The Asynchronous Lint Engine (ALE) vim-ale plugin for Vim 8+ and NeoVim provides linting of many syntaxes during editing, before files are saved. Supported JavaScript linters include eslint, jscs, jshint, flow, standard, and xo. Installation instructions can be found at https://github.com/w0rp/ale#3-installation.

Here is suggested ALE configuration to place in your .vimrc file:

" Asynchronous Lint Engine (ALE)
" Limit linters used for JavaScript.
let g:ale_linters = {
\  'javascript': ['flow'] " can add more
highlight clear ALEErrorSign " otherwise uses error bg color (typically red)
highlight clear ALEWarningSign " otherwise uses error bg color (typically red)
let g:ale_sign_error = 'X' " could use emoji
let g:ale_sign_warning = '?' " could use emoji
let g:ale_statusline_format = ['X %d', '? %d', '']
" %linter% is the name of the linter that provided the message
" %s is the error or warning message
let g:ale_echo_msg_format = '%linter% says %s'
" Map keys to navigate between lines with errors and warnings.
nnoremap <leader>an :ALENextWrap<cr>
nnoremap <leader>ap :ALEPreviousWrap<cr>


Another way to add support for Flow in Vim is to use vim-flow.

  • Adds completions to omnifunc
  • Checks JavaScript files for type errors on save


  • Requires Flow to be installed and available on your path.
  • Requires projects containing JavaScript files to be initialised with flow init.
  • Requires JavaScript files to be marked with /* @flow */ at the top.


cd ~/.vim/bundle
git clone git://github.com/flowtype/vim-flow.git


Add this to your ~/.vimrc

NeoBundleLazy 'flowtype/vim-flow', {
    \ 'autoload': {
    \     'filetypes': 'javascript'
    \ }}

With Flow build step, using flow-bin

NeoBundleLazy 'flowtype/vim-flow', {
    \ 'autoload': {
    \     'filetypes': 'javascript'
    \ },
    \ 'build': {
    \     'mac': 'npm install -g flow-bin',
    \     'unix': 'npm install -g flow-bin'
    \ }}

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