Alacritty is a fast, GPU-accelerated terminal emulator written in Rust. It is deliberately simple, so this guide covers the few things worth configuring.

Alacritty adheres to the so called suckless program philosophy. It has no GUI settings editor or built-in pane manager. On macOS it can use native tabs, but for portable tabs, panes, and persistent sessions you still need a terminal multiplexer such as tmux.

That either sucks less or sucks more, depending on your personality.

Install Alacritty on macOS

Download the latest macOS .dmg from the Alacritty releases page, open it, and drag Alacritty into Applications.

The app is not notarized. If macOS blocks the first launch, open System Settings → Privacy & Security and choose Open Anyway. Only do this when you downloaded Alacritty from its official GitHub repository.

Check the installed version:

$ /Applications/Alacritty.app/Contents/MacOS/alacritty --version
alacritty 0.17.0

This article targets Alacritty 0.17.0. Check the release notes when using a newer version.

Set up terminfo

Terminfo describes the terminal's capabilities to programs such as tmux and Vim. First check whether the Alacritty entry is already installed:

$ infocmp alacritty

If that command prints an error, install the entry for your user:

$ git clone --depth 1 --branch v0.17.0 \
    https://github.com/alacritty/alacritty.git
$ cd alacritty
$ tic -o ~/.terminfo -xe alacritty,alacritty-direct extra/alacritty.info

Run infocmp alacritty again to verify it. You may also need the entry on a remote host when connecting over SSH.

Configure Alacritty

Alacritty uses TOML and does not create a config file for you. Create ~/.config/alacritty/alacritty.toml:

$ mkdir -p ~/.config/alacritty
$ touch ~/.config/alacritty/alacritty.toml

Open the file in your editor. This makes the config easy to keep in your dotfiles and share between machines. See the official config reference for every option.

Copy selected text

Copy selected text to the system clipboard without pressing Cmd+C:

[selection]
save_to_clipboard = true

Use Option as Alt

On macOS, the Option key types characters such as # and € by default. To send Option as Alt to terminal programs instead, choose which Option key to remap:

[window]
option_as_alt = "OnlyLeft"

The valid values are "OnlyLeft", "OnlyRight", "Both", and "None". Keeping one Option key unmodified lets you type macOS special characters.

Use fish

Alacritty uses $SHELL by default and starts a login shell on macOS. If fish is already your login shell, no Alacritty setting is needed.

To force a particular shell, find its path with command -v fish, then add it to the config:

[terminal]
shell = { program = "/opt/homebrew/bin/fish", args = ["--login"] }

Use the path printed on your machine. Intel Macs commonly use /usr/local/bin/fish instead.

Open URLs

Alacritty detects URLs and opens them with the macOS open command by default. Click a highlighted URL, or press Ctrl+Shift+O and then its hint key.

If an application such as tmux has captured the mouse, hold Shift while clicking to bypass mouse reporting.

Add a color theme

The Alacritty theme repository contains ready-made TOML themes. Clone it:

$ git clone https://github.com/alacritty/alacritty-theme \
    ~/.config/alacritty/themes

Then import a theme near the top of alacritty.toml:

[general]
import = ["~/.config/alacritty/themes/themes/catppuccin_mocha.toml"]

Example config

Here is a complete, small config based on my original setup:

[window]
padding = { x = 10, y = 10 }
opacity = 0.99
 
[scrolling]
history = 100000
multiplier = 3
 
[font]
size = 16.0
 
[font.normal]
family = "Menlo"
style = "Regular"
 
[colors]
draw_bold_text_with_bright_colors = true
 
[colors.primary]
background = "#181818"
foreground = "#d8d8d8"
 
[colors.cursor]
text = "#181818"
cursor = "#d8d8d8"
 
[colors.normal]
black = "#181818"
red = "#ab4642"
green = "#a1b56c"
yellow = "#f7ca88"
blue = "#7cafc2"
magenta = "#ba8baf"
cyan = "#86c1b9"
white = "#d8d8d8"
 
[colors.bright]
black = "#585858"
red = "#ab4642"
green = "#a1b56c"
yellow = "#f7ca88"
blue = "#7cafc2"
magenta = "#ba8baf"
cyan = "#86c1b9"
white = "#f8f8f8"
 
[bell]
animation = "EaseOutExpo"
duration = 300
color = "#ffffff"
 
[selection]
save_to_clipboard = true
 
[cursor]
style = { shape = "Block", blinking = "Off" }
unfocused_hollow = true

Alacritty reloads config changes automatically. Errors appear in the terminal window; you can also run Alacritty with -vv for more detail.

Keyboard shortcuts

These are the most useful default shortcuts on macOS:

See the default bindings reference for the full list.

Custom bindings belong in the [keyboard] table. For example, this creates a new window with Cmd+Shift+N:

[keyboard]
bindings = [
  { key = "N", mods = "Command|Shift", action = "CreateNewWindow" },
]

Vi mode

Vi mode lets you navigate the terminal's scrollback with familiar Vim keys. It does not edit the current shell command.

Press Ctrl+Shift+Space to enter or leave Vi mode. Move with

h, j, k, and l. Press v to start a selection and y to copy it. Press / to search, or Enter to open the URL under the cursor.

Start Alacritty from the command line

Open a new macOS instance:

$ open -na Alacritty

To start Alacritty with a different config file, call the executable inside the app bundle:

$ /Applications/Alacritty.app/Contents/MacOS/alacritty \
    --config-file ~/.config/alacritty/party-mode.toml

View all command-line options:

$ /Applications/Alacritty.app/Contents/MacOS/alacritty --help

Add tmux

Alacritty does not provide portable panes or persistent sessions, so tmux is a useful companion.

Install and start tmux:

$ brew install tmux
$ tmux

Tmux shortcuts start with Ctrl+B, followed by another key. For example, Ctrl+B % splits the current window into left and right panes. Ctrl+B c creates a window, Ctrl+B n selects the next window, and Ctrl+B p selects the previous one.

Conclusion

Alacritty stays out of the way: configure the window, font, colors, and keys in one TOML file, then let your shell and tmux handle the rest.