How to make Vim detect filetype from the shebang line?
Following the instructions listed in :help new-filetype-scripts,create the scripts.vim file in the user runtime directory (~/.vim/on Unix-like systems), and write the following script in it:
if did_filetype() finishendifif getline(1) =~# '^#!.*/bin/env\s\+node\>' setfiletype javascriptendif
If you're interested in a plugin, one does exist for this:
https://github.com/vitalk/vim-shebang
This contains a pattern for node -> javascript highlighting.
AddShebangPattern! javascript ^#!.*\s\+node\>