diff --git a/developer/bin/develop_brew_cask b/developer/bin/develop_brew_cask
index 8e64864926..17f0943ac5 100755
--- a/developer/bin/develop_brew_cask
+++ b/developer/bin/develop_brew_cask
@@ -3,54 +3,34 @@
 # develop_brew_cask
 #
 
-set -e;              # exit on any uncaught error
-set +o histexpand;   # don't expand history expressions
+set -e;               # exit on any uncaught error
+set +o histexpand;    # don't expand history expressions
+shopt -s nocasematch; # case-insensitive regular expressions
 
-tap_subdir="Library/Taps/phinze-cask"
+cd_to_project_root () {
+    local script_dir="$(/usr/bin/dirname $0)"
+    cd "$script_dir"
+    local git_root="$(git rev-parse --show-toplevel)"
+    if [[ -z "$git_root" ]]; then
+        printf "Could not find git project root"
+        exit 1;
+    fi
+    cd "$git_root"
+}
 
-if [[ $1 =~ ^-+h(elp)?$ ]]; then
-    printf "develop_brew_cask
+cd_to_version_dir () {
+    local cellar_dir="$1"
+    local version_dir="$2"
+    if [ -z "$version_dir" ]; then
+        printf "Can't get version dir under $cellar_dir/\n";
+        exit 1;
+    fi
+    cd "$cellar_dir/$version_dir"
+}
 
-   Symlink private repo directories into Homebrew's Cellar, so
-   that the 'brew cask' command will use the current development
-   branch in your private repo.
-
-   Saves the production Homebrew directories under new names.
-
-   You can reverse this operation with 'production_brew_cask'.
-
-   Note: it is not safe to run 'brew update' while development
-   mode is in effect.
-
-"
-    exit
-fi
-
-script_dir="$(/usr/bin/dirname $0)"
-cd "$script_dir"
-
-git_root="$(git rev-parse --show-toplevel)"
-brew_prefix="$(brew --prefix)"
-cellar_dir="$brew_prefix/Cellar/brew-cask"
-version_dir=$(/bin/ls "$cellar_dir/" | sort | tail -1)
-tap_dir="$brew_prefix/$tap_subdir"
-
-# sanity check
-if [[ $(/usr/bin/stat -L -f '%i' "$tap_dir") -eq $(/usr/bin/stat -L -f '%i' "$git_root") ]]; then
-    printf "\nERROR: run this script in your private repo, not inside Homebrew.\n"
-    exit 1;
-fi
-
-if [ -z "$version_dir" ]; then
-    echo "Can't get version dir under $cellar_dir/"
-    exit 1;
-fi
-cd "$cellar_dir/$version_dir"
-
-if [ -e "production_rubylib" ]; then
-    echo "brew-cask is already set up for development"
-    exit 1
-else
+create_dev_links () {
+    local git_root="$1"
+    local tap_dir="$2"
     mv rubylib production_rubylib
     mv Casks   production_Casks
     ln -s "$git_root/Casks" .
@@ -60,10 +40,58 @@ else
     mv Casks production_Casks
     ln -s "$git_root/Casks" .
     ln -s "$git_root/lib"   .
+}
 
-    echo "brew-cask is now in development mode"
-    echo "Note: it is not safe 'brew update' while in development mode"
+_develop_brew_cask () {
 
