Fix Vim Delete Key on macOS and Beautify the Status Bar with vim‑airline

Fix Delete/Backspace key in Vim on macOS

On macOS the Delete key (which functions as Backspace) does not delete characters in Insert mode when Vim is running in compatible mode or when the backspace option is empty. In compatible mode Vim mimics the original Vi behaviour, leaving backspace unset, which prevents deletion of indent, end‑of‑line and start‑of‑line characters.

Vim defines three possible values for the backspace option:

0   same as ":set backspace="   (Vi compatible)
1   same as ":set backspace=indent,eol"
2   same as ":set backspace=indent,eol,start"

Setting the option to 2 restores the expected Delete/Backspace behaviour. Add the following line to your ~/.vimrc (or edit the existing backspace setting):

" Enable Delete/Backspace in Insert mode
set backspace=2

Install and configure vim-airline to enhance the status line

vim-airline is a lightweight plugin that provides a configurable and attractive status line for Vim. The source repository is:

https://github.com/vim-airline/vim-airline

Installation can be performed manually by cloning the repository and copying the plugin file, or by using any Vim plugin manager.

# Manual installation
git clone https://github.com/vim-airline/vim-airline.git
cp vim-airline/plugin/airline.vim ~/.vim/plugin/
ls ~/.vim/plugin
# Expected output includes airline.vim and airline-themes.vim

After installation, add a basic configuration to ~/.vimrc. The example below sets custom separators, symbols, enables the tabline extension, selects the powerlineish theme, and includes common Vim settings that complement the airline configuration.

if !exists('g:airline_symbols')
  let g:airline_symbols = {}
endif
let g:airline_left_sep = '▶'
let g:airline_left_alt_sep = '❯'
let g:airline_right_sep = '◀'
let g:airline_right_alt_sep = '❮'
let g:airline_symbols.linenr = '¶'
let g:airline_symbols.branch = '⎇'

" Enable tabline extension
let g:airline#extensions#tabline#enabled = 1
let g:airline_theme = 'powerlineish'

" General Vim options
set laststatus=2          " Always show status line
set encoding=utf-8
set t_Co=256
set fillchars+=stl:\ ,stlnc:\
set term=xterm-256color
set termencoding=utf-8
set nocompatible          " Disable Vi‑compatible mode
set number                " Show line numbers
syntax enable
set backspace=2           " Ensure Delete works as expected

Additional themes are available in the separate repository:

https://github.com/vim-airline/vim-airline-themes

To use a theme, clone the repository and place the theme files in ~/.vim/airline/themes/, then set let g:airline_theme = 'theme_name' in .vimrc.