zsh
+++ b/modules/node/init.zsh
@@ -39,12 +39,13 @@ typeset -A compl_commands=(
 
 for compl_command in "${(k)compl_commands[@]}"; do
   if (( $+commands[$compl_command] )); then
-    cache_file="${TMPDIR:-/tmp}/prezto-$compl_command-cache.$UID.zsh"
+    cache_file="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/$compl_command-cache.zsh"
 
     # Completion commands are slow; cache their output if old or missing.
     if [[ "$commands[$compl_command]" -nt "$cache_file" \
           || "${ZDOTDIR:-$HOME}/.zpreztorc" -nt "$cache_file" \
           || ! -s "$cache_file" ]]; then
+      mkdir -p "$cache_file:h"
       command ${=compl_commands[$compl_command]} >! "$cache_file" 2> /dev/null
     fi
 
diff --git a/modules/osx/init.zsh b/modules/osx/init.zsh
index f7871ca718..62f219437b 100644
--- a/modules/osx/init.zsh
+++ b/modules/osx/init.zsh
@@ -5,8 +5,11 @@
 #   Sorin Ionescu <sorin.ionescu@gmail.com>
 #
 
+# Load dependencies.
+pmodload 'helper'
+
 # Return if requirements are not found.
-if [[ "$OSTYPE" != darwin* ]]; then
+if ! is-darwin; then
   return 1
 fi
 
diff --git a/modules/pacman/functions/pacman-list-disowned b/modules/pacman/functions/pacman-list-disowned
index 9c8f56a0e9..c5e84fcf67 100644
--- a/modules/pacman/functions/pacman-list-disowned
+++ b/modules/pacman/functions/pacman-list-disowned
@@ -8,11 +8,11 @@
 
 # function pacman-list-disowned {
 
-local tmp="${TMPDIR:-/tmp}/pacman-disowned-$UID-$$"
+local tmp="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/pacman-disowned-$$"
 local db="$tmp/db"
 local fs="$tmp/fs"
 
-mkdir "$tmp"
+mkdir -p "$tmp"
 trap  'rm -rf "$tmp"' EXIT
 
 pacman --quiet --query --list | sort --unique > "$db"
diff --git a/modules/perl/init.zsh b/modules/perl/init.zsh
index b7a794797a..1b5e665761 100644
--- a/modules/perl/init.zsh
+++ b/modules/perl/init.zsh
@@ -10,6 +10,9 @@ if (( ! $+commands[perl] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 #
 # Load Perlbrew or plenv
 #
@@ -37,13 +40,14 @@ fi
 # Local Module Installation
 #
 
-if [[ "$OSTYPE" == darwin* ]]; then
+if is-darwin; then
   # Perl is slow; cache its output.
-  cache_file="${TMPDIR:-/tmp}/prezto-perl-cache.$UID.zsh"
+  cache_file="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/perl-cache.zsh"
   perl_path="$HOME/Library/Perl/5.12"
 
   if [[ -f "$perl_path/lib/perl5/local/lib.pm" ]]; then
     if [[ "${ZDOTDIR:-$HOME}/.zpreztorc" -nt "$cache_file" || ! -s "$cache_file" ]]; then
+      mkdir -p "$cache_file:h"
       perl -I$perl_path/lib/perl5 -Mlocal::lib=$perl_path >! "$cache_file"
     fi
 
diff --git a/modules/prompt/functions/prompt_sorin_setup b/modules/prompt/functions/prompt_sorin_setup
index 41ac7d0175..a7d341ee8d 100644
--- a/modules/prompt/functions/prompt_sorin_setup
+++ b/modules/prompt/functions/prompt_sorin_setup
@@ -54,6 +54,13 @@ function prompt_sorin_async_callback {
         zle && zle reset-prompt
       fi
       ;;
+    "[async]")
+      # Code is 1 for corrupted worker output and 2 for dead worker.
+      if [[ $2 -eq 2 ]]; then
+	  # Our worker died unexpectedly.
+          typeset -g prompt_prezto_async_init=0
+      fi
+      ;;
   esac
 }
 
diff --git a/modules/python/init.zsh b/modules/python/init.zsh
index e5967f7aa8..b878f04978 100644
--- a/modules/python/init.zsh
+++ b/modules/python/init.zsh
@@ -7,6 +7,9 @@
 #   Patrick Bos <egpbos@gmail.com>
 #
 
