diff --git a/bash/ansi_colors b/bash/ansi_colors
new file mode 100644
index 0000000..d90080d
--- /dev/null
+++ b/bash/ansi_colors
@@ -0,0 +1,36 @@
+local NONE="\[\033[0m\]"    # unsets color to term's fg color
+
+# regular colors
+local K="\[\033[0;30m\]"    # black
+local R="\[\033[0;31m\]"    # red
+local G="\[\033[0;32m\]"    # green
+local Y="\[\033[0;33m\]"    # yellow
+local B="\[\033[0;34m\]"    # blue
+local M="\[\033[0;35m\]"    # magenta
+local C="\[\033[0;36m\]"    # cyan
+local W="\[\033[0;37m\]"    # white
+
+# emphasized (bolded) colors
+local EMK="\[\033[1;30m\]"
+local EMR="\[\033[1;31m\]"
+local EMG="\[\033[1;32m\]"
+local EMY="\[\033[1;33m\]"
+local EMB="\[\033[1;34m\]"
+local EMM="\[\033[1;35m\]"
+local EMC="\[\033[1;36m\]"
+local EMW="\[\033[1;37m\]"
+
+# background colors
+local BGK="\[\033[40m\]"
+local BGR="\[\033[41m\]"
+local BGG="\[\033[42m\]"
+local BGY="\[\033[43m\]"
+local BGB="\[\033[44m\]"
+local BGM="\[\033[45m\]"
+local BGC="\[\033[46m\]"
+local BGW="\[\033[47m\]"
+
+local UC=$W                 # user's color
+[ $UID -eq "0" ] && UC=$R   # root's color
+
+# vim: ft=sh
diff --git a/bash/profile b/bash/profile
index 0992b07..c649c97 100644
--- a/bash/profile
+++ b/bash/profile
@@ -1,13 +1,14 @@
-## bash_profile
+## bash_profile, called for login shells
 
-# handle .profile too
-. ~/.profile
+# dotfiles locations
+DOTFILES_HOME_DIR="$(cd -P "$(dirname "$(readlink ${BASH_SOURCE[0]})")" && pwd)"
+DOTFILES_ROOT_DIR="$( dirname "$DOTFILES_HOME_DIR" )"
+DOTFILES_BASH_DIR="$DOTFILES_ROOT_DIR/bash"
 
-# homebrew bash autocompletion
-if [ -f `brew --prefix`/etc/bash_completion ]; then
-  . `brew --prefix`/etc/bash_completion
-fi
+# include .profile
+source ~/.profile
 
-# execute bashrc
-[ -n "$BASH" ] && . ~/.bashrc
+# include bashrc too if this is an interactive shell
+[[ $- == *i* ]] && source ~/.bashrc
 
+# vim: ft=sh
diff --git a/bash/prompt b/bash/prompt
index d8c3ff1..a508fd5 100644
--- a/bash/prompt
+++ b/bash/prompt
@@ -32,15 +32,15 @@ __tpwd() {
     __truncate_dir "$PWD"
 }
 
-bash_prompt_command() {
+__bash_prompt_command() {
     local pwdmaxlen=25
     local trunc_symbol="…"
 