+    # configurable
+    local tap_subdir="Library/Taps/phinze-cask"
+
+    # initialization
+    cd_to_project_root;
+    local git_root=`pwd`
+    local brew_prefix="$(brew --prefix)"
+    local cellar_dir="$brew_prefix/Cellar/brew-cask"
+    local version_dir=$(/bin/ls "$cellar_dir/" | sort | tail -1)
+    local tap_dir="$brew_prefix/$tap_subdir"
+
+    # sanity check
+    if [[ $(/usr/bin/stat -L -f '%i' "$tap_dir") -eq $(/usr/bin/stat -L -f '%i' "$git_root") ]]; then
+        printf "\nERROR: run this script in your private repo, not inside Homebrew.\n";
+        exit 1;
+    fi
+
+    # action
+    cd_to_version_dir "$cellar_dir" "$version_dir";
+    if [ -e "production_rubylib" ]; then
+        printf "brew-cask is already set up for development\n";
+        exit 1
+    else
+        create_dev_links "$git_root" "$tap_dir";
+        printf "brew-cask is now in development mode\n"
+        printf "Note: it is not safe to run 'brew update' while in development mode\n"
+    fi
+
+}
+
+if [[ $1 =~ ^-+h(elp)?$ ]]; then
+    printf "develop_brew_cask
+
+Symlink private repo directories into Homebrew's Cellar, so
+that the 'brew cask' command will use the current development
+branch in your private repo.
+
+Saves the production Homebrew directories under new names.
+
+You can reverse this operation with 'production_brew_cask'.
+
+Note: it is not safe to run 'brew update' while development
+mode is in effect.
+
+"
+    exit
 fi
 
+_develop_brew_cask "$@";
+
 #
diff --git a/developer/bin/extract_pkg_ids b/developer/bin/extract_pkg_ids
index 9e900bf1f5..a801f465d7 100755
--- a/developer/bin/extract_pkg_ids
+++ b/developer/bin/extract_pkg_ids
@@ -26,29 +26,29 @@ _extract_pkg_ids () {
 }
 
 if [[ $1 =~ ^-+h(elp)?$ || -z "$1" ]]; then
-   printf "extract_pkg_ids <file.pkg>
+    printf "extract_pkg_ids <file.pkg>
 
-    Given a package file, extract a list of candidate Package IDs
-    which may be useful in a Cask uninstall stanza, eg
+Given a package file, extract a list of candidate Package IDs
+which may be useful in a Cask uninstall stanza, eg
 
-        uninstall :pkgutil => 'package.id.goes.here'
+    uninstall :pkgutil => 'package.id.goes.here'
 
-    The given package file need not be installed.
+The given package file need not be installed.
 
-    The output of this script should be overly inclusive -- not
-    every candidate package id in the output will be needed at
-    uninstall time.
+The output of this script should be overly inclusive -- not
+every candidate package id in the output will be needed at
+uninstall time.
 
-    Package IDs designated by Apple or the Sparkle framework will
-    be omitted.
+Package IDs designated by Apple or the Sparkle framework will
+be omitted.
 
-    If a package id is already installed, it will be followed by
-    a plus symbol '(+)' in the output.  This can be verified via
-    the command
+If a package id is already installed, it will be followed by
+a plus symbol '(+)' in the output.  This can be verified via
+the command
 
-        /usr/sbin/pkgutil --pkg-info 'package.id.goes.here'
+    /usr/sbin/pkgutil --pkg-info 'package.id.goes.here'
 
-    See CONTRIBUTING.md and 'man pkgutil' for more information.
+See CONTRIBUTING.md and 'man pkgutil' for more information.
 
 "
     exit
diff --git a/developer/bin/production_brew_cask b/developer/bin/production_brew_cask
index c6b8ef37f2..42729d097a 100755
--- a/developer/bin/production_brew_cask
+++ b/developer/bin/production_brew_cask
@@ -3,46 +3,33 @@
 # production_brew_cask
 #
 
-set -e;              # exit on any uncaught error
-set +o histexpand;   # don't expand history expressions
+set -e;               # exit on any uncaught error
+set +o histexpand;    # don't expand history expressions
+shopt -s nocasematch; # case-insensitive regular expressions
 
-tap_subdir="Library/Taps/phinze-cask"
+cd_to_project_root () {
+    local script_dir="$(/usr/bin/dirname $0)"
+    cd "$script_dir"
+    local git_root="$(git rev-parse --show-toplevel)"
+    if [[ -z "$git_root" ]]; then
+        printf "Could not find git project root"
+        exit 1;
+    fi
+    cd "$git_root"
+}
 