+# Load dependencies
+pmodload 'helper'
+
 # Load manually installed pyenv into the path
 if [[ -s "${PYENV_ROOT:=$HOME/.pyenv}/bin/pyenv" ]]; then
   path=("${PYENV_ROOT}/bin" $path)
@@ -22,7 +25,7 @@ elif (( $+commands[pyenv] )); then
 else
   if [[ -n "$PYTHONUSERBASE" ]]; then
     path=($PYTHONUSERBASE/bin $path)
-  elif [[ "$OSTYPE" == darwin* ]]; then
+  elif is-darwin; then
     path=($HOME/Library/Python/*/bin(N) $path)
   else
     # This is subject to change.
@@ -68,7 +71,7 @@ function _python-workon-cwd {
   if [[ "$ENV_NAME" != "" ]]; then
     # Activate the environment only if it is not already active
     if [[ "$VIRTUAL_ENV" != "$WORKON_HOME/$ENV_NAME" ]]; then
-      if [[ -e "$WORKON_HOME/$ENV_NAME/bin/activate" ]]; then
+      if [[ -n "$WORKON_HOME" && -e "$WORKON_HOME/$ENV_NAME/bin/activate" ]]; then
         workon "$ENV_NAME" && export CD_VIRTUAL_ENV="$ENV_NAME"
       elif [[ -e "$ENV_NAME/bin/activate" ]]; then
         source $ENV_NAME/bin/activate && export CD_VIRTUAL_ENV="$ENV_NAME"
@@ -144,17 +147,25 @@ if (( $+VIRTUALENVWRAPPER_VIRTUALENV || $+commands[virtualenv] )) && \
 fi
 
 # Load PIP completion.
-if (( $#commands[(i)pip(|[23])] )); then
-  cache_file="${TMPDIR:-/tmp}/prezto-pip-cache.$UID.zsh"
-
-  # Detect and use one available from among 'pip', 'pip2', 'pip3' variants
+# Detect and use one available from among 'pip', 'pip2', 'pip3' variants
+if [[ -n "$PYENV_ROOT" ]]; then
+  for pip in pip{,2,3}; do
+    pip_command="$(pyenv which "$pip" 2>/dev/null)"
+    [[ -n "$pip_command" ]] && break
+  done
+  unset pip
+else
   pip_command="$commands[(i)pip(|[23])]"
+fi
+if [[ -n "$pip_command" ]]; then
+  cache_file="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/pip-cache.zsh"
 
   if [[ "$pip_command" -nt "$cache_file" \
         || "${ZDOTDIR:-$HOME}/.zpreztorc" -nt "$cache_file" \
         || ! -s "$cache_file" ]]; then
+    mkdir -p "$cache_file:h"
     # pip is slow; cache its output. And also support 'pip2', 'pip3' variants
-    $pip_command completion --zsh \
+    "$pip_command" completion --zsh \
       | sed -e "s/\(compctl -K [-_[:alnum:]]* pip\).*/\1{,2,3}{,.{0..9}}/" \
       >! "$cache_file" \
       2> /dev/null
@@ -162,8 +173,9 @@ if (( $#commands[(i)pip(|[23])] )); then
 
   source "$cache_file"
 
-  unset cache_file pip_command
+  unset cache_file
 fi
+unset pip_command
 
 # Load conda into the shell session, if requested
 zstyle -T ':prezto:module:python' conda-init
diff --git a/modules/rsync/init.zsh b/modules/rsync/init.zsh
index b3010ede32..79432c1251 100644
--- a/modules/rsync/init.zsh
+++ b/modules/rsync/init.zsh
@@ -10,6 +10,9 @@ if (( ! $+commands[rsync] )); then
   return 1
 fi
 
