diff --git a/shell/caskroom.sh b/shell/caskroom.sh
index 84201a5..915a9be 100644
--- a/shell/caskroom.sh
+++ b/shell/caskroom.sh
@@ -2,86 +2,104 @@
 # Caskroom related stuff.
 #
 
-install_cask_global_packages () {
-  brew cask install \
-       adium-beta \
-       aerial \
-       alfred \
-       android-file-transfer \
-       appcleaner \
-       atom \
-       audio-hijack \
-       autodmg \
-       bartender \
-       betterzip \
-       bowtie \
-       calibre \
-       carbon-copy-cloner \
-       chicken \
-       cloudup \
-       daisydisk \
-       deluge \
-       discord \
-       docker-beta \
-       dropbox \
-       ethereum-wallet \
-       filebot \
-       firefox \
-       fluid \
-       flux \
-       github-desktop \
-       gog-galaxy \
-       google-cloud-sdk \
-       google-chrome \
-       gpgtools \
-       hackety-hack \
-       handbrake \
-       insomnia \
-       irccloud \
-       istat-menus \
-       istumbler \
-       iterm2 \
-       java \
-       karabiner-elements \
-       keybase \
-       licecap \
-       little-snitch \
-       logitech-options \
-       mailplane \
-       makemkv \
-       messenger \
-       micro-snitch \
-       mist \
-       moom \
-       mplayerx \
-       omnigraffle \
-       openemu \
-       parallels-desktop \
-       paw \
-       plex-media-player \
-       postman \
-       resolutionator \
-       ring \
-       screenhero \
-       sequel-pro \
-       sixtyforce \
-       skype \
-       spotify \
-       stay \
-       synology-assistant \
-       teamviewer \
-       transmission \
-       ubersicht \
-       unetbootin \
-       virtualbox \
-       virtualc64 \
-       viscosity \
-       visual-studio-code \
-       vlc \
-       vmware-fusion \
-       witgui \
-       wmail \
-       xld \
-       yakyak \
-       ynab
+bootstrap_caskroom() {
+  local pkgs=(
+    adium-beta
+    aerial
+    alfred
+    android-file-transfer
+    appcleaner
+    atom
+    audio-hijack
+    autodmg
+    bartender
+    betterzip
+    bowtie
+    calibre
+    carbon-copy-cloner
+    chicken
+    cloudup
+    daisydisk
+    deluge
+    discord
+    docker-beta
+    dropbox
+    ethereum-wallet
+    filebot
+    firefox
+    fluid
+    flux
+    github-desktop
+    gog-galaxy
+    google-cloud-sdk
+    google-chrome
+    gpgtools
+    hackety-hack
+    handbrake
+    insomnia
+    irccloud
+    istat-menus
+    istumbler
+    iterm2
+    java
+    karabiner-elements
+    keybase
+    licecap
+    little-snitch
+    logitech-options
+    mailplane
+    makemkv
+    messenger
+    micro-snitch
+    mist
+    moom
+    mplayerx
+    omnigraffle
+    openemu
+    parallels-desktop
+    paw
+    plex-media-player
+    postman
+    resolutionator
+    ring
+    screenhero
+    sequel-pro
+    sixtyforce
+    skype
+    spotify
+    stay
+    synology-assistant
+    teamviewer
+    transmission
+    ubersicht
+    unetbootin
+    virtualbox
+    virtualc64
+    viscosity
+    visual-studio-code
+    vlc
+    vmware-fusion
+    witgui
+    wmail
+    xld
+    yakyak
+    ynab
+  )
+
+  local installed=( $(brew cask list) )
+
+  for pkg in ${pkgs[@]}; do
+    local base=$(echo $pkg | awk '{print $1}')
+    local found=""
+
+    for i in ${installed[@]}; do
+      if [[ "$base" == "$i" ]]; then
+        found=1
+      fi
+    done
+
+    if [ -z "$found" ]; then
+      brew cask install "${pkg[@]}"
+    fi
+  done
 }
diff --git a/shell/homebrew.sh b/shell/homebrew.sh
index 64eddb4..e3452ff 100644
--- a/shell/homebrew.sh
+++ b/shell/homebrew.sh
@@ -2,29 +2,41 @@
 # Homebrew related stuff.
 #
 
-install_brew_global_packages () {
-  # Basic packages.
-  brew install \
-       ack \
-       android-sdk \
-       bash \
-       bazaar \
-       git \
-       heroku \
-       htop \
-       kubernetes-cli \
-       peco \
-       readline \
-       reattach-to-user-namespace \
-       the_silver_searcher \
-       tmux \
-       wget \
-       zsh
+bootstrap_homebrew () {
+  local pkgs=(
+    ack
+    "aspell --with-lang-en --with-lang-el --with-lang-sv"
+    bash
+    bazaar
+    git
+    heroku
+    htop
+    kubernetes-cli
+    mysql
+    peco
+    readline
+    reattach-to-user-namespace
+    redis
+    the_silver_searcher
+    tmux
+    wget
+    zsh
+  )
 
-  brew install aspell --with-lang-en --with-lang-el --with-lang-sv
+  local installed=( $(brew list) )
 
-  # Services.
-  brew install \
-       mysql \
-       redis
+  for pkg in ${pkgs[@]}; do
+    local base=$(echo $pkg | awk '{print $1}')
+    local found=""
+
+    for i in ${installed[@]}; do
+      if [[ "$base" == "$i" ]]; then
+        found=1
+      fi
+    done
+
+    if [ -z "$found" ]; then
+      brew install "${pkg[@]}"
+    fi
+  done
 }