-if [[ $1 =~ ^-+h(elp)?$ ]]; then
-    printf "production_brew_cask
+cd_to_version_dir () {
+    local cellar_dir="$1"
+    local version_dir="$2"
+    if [ -z "$version_dir" ]; then
+        printf "Can't get version dir under $cellar_dir/\n";
+        exit 1;
+    fi
+    cd "$cellar_dir/$version_dir"
+}
 
-   Undo all symlinks created by 'develop_brew_cask' so that
-   the 'brew cask' command will use only released code within
-   Homebrew.
-
-   After running this command it is safe to run 'brew update'.
-
-"
-    exit
-fi
-
-script_dir="$(/usr/bin/dirname $0)"
-cd "$script_dir"
-
-git_root="$(git rev-parse --show-toplevel)"
-brew_prefix="$(brew --prefix)"
-cellar_dir="$brew_prefix/Cellar/brew-cask"
-version_dir=$(/bin/ls "$cellar_dir/" | sort | tail -1)
-tap_dir="$brew_prefix/$tap_subdir"
-
-# sanity check
-if [[ $(/usr/bin/stat -L -f '%i' "$tap_dir") -eq $(/usr/bin/stat -L -f '%i' "$git_root") ]]; then
-    printf "\nERROR: run this script in your private repo, not inside Homebrew.\n"
-    exit 1;
-fi
-
-if [ -z "$version_dir" ]; then
-    echo "Can't get version dir under $cellar_dir/"
-    exit 1;
-fi
-cd "$cellar_dir/$version_dir"
-
-if [ -e "production_rubylib" ]; then
+remove_dev_links () {
+    local tap_dir="$1"
     rm rubylib Casks
     mv production_rubylib rubylib
     mv production_Casks   Casks
@@ -50,11 +37,53 @@ if [ -e "production_rubylib" ]; then
     rm lib Casks
     mv production_lib   lib
     mv production_Casks Casks
-    echo "brew-cask is now in production mode"
-    echo "It is safe to run 'brew update'"
-else
-    echo "brew-cask is already set up for production"
-    exit 1
+}
+
+_production_brew_cask () {
+
+    # configurable
+    local tap_subdir="Library/Taps/phinze-cask"
+
+    # initialization
+    cd_to_project_root;
+    local git_root=`pwd`
+    local brew_prefix="$(brew --prefix)"
+    local cellar_dir="$brew_prefix/Cellar/brew-cask"
+    local version_dir=$(/bin/ls "$cellar_dir/" | sort | tail -1)
+    local tap_dir="$brew_prefix/$tap_subdir"
+
+    # sanity check
+    if [[ $(/usr/bin/stat -L -f '%i' "$tap_dir") -eq $(/usr/bin/stat -L -f '%i' "$git_root") ]]; then
+        printf "\nERROR: run this script in your private repo, not inside Homebrew.\n"
+        exit 1;
+    fi
+
+    # action
+    cd_to_version_dir "$cellar_dir" "$version_dir";
+    if [ -e "production_rubylib" ]; then
+        remove_dev_links "$tap_dir";
+        printf "brew-cask is now in production mode\n"
+        printf "It is safe to run 'brew update'\n"
+    else
+        printf "brew-cask is already set up for production\n"
+        exit 1
+    fi
+
+}
+
+if [[ $1 =~ ^-+h(elp)?$ ]]; then
+    printf "production_brew_cask
+
+Undo all symlinks created by 'develop_brew_cask' so that
+the 'brew cask' command will use only released code within
+Homebrew.
+
+After running this command it is safe to run 'brew update'.
+
+"
+    exit
 fi
 
