simple vimrc (for vim 7+)

vimrc

" Plugins.
call plug#begin()
Plug 'luiarthur/tmux.vim'
Plug 'luiarthur/red.vim'
call plug#end()

" Color scheme.
silent! colorscheme noir  " depends on `luiarthur/red.vim`

" Tab / buffer navigation.
map <S-Right> :tabnext<CR>
map <S-Left> :tabprevious<CR>
map <S-Down> :bnext<CR>
map <S-Up> :bprevious<CR>

" Basic stuff
set number                  " Show line numbers on side.
syntax enable               " Syntax highlighting
set hlsearch                " Highlight search items
set incsearch               " Highlight search items as you type
set showmatch               " Show matches for parenthesis, etc.
set expandtab               " Use softtabs
set tabstop=2 shiftwidth=2  " Set tab width
set autoindent              " Automaticall indent lines
set nobackup                " Don't create .swp
set clipboard=unnamedplus   " copy and paste to clipboard.
set guicursor=a:blinkon0    " disable cursor blinking
set laststatus=0 ruler      " Hides status bar. The airline plugin seems to ignore this.
set splitbelow              " vertical splits create windows below by default.
set splitright              " horizontal splits create window to the right by default.
set mouse=a                 " enable copy / paste using mouse, while in vim.
set fillchars=stl:-         " fill active window's statusline with -
set fillchars+=stlnc:-      " also fill inactive windows' statusline with -

" Indenting / unindenting in visual mode
vmap < <gv  
vmap > >gv
vmap <s-tab> <gv
vmap <tab> >gv

" disable F1 for help
nmap <F1> <nop>

" Reset syntax highlight
noremap <F10> <ESC>:syntax sync fromstart<CR>
inoremap <F10> <C-o>:syntax sync fromstart<CR>

" Return to last position
augroup return_cursor_to_last_position
    autocmd!
    autocmd BufReadPost * if line("'\"") > 1 && line("'\"") <= line("$") | exe "normal! g`\"" | endif
augroup END

" Always open new files as tabs.
" NOTE: tabs can be close with `:bd`.
augroup open-tabs
    au!
    au VimEnter * ++nested if !&diff | tab all | tabfirst | endif
augroup end

" Spell check for markdown files.
au BufRead *.md setlocal spell

" Highlight column 80
" function! MarkCol80()
"   highlight ColorColumn ctermbg=red
"   call matchadd('ColorColumn', '\%81v', 100)
" endfunction
" au BufRead *.{py,jl,R,scala,md} call MarkCol80()

" Copy and paste between vim sessions.
" Copy the current visual selection to ~/.vbuf.
" For servers, uncomment the following lines:
vmap <C-S-y> :w! ~/.vbuf<CR>     " copy the current visual selection to ~/.vbuf
nmap <C-S-p> :r ~/.vbuf<CR>      " paste the contents of the buffer file

Alternatively, we can avoid using plug.vim by putting tmux.vim in ~/.vim/plugin/, and putting red.vim and noir.vim in ~/.vim/colors/.