diff --git a/share/completions/brew.fish b/share/completions/brew.fish
new file mode 100644
index 000000000..003b2ecad
--- /dev/null
+++ b/share/completions/brew.fish
@@ -0,0 +1,202 @@
+function __fish_brew_needs_command
+  set cmd (commandline -opc)
+  if [ (count $cmd) -eq 1 -a $cmd[1] = 'brew' ]
+    return 0
+  end
+  return 1
+end
+
+function __fish_brew_using_command
+  set cmd (commandline -opc)
+  if [ (count $cmd) -gt 1 ]
+    if [ $argv[1] = $cmd[2] ]
+      return 0
+    end
+  end
+  return 1
+end
+
+function __fish_brew_formulae
+    set -l formuladir (brew --repository)/Library/Formula/
+    # __fish_complete_suffix .rb
+    ls $formuladir/*.rb | sed 's/.rb$//' | sed "s|^$formuladir||"
+end
+
+############
+# commands #
+############
+
+# audit
+complete -f -c brew -n '__fish_brew_needs_command' -a audit -d 'Check formula'
+complete -f -c brew -n '__fish_brew_using_command audit' -a '(__fish_brew_formulae)' -d 'formula'
+
+# cat
+complete -f -c brew -n '__fish_brew_needs_command' -a cat -d 'Display formula'
+complete -f -c brew -n '__fish_brew_using_command cat' -a '(__fish_brew_formulae)' -d 'formula'
+
+# cleanup
+complete -f -c brew -n '__fish_brew_needs_command' -a cleanup -d 'Remove old installed versions'
+complete -f -c brew -n '__fish_brew_using_command cleanup' -l force -d 'Remove out-of-date keg-only brews as well'
+complete -f -c brew -n '__fish_brew_using_command cleanup' -a '-n' -d 'Dry run'
+complete -f -c brew -n '__fish_brew_using_command cleanup' -a '-s' -d 'Scrubs the cache'
+complete -f -c brew -n '__fish_brew_using_command cleanup' -a '(__fish_brew_formulae)' -d 'formula'
+
+# create
+complete -f -c brew -n '__fish_brew_needs_command' -a create -d 'Create new formula from URL'
+complete -f -c brew -n '__fish_brew_using_command create' -a '--cmake' -d 'Use template for CMake-style build'
+complete -f -c brew -n '__fish_brew_using_command create' -a '--autotools' -d 'Use template for Autotools-style build'
+complete -f -c brew -n '__fish_brew_using_command create' -a '--no-fetch' -d 'Don\'t download URL'
+
+# deps
+complete -f -c brew -n '__fish_brew_needs_command' -a deps -d 'Show a formula\'s dependencies'
+complete -f -c brew -n '__fish_brew_using_command deps' -a '--1' -d 'Show only 1 level down'
+complete -f -c brew -n '__fish_brew_using_command deps' -a '-n' -d 'Show in topological order'
+complete -f -c brew -n '__fish_brew_using_command deps' -a '--tree' -d 'Show dependencies as tree'
+complete -f -c brew -n '__fish_brew_using_command deps' -a '--all' -d 'Show dependencies for all formulae'
+complete -f -c brew -n '__fish_brew_using_command deps' -a '(__fish_brew_formulae)' -d 'formula'
+
+# diy
+complete -f -c brew -n '__fish_brew_needs_command' -a 'diy configure' -d 'Determine installation prefix for non-brew software'
+complete -f -c brew -n '__fish_brew_using_command diy' -a '--set-name' -d 'Set name of package'
+complete -f -c brew -n '__fish_brew_using_command diy' -a '--set-version' -d 'Set version of package'
+
+complete -f -c brew -n '__fish_brew_needs_command' -a 'doctor' -d 'Check your system for problems'
+complete -f -c brew -n '__fish_brew_needs_command' -a 'edit' -d 'Open brew/formula for editing'
+
+# fetch
+complete -f -c brew -n '__fish_brew_needs_command' -a fetch -d 'Download source for formula'
+complete -f -c brew -n '__fish_brew_using_command fetch' -a '--force' -d 'Remove a previously cached version and re-fetch'
+complete -f -c brew -n '__fish_brew_using_command fetch' -a '--HEAD' -d 'Download the HEAD version from a VCS'
+complete -f -c brew -n '__fish_brew_using_command fetch' -a '--deps' -d 'Also download dependencies'
+complete -f -c brew -n '__fish_brew_using_command fetch' -a '-v' -d 'Make HEAD checkout verbose'
+complete -f -c brew -n '__fish_brew_using_command fetch' -a '(__fish_brew_formulae)' -d 'formula'
+
+complete -f -c brew -n '__fish_brew_needs_command' -a 'help' -d 'Display help'
+
+# home
+complete -f -c brew -n '__fish_brew_needs_command' -a home -d 'Open brew/formula\'s homepage'