+_production_brew_cask "$@";
+
 #
diff --git a/developer/bin/project_stats b/developer/bin/project_stats
index ab7ad5fb87..a61915bfab 100755
--- a/developer/bin/project_stats
+++ b/developer/bin/project_stats
@@ -5,98 +5,113 @@
 # stats on project/release from git database
 #
 
-set -e                # exit on any uncaught error
-set +o histexpand     # don't expand history expressions
-shopt -s nocasematch
+set -e;               # exit on any uncaught error
+set +o histexpand;    # don't expand history expressions
+shopt -s nocasematch; # case-insensitive regular expressions
 
-start_object="5a0d1d5556e3f963a0d34da46e16ecffa59ea2fc" # initial commit
-end_object="HEAD"
+cd_to_project_root () {
+    local script_dir="$(/usr/bin/dirname $0)"
+    cd "$script_dir"
+    local git_root="$(git rev-parse --show-toplevel)"
+    if [[ -z "$git_root" ]]; then
+        printf "Could not find git project root"
+        exit 1;
+    fi
+    cd "$git_root"
+}
 
-# these paths relative to project root
-cask_paths="Casks"
-code_paths="bin developer lib test brew-cask.rb Rakefile Gemfile Gemfile.lock"
-doc_paths="LICENSE *.md"
+warn_if_off_branch () {
+    local branch="$(git rev-parse --abbrev-ref HEAD)"
+    local wanted_branch='master'
+    if [[ -n "$1" ]]; then
+        wanted_branch="$1"
+    fi
+    if [[ "$branch" != "$wanted_branch" ]]; then
+        printf "\nWARNING: you are running from branch '$branch', not '$wanted_branch'\n\n"
+    fi
+}
 
-# cd to project root
-script_dir="$(/usr/bin/dirname $0)"
-cd "$script_dir"
-git_root="$(git rev-parse --show-toplevel)"
-cd "$git_root"
+verify_git_object () {
+    if ! git rev-parse --verify "$1" > /dev/null 2>/dev/null; then
+        printf "\nERROR: No such commit object: $1\n\n"
+        exit 1
+    fi
+}
 
-# remember initial commit hash
-git_log_alltime="git log --format='%ae' ${start_object}..${end_object}"
+_homebrew_cask_project_stats () {
 
-###
-### main
-###
+    local initial_commit="5a0d1d5556e3f963a0d34da46e16ecffa59ea2fc"
+    local start_object="$initial_commit"
+    local end_object="HEAD"
+
+    # these paths relative to project root
+    local cask_paths="Casks"
+    local code_paths="bin developer lib test brew-cask.rb Rakefile Gemfile Gemfile.lock"
+    local doc_paths="LICENSE *.md"
+
+    cd_to_project_root;
+    warn_if_off_branch 'master';
+
+    if [[ "$1" = 'release' ]]; then
+        start_object="$(git describe --tags --abbrev=0)"
+    elif [[ -n "$1" ]]; then
+        start_object="$1"
+    fi
+    verify_git_object "$start_object";
+
+    printf "Unique contributors"
+    if [[ "$start_object" != "$initial_commit" ]]; then
+        printf " since $start_object"
+    fi
+    printf "\n"
+
+    local git_log_cmd="git log --format='%ae' ${start_object}..${end_object}"
+
+    local cask_authors="$($git_log_cmd -- $cask_paths | sort | uniq | wc -l)"
+    printf "  Casks\t$cask_authors\n"
+    printf "  code\t"
+    $git_log_cmd -- $code_paths | sort | uniq | wc -l
+    printf "  docs\t"
+    $git_log_cmd -- $doc_paths  | sort | uniq | wc -l
+    printf "  any\t"
+    $git_log_cmd -- .           | sort | uniq | wc -l
+    if [[ "$start_object" != "$initial_commit" ]]; then
+        printf "\nAll-time contributors\t"
+        git log --format='%ae' ${initial_commit}..${end_object} -- . | sort | uniq | wc -l
+    fi
+
+    printf "\n"
+
+    if [[ "$start_object" != "$initial_commit" ]]; then
+        local new_casks="$(git diff --name-status "$start_object" "$end_object" -- $cask_paths | /usr/bin/grep '^A.*\.rb' | cut -f2 | sort | uniq | wc -l)"
+        local updated_casks="$(git diff --name-status "$start_object" "$end_object" -- $cask_paths | /usr/bin/grep '^M.*\.rb' | cut -f2 | sort | uniq | wc -l)"
+        # arithmetic removes whitespace
+        ((cask_authors  += 0))
+        ((new_casks     += 0))
+        ((updated_casks += 0))
+        printf "$new_casks Casks added ($updated_casks updated) by $cask_authors contributors since $start_object\n"
+    fi
+
+    printf "Total current Casks in HEAD\t"
+    find $cask_paths -name '*.rb' | wc -l
+
+}
 
