diff --git a/.rultor.yml b/.rultor.yml
index bd16c4c27..2a2b445e8 100644
--- a/.rultor.yml
+++ b/.rultor.yml
@@ -5,4 +5,4 @@ install:
     - git submodule update
     - locale
     - ./build/install.sh
-    - ./build.sh
+    - ./build/build.sh
diff --git a/.travis.yml b/.travis.yml
index ce9ce2a1c..d352435d3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,6 @@ language: bash
 install:
   - ./build/install.sh
 script:
-  - ./build.sh
+  - ./build/build.sh
 notifications:
   email: false
diff --git a/README.md b/README.md
index b99559641..ad6b8ec64 100644
--- a/README.md
+++ b/README.md
@@ -130,6 +130,10 @@ If you're brand-new to the project and run into any blockers, please
 [open an issue](https://github.com/caarlos0/dotfiles/issues) on this repository
 and I'd love to get it fixed for you!
 
+## known issues
+
+- All SC2039 ignores should be fixed (#65);
+
 ## contributing
 
 Feel free to contribute. Pull requests will be automatically
diff --git a/antigen/install.sh b/antigen/install.sh
index a572890ff..6c5544c98 100755
--- a/antigen/install.sh
+++ b/antigen/install.sh
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 touch ~/.z
diff --git a/antigen/path.zsh b/antigen/path.zsh
index 143a0921d..cca254e6d 100644
--- a/antigen/path.zsh
+++ b/antigen/path.zsh
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 source "$ZSH/antigen/antigen/antigen.zsh"
diff --git a/atom.symlink/install.sh b/atom.symlink/install.sh
index fd4187553..bcf29f02e 100755
--- a/atom.symlink/install.sh
+++ b/atom.symlink/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" = "Darwin" ] && brew cask install atom
 apm install \
   editorconfig autocomplete-plus \
diff --git a/bin/dot b/bin/dot
index dba7ebf40..e953c2c03 100755
--- a/bin/dot
+++ b/bin/dot
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 #
 # dot
 #
@@ -6,13 +6,14 @@
 # to make sure you're on the latest and greatest.
 main() {
   cd ~/.dotfiles
+  # shellcheck disable=SC2155
   export ZSH="$(pwd)"
   echo "Updating dotfiles..."
   git pull origin master
 
   echo "Updating antigen plugins..."
   git submodule update
-  source ./antigen/antigen/antigen.zsh
+  . ./antigen/antigen/antigen.zsh
   antigen apply
   antigen update
 