+complete -c brew -n '__fish_brew_using_command home' -a '(__fish_brew_formulae)' -d 'formula'
+
+# info
+complete -f -c brew -n '__fish_brew_needs_command' -a 'info abv' -d 'Display information about formula'
+complete -f -c brew -n '__fish_brew_using_command info' -a '--all' -d 'Display info for all formulae'
+complete -f -c brew -n '__fish_brew_using_command info' -a '--github' -d 'Open the GitHub History page for formula'
+complete -c brew -n '__fish_brew_using_command info' -a '(__fish_brew_formulae)' -d 'formula'
+
+# install
+complete -f -c brew -n '__fish_brew_needs_command' -a 'install' -d 'Install formula'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--force' -d 'Force install'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--debug' -d 'If install fails, open shell in temp directory'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--ignore-dependencies' -d 'skip installing any dependencies of any kind'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--fresh' -d 'Don\'t re-use any options from previous installs'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--use-clang' -d 'Attempt to compile using clang'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--use-gcc' -d 'Attempt to compile using GCC'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--use-llvm' -d 'Attempt to compile using the LLVM'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--build-from-source' -d 'Compile from source even if a bottle is provided'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--devel' -d 'Install the development version of formula'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--HEAD' -d 'Install the HEAD version from VCS'
+complete -f -c brew -n '__fish_brew_using_command install' -a '--interactive' -d 'Download and patch formula, then open a shell'
+complete -c brew -n '__fish_brew_using_command install' -a '(__fish_brew_formulae)' -d 'formula'
+
+# link
+complete -f -c brew -n '__fish_brew_needs_command' -a 'link ln' -d 'Symlink installed formula'
+complete -f -c brew -n '__fish_brew_using_command link' -a '(__fish_brew_formulae)' -d 'formula'
+complete -f -c brew -n '__fish_brew_using_command ln' -a '(__fish_brew_formulae)' -d 'formula'
+
+# list
+complete -f -c brew -n '__fish_brew_needs_command' -a 'list ls' -d 'List all installed formula'
+complete -f -c brew -n '__fish_brew_using_command list' -a '--unbrewed' -d 'List all files in the Homebrew prefix not installed by brew'
+complete -f -c brew -n '__fish_brew_using_command list' -a '--versions' -d 'Show the version number'
+complete -c brew -n '__fish_brew_using_command list' -a '(__fish_brew_formulae)' -d 'formula'
+#ls
+complete -f -c brew -n '__fish_brew_using_command ls' -a '--unbrewed' -d 'List all files in the Homebrew prefix not installed by brew'
+complete -f -c brew -n '__fish_brew_using_command ls' -a '--versions' -d 'Show the version number'
+complete -c brew -n '__fish_brew_using_command ls' -a '(__fish_brew_formulae)' -d 'formula'
+
+# log
+complete -f -c brew -n '__fish_brew_needs_command' -a log -d 'Show log for formula'
+complete -c brew -n '__fish_brew_using_command log' -a '(__fish_brew_formulae)' -d 'formula'
+
+# missing
+complete -f -c brew -n '__fish_brew_needs_command' -a missing -d 'Check formula for missing dependencies'
+complete -c brew -n '__fish_brew_using_command missing' -a '(__fish_brew_formulae)' -d 'formula'
+
+# options
+complete -f -c brew -n '__fish_brew_needs_command' -a options -d 'Display install options for formula'
+complete -c brew -n '__fish_brew_using_command options' -a '(__fish_brew_formulae)' -d 'formula'
+
+# outdated
+complete -f -c brew -n '__fish_brew_needs_command' -a outdated -d 'Show formula that have updated versions'
+complete -f -c brew -n '__fish_brew_using_command outdated' -a '--quiet' -d 'Display only names'
+
+# prune
+complete -f -c brew -n '__fish_brew_needs_command' -a prune -d 'Remove dead symlinks'
+
+# search
