diff --git a/themes/half-life.zsh-theme b/themes/half-life.zsh-theme
index c79027ed6..c4d785126 100644
--- a/themes/half-life.zsh-theme
+++ b/themes/half-life.zsh-theme
@@ -7,31 +7,22 @@
 # git untracked files modification from Brian Carper:
 # https://briancarper.net/blog/570/git-info-in-your-zsh-prompt
 
-function virtualenv_info {
-    [ $VIRTUAL_ENV ] && echo '('`basename $VIRTUAL_ENV`') '
-}
-PR_GIT_UPDATE=1
-
-setopt prompt_subst
-
-autoload -U add-zsh-hook
-autoload -Uz vcs_info
-
 #use extended color palette if available
-if [[ $TERM = *256color* || $TERM = *rxvt* ]]; then
-    turquoise="%F{81}"
-    orange="%F{166}"
-    purple="%F{135}"
-    hotpink="%F{161}"
-    limegreen="%F{118}"
+if [[ $TERM = (*256color|*rxvt*) ]]; then
+  turquoise="%{${(%):-"%F{81}"}%}"
+  orange="%{${(%):-"%F{166}"}%}"
+  purple="%{${(%):-"%F{135}"}%}"
+  hotpink="%{${(%):-"%F{161}"}%}"
+  limegreen="%{${(%):-"%F{118}"}%}"
 else
-    turquoise="$fg[cyan]"
-    orange="$fg[yellow]"
-    purple="$fg[magenta]"
-    hotpink="$fg[red]"
-    limegreen="$fg[green]"
+  turquoise="%{${(%):-"%F{cyan}"}%}"
+  orange="%{${(%):-"%F{yellow}"}%}"
+  purple="%{${(%):-"%F{magenta}"}%}"
+  hotpink="%{${(%):-"%F{red}"}%}"
+  limegreen="%{${(%):-"%F{green}"}%}"
 fi
 
+autoload -Uz vcs_info
 # enable VCS systems you use
 zstyle ':vcs_info:*' enable git svn
 
@@ -47,10 +38,10 @@ zstyle ':vcs_info:*:prompt:*' check-for-changes true
 # %R - repository path
 # %S - path in the repository
 PR_RST="%{${reset_color}%}"
-FMT_BRANCH=" on %{$turquoise%}%b%u%c${PR_RST}"
-FMT_ACTION=" performing a %{$limegreen%}%a${PR_RST}"
-FMT_UNSTAGED="%{$orange%} ●"
-FMT_STAGED="%{$limegreen%} ●"
+FMT_BRANCH=" on ${turquoise}%b%u%c${PR_RST}"
+FMT_ACTION=" performing a ${limegreen}%a${PR_RST}"
+FMT_UNSTAGED="${orange} ●"
+FMT_STAGED="${limegreen} ●"
 
 zstyle ':vcs_info:*:prompt:*' unstagedstr   "${FMT_UNSTAGED}"
 zstyle ':vcs_info:*:prompt:*' stagedstr     "${FMT_STAGED}"
@@ -59,38 +50,44 @@ zstyle ':vcs_info:*:prompt:*' formats       "${FMT_BRANCH}"
 zstyle ':vcs_info:*:prompt:*' nvcsformats   ""
 
 
-function steeef_preexec {
-    case "$2" in
-        *git*)
-            PR_GIT_UPDATE=1
-            ;;
-        *svn*)
-            PR_GIT_UPDATE=1
-            ;;
-    esac
-}
-add-zsh-hook preexec steeef_preexec
-
 function steeef_chpwd {
-    PR_GIT_UPDATE=1
+  PR_GIT_UPDATE=1
+}
+
+function steeef_preexec {
+  case "$2" in
+  *git*|*svn*) PR_GIT_UPDATE=1 ;;
+  esac
 }
-add-zsh-hook chpwd steeef_chpwd
 
 function steeef_precmd {
-    if [[ -n "$PR_GIT_UPDATE" ]] ; then
-        # check for untracked files or updated submodules, since vcs_info doesn't
-        if [[ ! -z $(git ls-files --other --exclude-standard 2> /dev/null) ]]; then
-            PR_GIT_UPDATE=1
-            FMT_BRANCH="${PM_RST} on %{$turquoise%}%b%u%c%{$hotpink%} ●${PR_RST}"
-        else
-            FMT_BRANCH="${PM_RST} on %{$turquoise%}%b%u%c${PR_RST}"
-        fi
-        zstyle ':vcs_info:*:prompt:*' formats       "${FMT_BRANCH}"
+  (( PR_GIT_UPDATE )) || return
 
-        vcs_info 'prompt'
-        PR_GIT_UPDATE=
-    fi
+  # check for untracked files or updated submodules, since vcs_info doesn't
+  if [[ -n "$(git ls-files --other --exclude-standard 2>/dev/null)" ]]; then
+    PR_GIT_UPDATE=1
+    FMT_BRANCH="${PM_RST} on ${turquoise}%b%u%c${hotpink} ●${PR_RST}"
+  else
+    FMT_BRANCH="${PM_RST} on ${turquoise}%b%u%c${PR_RST}"
+  fi
+  zstyle ':vcs_info:*:prompt:*' formats       "${FMT_BRANCH}"
+
+  vcs_info 'prompt'
+  PR_GIT_UPDATE=
 }
-add-zsh-hook precmd steeef_precmd
 
-PROMPT=$'%{$purple%}%n%{$reset_color%} in %{$limegreen%}%~%{$reset_color%}$(ruby_prompt_info " with%{$fg[red]%} " v g "%{$reset_color%}")$vcs_info_msg_0_%{$orange%} λ%{$reset_color%} '
+# vcs_info running hooks
+PR_GIT_UPDATE=1
+
+autoload -U add-zsh-hook
+add-zsh-hook chpwd steeef_chpwd
+add-zsh-hook precmd steeef_precmd
+add-zsh-hook preexec steeef_preexec
+
+# ruby prompt settings
+ZSH_THEME_RUBY_PROMPT_PREFIX="with%F{red} "
+ZSH_THEME_RUBY_PROMPT_SUFFIX="%{$reset_color%}"
+ZSH_THEME_RVM_PROMPT_OPTIONS="v g"
+
+setopt prompt_subst
+PROMPT="${purple}%n%{$reset_color%} in ${limegreen}%~%{$reset_color%}\$(ruby_prompt_info)\$vcs_info_msg_0_${orange} λ%{$reset_color%} "