diff --git a/bin/e b/bin/e
index 5a4f4edc5..67d54e4d9 100755
--- a/bin/e
+++ b/bin/e
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 #
 # Quick shortcut to an editor.
 #
diff --git a/bin/git-add-rm-line-count b/bin/git-add-rm-line-count
index 664ec7fb7..9cbd4ce03 100755
--- a/bin/git-add-rm-line-count
+++ b/bin/git-add-rm-line-count
@@ -1,9 +1,10 @@
 #!/bin/bash
 set -eo pipefail
 add_rm_lc() {
-  local diff_result=$(git diff)
-  local added=$(echo "$diff_result" | grep -c '^+')
-  local deleted=$(echo "$diff_result" | grep -c '^-')
+  local diff_result added deleted
+  diff_result=$(git diff)
+  added=$(echo "$diff_result" | grep -c '^+')
+  deleted=$(echo "$diff_result" | grep -c '^-')
   echo "${added} additions and ${deleted} deletions."
 }
 add_rm_lc "$@"
diff --git a/bin/killport b/bin/killport
index 63cb40d2f..f9a2f9b30 100755
--- a/bin/killport
+++ b/bin/killport
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 kill -9 "$(lsof -i tcp:"$1" | head -n 2 | tail -n 1 | awk '{print $2}')"
diff --git a/bin/lsopenports b/bin/lsopenports
index 99bd2c085..627289084 100755
--- a/bin/lsopenports
+++ b/bin/lsopenports
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 lsof -i -n -P
diff --git a/build b/build
index 1df67b25d..c568d592d 160000
--- a/build
+++ b/build
@@ -1 +1 @@
-Subproject commit 1df67b25da1a5742c73ba7f9653de34dbe5af2b9
+Subproject commit c568d592d88305fe0638cf28b3965b95fe75510f
diff --git a/build.sh b/build.sh
deleted file mode 100755
index 305b70f68..000000000
--- a/build.sh
+++ /dev/null
@@ -1,4 +0,0 @@
-#!/usr/bin/env bash
-set -eo pipefail
-source ./build/build.sh
-check "./zsh/zshrc.symlink"
diff --git a/docker/install.sh b/docker/install.sh
index 5e8b39b64..0ab190225 100755
--- a/docker/install.sh
+++ b/docker/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 if [ "$(uname -s)" = "Darwin" ]; then
   brew cask install kitematic
 fi
diff --git a/docker/path.zsh b/docker/path.zsh
index 2347aa30e..808b54215 100755
--- a/docker/path.zsh
+++ b/docker/path.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 reload-docker() {
   eval "$(docker-machine env dev)"
 }
diff --git a/functions/c b/functions/c
index ec71d8fcb..1f913f723 100755
--- a/functions/c
+++ b/functions/c
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 cd "$PROJECTS/$1"
diff --git a/functions/d b/functions/d
index e03ae0e7c..7faf84b30 100755
--- a/functions/d
+++ b/functions/d
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 cd "$ZSH/$1"
diff --git a/functions/extract b/functions/extract
index 72ccc2858..23c298fe2 100755
--- a/functions/extract
+++ b/functions/extract
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 # credit: http://nparikh.org/notes/zshrc.txt
 # Usage: extract <file>
 # Description: extracts archived files / mounts disk images
@@ -25,4 +25,3 @@ extract () {
         echo "'$1' is not a valid file"
     fi
 }
-
diff --git a/functions/h b/functions/h
index 23f752462..7060e5fc7 100755
--- a/functions/h
+++ b/functions/h
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 cd "$HOME/$1"
diff --git a/functions/server b/functions/server
index 61550bc13..a817e815c 100755
--- a/functions/server
+++ b/functions/server
@@ -1,5 +1,5 @@
-#!/bin/zsh
-function server {
+#!/bin/sh
+server() {
   local port="${1-8000}"
   python -m SimpleHTTPServer "$port" &
   open "http://localhost:$port"
diff --git a/git/aliases.zsh b/git/aliases.zsh
index e391dd176..911d8a0f7 100755
--- a/git/aliases.zsh
+++ b/git/aliases.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 alias gl='git pull --prune'
 alias glg="git log --graph --decorate --oneline --abbrev-commit"
 alias gp='git push origin HEAD'
diff --git a/git/install.sh b/git/install.sh
index 6cb9f4d8d..6c1d18541 100755
--- a/git/install.sh
+++ b/git/install.sh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 brew install git
diff --git a/golang/install.sh b/golang/install.sh
index 88437808a..588a1586a 100755
--- a/golang/install.sh
+++ b/golang/install.sh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 brew install go
diff --git a/golang/path.zsh b/golang/path.zsh
index c7c798966..27927d338 100755
--- a/golang/path.zsh
+++ b/golang/path.zsh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 export GOPATH="$PROJECTS/Go"
 [ ! -d "$GOPATH" ] &&  mkdir -p "$GOPATH"
diff --git a/homebrew/aliases.zsh b/homebrew/aliases.zsh
index f3fb3f84a..0991a2e16 100755
--- a/homebrew/aliases.zsh
+++ b/homebrew/aliases.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 brewbump() {
   brew update
   brew upgrade --all
diff --git a/homebrew/install.sh b/homebrew/install.sh
index 1a726725d..f4f2142ed 100755
--- a/homebrew/install.sh
+++ b/homebrew/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 #
 # Homebrew
 #
diff --git a/java/aliases.zsh b/java/aliases.zsh
index 0ace1cd11..9a9f14251 100755
--- a/java/aliases.zsh
+++ b/java/aliases.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 
 mvn() {
   # shellcheck disable=SC2068
diff --git a/java/install.sh b/java/install.sh
index c985814d4..38fb2abfc 100755
--- a/java/install.sh
+++ b/java/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 
 # install some java stuff
diff --git a/java/path.zsh b/java/path.zsh
index 5a1c4ff04..82dd7019c 100755
--- a/java/path.zsh
+++ b/java/path.zsh
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 export MAVEN_OPTS="-Xmx1024m"
diff --git a/node/aliases.zsh b/node/aliases.zsh
index 7e69f06c3..3f17880a7 100755
--- a/node/aliases.zsh
+++ b/node/aliases.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 alias npis='npm install --save'
 alias npisd='npm install --save-dev'
 alias npig='npm install -g'
diff --git a/node/install.sh b/node/install.sh
index 61de0f75b..a33ffe7bb 100755
--- a/node/install.sh
+++ b/node/install.sh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 brew install node
diff --git a/node/path.zsh b/node/path.zsh
index 241a213ff..c27fa78e2 100755
--- a/node/path.zsh
+++ b/node/path.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 export PATH="/usr/local/share/npm/bin:$PATH"
 export PATH="$PATH:$HOME/.npm/bin"
 