-    NEW_PWD=$(__tpwd)
+    PROMPT_PWD=$(__tpwd)
 }
 
 
-bash_prompt() {
+__set_bash_ps1() {
     case $TERM in
      xterm*|rxvt*)
          local TITLEBAR='\[\033]0;\u:${NEW_PWD}\007\]'
@@ -49,50 +49,19 @@ bash_prompt() {
          local TITLEBAR=""
           ;;
     esac
-    local NONE="\[\033[0m\]"    # unsets color to term's fg color
-    
-    # regular colors
-    local K="\[\033[0;30m\]"    # black
-    local R="\[\033[0;31m\]"    # red
-    local G="\[\033[0;32m\]"    # green
-    local Y="\[\033[0;33m\]"    # yellow
-    local B="\[\033[0;34m\]"    # blue
-    local M="\[\033[0;35m\]"    # magenta
-    local C="\[\033[0;36m\]"    # cyan
-    local W="\[\033[0;37m\]"    # white
-    
-    # emphasized (bolded) colors
-    local EMK="\[\033[1;30m\]"
-    local EMR="\[\033[1;31m\]"
-    local EMG="\[\033[1;32m\]"
-    local EMY="\[\033[1;33m\]"
-    local EMB="\[\033[1;34m\]"
-    local EMM="\[\033[1;35m\]"
-    local EMC="\[\033[1;36m\]"
-    local EMW="\[\033[1;37m\]"
-    
-    # background colors
-    local BGK="\[\033[40m\]"
-    local BGR="\[\033[41m\]"
-    local BGG="\[\033[42m\]"
-    local BGY="\[\033[43m\]"
-    local BGB="\[\033[44m\]"
-    local BGM="\[\033[45m\]"
-    local BGC="\[\033[46m\]"
-    local BGW="\[\033[47m\]"
-    
-    local UC=$W                 # user's color
-    [ $UID -eq "0" ] && UC=$R   # root's color
-    
+
+    # load color vars
+    source "$DOTFILES_BASH_DIR/ansi_colors"
+
     # colorized:
-    PS1="${TITLEBAR} ${EMC}[${UC}\u${EMC}@${UC}\h ${EMB}\${NEW_PWD}${EMC}]${UC}\\$ ${NONE}"
+    PS1="${TITLEBAR} ${B}[${UC}\u@\h ${G}\${PROMPT_PWD}${B}]${UC}\\$ ${NONE}"
     # without colors:
     #PS1="${TITLEBAR}[\u@\h \${NEW_PWD}]\\$ "
     # extra backslash in front of \$ to make bash colorize the prompt
 }
 
-PROMPT_COMMAND=bash_prompt_command
-bash_prompt
-unset bash_prompt
+PROMPT_COMMAND=__bash_prompt_command
+__set_bash_ps1
+unset __set_bash_ps1
 
-# vim: set filetype=sh :
+# vim: ft=sh
diff --git a/bash/rc b/bash/rc
index e71e45a..b4744dd 100644
--- a/bash/rc
+++ b/bash/rc
@@ -1,19 +1,24 @@
-## bashrc
+## bashrc, called for interactive shells
 
 # set a nice prompt
-source ~/.dotfiles/bash/prompt
+source $DOTFILES_BASH_DIR/prompt
 
 # ignore repeated, space-started, and casual commands
 export HISTIGNORE="&:[ ]*:l[sl]:[bf]g:exit"
 
 # enable multiline single command
 shopt -s cmdhist
+
 # enable appending to histfile
 shopt -s histappend
 shopt -s cdspell
 
-# turn off bells
+# turn off distractive bells
 set bell-style none
 
-#source ~/.aliases
+# homebrew bash autocompletion
+if [ -f `brew --prefix`/etc/bash_completion ]; then
+  source `brew --prefix`/etc/bash_completion
+fi
 
+# vim: ft=sh
diff --git a/zsh/profile b/zsh/profile
index 9bd9d8b..b656220 100644
--- a/zsh/profile
+++ b/zsh/profile
@@ -1,4 +1,14 @@
+# zprofile, called for login shells
+
+# dotfiles locations
+DOTFILES_HOME_DIR="$(cd -P "$(dirname "$(readlink ~/.zprofile)")" && pwd)"
+DOTFILES_ROOT_DIR="$( dirname "$DOTFILES_HOME_DIR" )"
+DOTFILES_ZSH_DIR="$DOTFILES_ROOT_DIR/zsh"
+
 emulate sh
-. ~/.profile
+source ~/.profile
 emulate zsh
 
+# zshrc will be called automatically for interactive shells
+
+# vim: ft=zsh
diff --git a/zsh/rc b/zsh/rc
index 0e69be1..0356a99 100644
--- a/zsh/rc
+++ b/zsh/rc
@@ -1,5 +1,6 @@
-# Set up the prompt
+# zshrc, called for interactive shells
 
+# Set up the prompt
 
 # Set terminal title
 set_term_title() {
@@ -139,3 +140,4 @@ chpwd() {
     set_term_title
 }
 
+# vim: ft=zsh