 if [[ $1 =~ ^-+h(elp)?$ ]]; then
-    printf "project_stats
+    printf "project_stats [ <commit-object> ]
 
-Usage:
+With optional single argument, (eg a tag or commit-hash)
+show statistics since that commit object.
 
-   project_stats [ <commit-object> ]
+Use the special argument 'release' to calculate since the
+most recent tag (usually the same as the last release).
 
-   With optional single argument, (eg a tag or commit-hash)
-   show statistics since that commit object.
-
-   Use the special argument 'release' to calculate since the
-   most recent tag (usually the same as the last release).
-
-   Without argument, show statistics since first commit.
+Without argument, show statistics since first commit.
 
 "
     exit
 fi
 
-branch="$(git rev-parse --abbrev-ref HEAD)"
-if [[ "$branch" != "master" ]]; then
-    printf "\nWARNING: you are running from branch '$branch', not 'master'\n\n"
-fi
-
-printf "Unique contributors"
-if [[ "$1" = 'release' ]]; then
-    start_object="$(git describe --tags --abbrev=0)"
-    printf " since $start_object"
-elif [[ -n "$1" ]]; then
-    start_object="$1"
-    printf " since $start_object"
-fi
-printf "\n"
-
-if ! git rev-parse --verify "$start_object" > /dev/null 2>/dev/null; then
-    printf "\nERROR: No such commit object: $start_object\n\n"
-    exit 1
-fi
-
-git_log="git log --format='%ae' ${start_object}..${end_object}"
-
-cask_authors="$($git_log -- $cask_paths | sort | uniq | wc -l)"
-printf "  Casks\t$cask_authors\n"
-
-printf "  code\t"
-$git_log -- $code_paths | sort | uniq | wc -l
-printf "  docs\t"
-$git_log -- $doc_paths  | sort | uniq | wc -l
-printf "  any\t"
-$git_log -- .           | sort | uniq | wc -l
-if [[ -n "$1" ]]; then
-    printf "\nAll-time contributors\t"
-    $git_log_alltime -- . | sort | uniq | wc -l
-fi
-
-printf "\n"
-
-if [[ -n "$1" ]]; then
-    new_casks="$(git diff --name-status "$start_object" "$end_object" -- $cask_paths | /usr/bin/grep '^A.*\.rb' | cut -f2 | sort | uniq | wc -l)"
-    updated_casks="$(git diff --name-status "$start_object" "$end_object" -- $cask_paths | /usr/bin/grep '^M.*\.rb' | cut -f2 | sort | uniq | wc -l)"
-    ((cask_authors  += 0))
-    ((new_casks     += 0))
-    ((updated_casks += 0))
-    printf "$new_casks Casks added ($updated_casks updated) by $cask_authors contributors since $start_object\n"
-fi
-
-printf "Total current Casks in HEAD\t"
-find $cask_paths -name '*.rb' | wc -l
+_homebrew_cask_project_stats "$@";
 
 #