diff --git a/postgres/path.zsh b/postgres/path.zsh
index 11563bce6..c4c722237 100755
--- a/postgres/path.zsh
+++ b/postgres/path.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
-if [[ "$(uname -s)" = "Darwin" ]]; then
+#!/bin/sh
+if [ "$(uname -s)" = "Darwin" ]; then
   export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.4/bin
 fi
diff --git a/ruby/aliases.zsh b/ruby/aliases.zsh
index 9b9e36a47..eb368def1 100755
--- a/ruby/aliases.zsh
+++ b/ruby/aliases.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 alias migrate='rake db:migrate'
 alias fs='bundle exec foreman start'
 alias fsdev='bundle exec foreman start -f Procfile.dev'
diff --git a/ruby/install.sh b/ruby/install.sh
index ab262ec08..03a124c66 100755
--- a/ruby/install.sh
+++ b/ruby/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 
 if test ! "$(which rbenv)"; then
diff --git a/ruby/path.zsh b/ruby/path.zsh
index db1bb3e94..f646be575 100755
--- a/ruby/path.zsh
+++ b/ruby/path.zsh
@@ -1,7 +1,8 @@
-#!/bin/zsh
+#!/bin/sh
 if [ -d "$HOME/.rbenv" ]; then
   export PATH="$HOME/.rbenv/bin:$PATH"
 fi
+# shellcheck disable=SC2039
 if rbenv &>/dev/null; then
   eval "$(rbenv init -)"
 fi
diff --git a/ruby/rbenv.zsh b/ruby/rbenv.zsh
index 41045e06f..b7e65736d 100755
--- a/ruby/rbenv.zsh
+++ b/ruby/rbenv.zsh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 # rehash shims
 rbenv rehash 2>/dev/null
 
diff --git a/script/bootstrap b/script/bootstrap
index 11cbed2ad..24255f9bd 100755
--- a/script/bootstrap
+++ b/script/bootstrap
@@ -65,7 +65,7 @@ link_file () {
 
     if [ "$overwrite_all" == "false" ] && [ "$backup_all" == "false" ] && [ "$skip_all" == "false" ]
     then
-      # shellcheck disable=SC2086
+      # shellcheck disable=SC2086,SC2155
       local currentSrc="$(readlink $dst)"
 
       if [ "$currentSrc" == "$src" ]
diff --git a/slate/install.sh b/slate/install.sh
index 1d4e52da7..b3a86188b 100755
--- a/slate/install.sh
+++ b/slate/install.sh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" != "Darwin" ] && return 0
 brew cask install slate
diff --git a/ssh/aliases.zsh b/ssh/aliases.zsh
index dcb0bdab9..75c4ff606 100755
--- a/ssh/aliases.zsh
+++ b/ssh/aliases.zsh
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 alias pubkey="more ~/.ssh/id_rsa.pub | pbcopy | echo '=> Public key copied to pasteboard.'"
diff --git a/sublime-text-3/install.sh b/sublime-text-3/install.sh
index ff3585490..03420bd4f 100755
--- a/sublime-text-3/install.sh
+++ b/sublime-text-3/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 
 if [ "$(uname -s)" = "Darwin" ]; then
   brew cask install sublime-text3
diff --git a/system/aliases.zsh b/system/aliases.zsh
index 3f0eef526..3406b70da 100755
--- a/system/aliases.zsh
+++ b/system/aliases.zsh
@@ -1,7 +1,8 @@
-#!/bin/zsh
+#!/bin/sh
 # grc overides for ls
 #   Made possible through contributions from generous benefactors like
 #   `brew install coreutils`
+# shellcheck disable=SC2039
 if gls &>/dev/null; then
   alias ls="gls -F --color"
   alias l="gls -lAh --color"
@@ -17,17 +18,17 @@ alias grep="grep --color=auto"
 alias duf="du -sh * | sort -hr"
 alias less="less -r"
 