+# Load dependencies.
+pmodload 'helper'
+
 #
 # Aliases
 #
@@ -23,7 +26,7 @@ fi
 
 # macOS and HFS+ Enhancements
 # https://bombich.com/kb/ccc5/credits
-if [[ "$OSTYPE" == darwin* ]] && grep -q 'file-flags' <(rsync --help 2>&1); then
+if is-darwin && grep -q 'file-flags' <(rsync --help 2>&1); then
   _rsync_cmd="${_rsync_cmd} --crtimes --fileflags --protect-decmpfs --force-change"
 fi
 
diff --git a/modules/ssh/init.zsh b/modules/ssh/init.zsh
index 08edce5772..b9567d4635 100644
--- a/modules/ssh/init.zsh
+++ b/modules/ssh/init.zsh
@@ -14,10 +14,10 @@ fi
 _ssh_dir="$HOME/.ssh"
 
 # Set the path to the environment file if not set by another module.
-_ssh_agent_env="${_ssh_agent_env:-${TMPDIR:-/tmp}/ssh-agent.env.$UID}"
+_ssh_agent_env="${_ssh_agent_env:-${XDG_CACHE_HOME:-$HOME/.cache}/prezto/ssh-agent.env}"
 
 # Set the path to the persistent authentication socket.
-_ssh_agent_sock="${TMPDIR:-/tmp}/ssh-agent.sock.$UID"
+_ssh_agent_sock="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/ssh-agent.sock"
 
 # Start ssh-agent if not started.
 if [[ ! -S "$SSH_AUTH_SOCK" ]]; then
@@ -26,12 +26,14 @@ if [[ ! -S "$SSH_AUTH_SOCK" ]]; then
 
   # Start ssh-agent if not started.
   if ! ps -U "$LOGNAME" -o pid,ucomm | grep -q -- "${SSH_AGENT_PID:--1} ssh-agent"; then
+    mkdir -p "$_ssh_agent_env:h"
     eval "$(ssh-agent | sed '/^echo /d' | tee "$_ssh_agent_env")"
   fi
 fi
 
 # Create a persistent SSH authentication socket.
 if [[ -S "$SSH_AUTH_SOCK" && "$SSH_AUTH_SOCK" != "$_ssh_agent_sock" ]]; then
+  mkdir -p "$_ssh_agent_sock:h"
   ln -sf "$SSH_AUTH_SOCK" "$_ssh_agent_sock"
   export SSH_AUTH_SOCK="$_ssh_agent_sock"
 fi
diff --git a/modules/utility/init.zsh b/modules/utility/init.zsh
index a2e5c2bdfe..7bb753249e 100644
--- a/modules/utility/init.zsh
+++ b/modules/utility/init.zsh
@@ -134,12 +134,16 @@ if zstyle -t ':prezto:module:utility:grep' color; then
 fi
 
 # macOS Everywhere
-if [[ "$OSTYPE" == darwin* ]]; then
+if is-darwin; then
   alias o='open'
-elif [[ "$OSTYPE" == cygwin* ]]; then
+elif is-cygwin; then
   alias o='cygstart'
   alias pbcopy='tee > /dev/clipboard'
   alias pbpaste='cat /dev/clipboard'
+elif is-termux; then
+  alias o='termux-open'
+  alias pbcopy='termux-clipboard-set'
+  alias pbpaste='termux-clipboard-get'
 else
   alias o='xdg-open'
 
@@ -166,7 +170,7 @@ fi
 alias df='df -kh'
 alias du='du -kh'
 
-if [[ "$OSTYPE" == (darwin*|*bsd*) ]]; then
+if is-darwin || is-bsd; then
   alias topc='top -o cpu'
   alias topm='top -o vsize'
 else
diff --git a/runcoms/zlogin b/runcoms/zlogin
index 9ea97929c2..ac4d3422a2 100644
--- a/runcoms/zlogin
+++ b/runcoms/zlogin
@@ -8,7 +8,7 @@
 # Execute code that does not affect the current session in the background.
 {
   # Compile the completion dump to increase startup speed.
-  zcompdump="${ZDOTDIR:-$HOME}/.zcompdump"
+  zcompdump="${XDG_CACHE_HOME:-$HOME/.cache}/prezto/zcompdump"
   if [[ -s "$zcompdump" && (! -s "${zcompdump}.zwc" || "$zcompdump" -nt "${zcompdump}.zwc") ]]; then
     zcompile "$zcompdump"
   fi