+complete -f -c brew -n '__fish_brew_needs_command' -a 'search -S' -d 'Search for formula by name'
+complete -f -c brew -n '__fish_brew_using_command search' -a '--macports' -d 'Search on MacPorts'
+complete -f -c brew -n '__fish_brew_using_command search' -a '--fink' -d 'Search on Fink'
+complete -f -c brew -n '__fish_brew_using_command -S' -a '--macports' -d 'Search on MacPorts'
+complete -f -c brew -n '__fish_brew_using_command -S' -a '--fink' -d 'Search on Fink'
+
+# tap
+complete -f -c brew -n '__fish_brew_needs_command' -a tap -d 'Tap a new formula repository on GitHub'
+
+# test
+complete -f -c brew -n '__fish_brew_needs_command' -a test -d 'Run tests for formula'
+complete -c brew -n '__fish_brew_using_command test' -a '(__fish_brew_formulae)' -d 'formula'
+
+# uninstall
+complete -f -c brew -n '__fish_brew_needs_command' -a 'uninstall remove rm' -d 'Uninstall formula'
+complete -c brew -n '__fish_brew_using_command uninstall' -a '(__fish_brew_formulae)' -d 'formula'
+complete -c brew -n '__fish_brew_using_command remove' -a '(__fish_brew_formulae)' -d 'formula'
+complete -c brew -n '__fish_brew_using_command rm' -a '(__fish_brew_formulae)' -d 'formula'
+complete -f -c brew -n '__fish_brew_using_command uninstall' -a '--force' -d 'Delete all installed versions'
+complete -f -c brew -n '__fish_brew_using_command remove' -a '--force' -d 'Delete all installed versions'
+complete -f -c brew -n '__fish_brew_using_command rm' -a '--force' -d 'Delete all installed versions'
+
+# unlink
+complete -f -c brew -n '__fish_brew_needs_command' -a unlink -d 'Unlink formula'
+complete -c brew -n '__fish_brew_using_command unlink' -a '(__fish_brew_formulae)' -d 'formula'
+
+# untap
+complete -f -c brew -n '__fish_brew_needs_command' -a untap -d 'Remove a tapped repository'
+
+# update
+complete -f -c brew -n '__fish_brew_needs_command' -a update -d 'Fetch newest version of Homebrew and formulas'
+complete -f -c brew -n '__fish_brew_using_command update' -a '--rebase' -d 'Use git pull --rebase'
+
+# upgrade
+complete -f -c brew -n '__fish_brew_needs_command' -a upgrade -d 'Upgrade outdated brews'
+complete -c brew -n '__fish_brew_using_command upgrade' -a '(__fish_brew_formulae)' -d 'formula'
+
+# uses
+complete -f -c brew -n '__fish_brew_needs_command' -a uses -d 'Show formulas that depend on specified formula'
+complete -f -c brew -n '__fish_brew_using_command uses' -a '--installed' -d 'List only installed formulae'
+complete -c brew -n '__fish_brew_using_command uses' -a '(__fish_brew_formulae)' -d 'formula'
+
+# versions
+complete -f -c brew -n '__fish_brew_needs_command' -a versions -d 'List previous versions of formula'
+complete -f -c brew -n '__fish_brew_using_command versions' -a '--compact' -d 'Show all options on a single line'
+complete -c brew -n '__fish_brew_using_command versions' -a '(__fish_brew_formulae)' -d 'formula'
+
+
+############
+# switches #
+############
+complete -f -c brew -n '__fish_brew_needs_command' -a '-v --version' -d 'Print version number of brew'
+complete -f -c brew -n '__fish_brew_needs_command' -l repository -x -d 'Display where Homebrew\'s .git directory is located'
+complete -f -c brew -n '__fish_brew_needs_command' -l config -x -d 'Show Homebrew and system configuration'
+
+# --prefix
+complete -f -c brew -n '__fish_brew_needs_command' -l prefix -d 'Display Homebrew\'s install path'
+complete -f -c brew -n '__fish_brew_using_command --prefix' -a '(__fish_brew_formulae)' -d 'Display formula\'s install path'
+
+# --cache
+complete -f -c brew -n '__fish_brew_needs_command' -l cache -d 'Display Homebrew\'s download cache'
+complete -f -c brew -n '__fish_brew_needs_command' -n '__fish_brew_using_command --cache' -a '(__fish_brew_formulae)' -d 'Display the file or directory used to cache formula'
+
+# --cellar
+complete -f -c brew -n '__fish_brew_needs_command' -l cellar -d 'Display Homebrew\'s Cellar path'
+complete -f -c brew -n '__fish_brew_using_command --cellar' -a '(__fish_brew_formulae)' -d 'Display formula\'s install path in Cellar'
+