-if [[ -z $(command -v pbcopy) ]]; then
-  if [[ -n $(command -v xclip) ]]; then
+if [ -z "$(command -v pbcopy)" ]; then
+  if [ -n "$(command -v xclip)" ]; then
     alias pbcopy="xclip -selection clipboard"
     alias pbpaste="xclip -selection clipboard -o"
-  elif [[ -n $(command -v xsel) ]]; then
+  elif [ -n "$(command -v xsel)" ]; then
     alias pbcopy="xsel --clipboard --input"
     alias pbpaste="xsel --clipboard --output"
   fi
 fi
 
-if [[ "$(uname -s)" != "Darwin" ]]; then
+if [ "$(uname -s)" != "Darwin" ]; then
   if [ -e /usr/bin/xdg-open ]; then
     alias open="xdg-open"
   fi
diff --git a/system/env.zsh b/system/env.zsh
index bf273c051..8b6fa71ce 100755
--- a/system/env.zsh
+++ b/system/env.zsh
@@ -1,2 +1,2 @@
-#!/bin/zsh
+#!/bin/sh
 export EDITOR='atom'
diff --git a/system/grc.zsh b/system/grc.zsh
index b34959aee..67802285b 100755
--- a/system/grc.zsh
+++ b/system/grc.zsh
@@ -1,5 +1,6 @@
-#!/bin/zsh
+#!/bin/sh
 # GRC colorizes nifty unix tools all over the place
+# shellcheck disable=2039
 if grc &>/dev/null && ! brew &>/dev/null; then
-  source "$(brew --prefix)/etc/grc.bashrc"
+  . "$(brew --prefix)/etc/grc.bashrc"
 fi
diff --git a/system/path.zsh b/system/path.zsh
index cfca2006d..8600de395 100755
--- a/system/path.zsh
+++ b/system/path.zsh
@@ -1,3 +1,3 @@
-#!/bin/zsh
+#!/bin/sh
 export PATH="./bin:/usr/local/bin:/usr/local/sbin:$ZSH/bin:$PATH"
 export MANPATH="/usr/local/man:/usr/local/mysql/man:/usr/local/git/man:$MANPATH"
diff --git a/terminator/install.sh b/terminator/install.sh
index 6e0485a37..b737f388c 100755
--- a/terminator/install.sh
+++ b/terminator/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 [ "$(uname -s)" = "Darwin" ] && return 0
 mkdir -p ~/.config/terminator/
 ln -sf "$ZSH"/terminator/base16-ocean-dark.config ~/.config/terminator/config
diff --git a/vim/install.sh b/vim/install.sh
index 38acad64c..648bbaabc 100755
--- a/vim/install.sh
+++ b/vim/install.sh
@@ -1,4 +1,4 @@
-#!/bin/zsh
+#!/bin/sh
 setup_command_t() {
   cd "$ZSH"/vim/vimfiles/vim.symlink/bundle/command-t/ruby/command-t
   ruby extconf.rb
diff --git a/zsh/aliases.zsh b/zsh/aliases.zsh
index 90ca134d7..1b3a3a839 100755
--- a/zsh/aliases.zsh
+++ b/zsh/aliases.zsh
@@ -1,7 +1,7 @@
-#!/bin/zsh
+#!/bin/sh
 __reload_dotfiles() {
-  export PATH="$(command -p getconf PATH)"
-  source ~/.zshrc
+  PATH="$(command -p getconf PATH)"
+  . ~/.zshrc
   cd .
 }
 alias reload!='__reload_dotfiles'
diff --git a/zsh/completion.zsh b/zsh/completion.zsh
index 7d10a5603..6cb1aceac 100755
--- a/zsh/completion.zsh
+++ b/zsh/completion.zsh
@@ -1,8 +1,8 @@
 #!/bin/zsh
 # Force rehash when command not found
 _force_rehash() {
-    (( CURRENT == 1 )) && rehash
-    return 1
+  (( CURRENT == 1 )) && rehash
+  return 1
 }
 
 # forces zsh to realize new commands
diff --git a/zsh/window.zsh b/zsh/window.zsh
index 07d63d2ed..f5f8140ae 100755
--- a/zsh/window.zsh
+++ b/zsh/window.zsh
@@ -1,7 +1,7 @@
-#!/bin/zsh
+#!/bin/sh
 # From http://dotfiles.org/~_why/.zshrc
 # Sets the window title nicely no matter where you are
-function title() {
+title() {
   # escape '%' chars in $1, make nonprintables visible
   a=${(V)1//\%/\%\%}