Alacritty - Fast Terminal That Uses Your Graphics Card

Joe Wilm got frustrated with how slow his terminal was when running Vim inside tmux back in 2017. Instead of complaining on Twitter like the rest of us, he built a terminal emulator in Rust that uses your graphics card to render text with OpenGL.

The Problem: Every Terminal Is Slow

Your terminal stutters when you scroll through logs. It freezes when you cat a 50MB file. iTerm2 uses 200MB of RAM for some reason. GNOME Terminal can't handle high-speed output without dropping frames. Windows Terminal is better but still chokes on large files.

This happens because traditional terminals use your CPU to draw every character. When you're dumping thousands of lines, your CPU becomes the bottleneck. Alacritty fixes this by using OpenGL to offload text rendering to your GPU - the same chip that handles video games and 3D graphics. The GPU acceleration approach fundamentally changes how text gets rendered.

What You Give Up for Speed

Alacritty is fast because it doesn't do anything else. No tabs - use tmux or open multiple windows. No GUI preferences - edit a TOML file by hand. No clickable URLs out of the box - learn vi-mode or copy-paste like an animal. No split panes either - that's what window managers are for.

If you're coming from iTerm2, you'll miss all the convenience features for a while. But when you spend hours in terminal daily, the speed difference makes the learning curve worthwhile. Check the feature comparison to see what's missing.

Real-World Performance

Scrolling through Docker logs is smooth on my MacBook instead of the usual stuttering. Kubernetes log streaming doesn't drop frames. Running pytest with verbose output actually shows every line. Even tail -f on massive log files stays responsive.

The vtebench results show Alacritty handling way more text output than iTerm2. Real benefit is consistency - performance doesn't tank when you have Chrome tabs eating your RAM. Independent benchmarks confirm the speed advantage.

Current State: Beta That Works in Production

It's September 2025 and this is still labeled "beta" despite being more stable than iTerm2. Version 0.15.1 (released February 2025) is current stable, with 0.16.0-rc1 from August in testing. Has 60.2k GitHub stars and gets used daily by developers who prioritize speed. The issue tracker is active with maintainers responding regularly. I learned this the hard way: breaking changes happen between versions, so backup your config files before updating.

Available through package managers: brew install alacritty on macOS, sudo apt install alacritty on Ubuntu, or download binaries for Windows. The Arch package stays current because that's how Arch works. Also available on NixOS and Gentoo.

Installing Alacritty is straightforward. Getting it configured properly takes work.

Package Manager Installation (The Easy Stuff)

macOS: brew install alacritty then realize it won't show up in Spotlight because the .app bundle doesn't get indexed properly. Launch from terminal with alacritty or find it in /Applications/Alacritty.app. This shit bit me when I first installed it - spent 10 minutes wondering where it went. You can fix the Spotlight indexing issue manually.

Ubuntu/Debian: The PPA sometimes lags behind releases. Either wait or compile from source:

sudo add-apt-repository ppa:aslatter/ppa
sudo apt install alacritty

You'll need Rust installed for source compilation. Check the official installation guide for dependencies.

Arch Linux: sudo pacman -S alacritty because Arch packages are always current. Available in the community repository.

Fedora: sudo dnf install alacritty should work. If not, enable the COPR repo. Check Fedora's package database for current versions.

Windows: Download from GitHub releases or scoop install alacritty. The Windows version works but you'll miss some Unix-specific features. Scoop is the easiest install method. Also available via winget.

GPU Requirements (Usually Not a Problem)

Needs OpenGL ES 2.0 which every computer from 2010+ has. Works fine on integrated graphics. If you have ancient Intel HD 3000 or similar garbage, you might see rendering issues.

On Linux, make sure your graphics drivers are installed. Mesa works for AMD/Intel, NVIDIA proprietary drivers for NVIDIA cards. Check GPU compatibility if you're having issues. The OpenGL requirements are well-documented.

Configuration File Setup (The Painful Part)

Alacritty doesn't create a config file. You create one manually at:

• Linux/macOS: ~/.config/alacritty/alacritty.toml
• Windows: %APPDATA%\alacritty\alacritty.toml

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

Basic Config That Doesn't Suck

The defaults look terrible. Here's a minimal config:

[font]
normal = { family = \"FiraCode Nerd Font\", style = \"Regular\" }
size = 12.0

[window]
opacity = 0.95
padding = { x = 10, y = 10 }

[colors]
## Use a theme or your terminal will hurt your eyes

Font Hell (Install a Nerd Font)

The default font looks like 1995. Install a Nerd Font for icons. Powerline symbols also work but Nerd Fonts have thousands more glyphs.

• macOS: brew install font-fira-code-nerd-font or check Homebrew fonts
• Linux: Download from releases or use your package manager
• Windows: Download and install manually or use Scoop fonts

Font rendering can look blurry on some systems. Tweak the font size until it's crisp. Check the font troubleshooting guide for platform-specific issues. FontForge can help debug font problems.

Theme Setup (Or Suffer Ugly Colors)

Clone the themes repo:

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

Add to your config:

import = [\"~/.config/alacritty/themes/themes/dracula.toml\"]

Common Gotchas

Config file errors fail silently. Invalid TOML syntax = Alacritty uses defaults with zero error message. I spent 3 hours debugging why my font wasn't loading - turned out I had a missing quote in the TOML. Check alacritty --print-events to debug config issues. Use a TOML validator when things go wrong.

Font names are picky as hell. \"Fira Code\" won't work, \"FiraCode Nerd Font\" might work, \"FiraCode Nerd Font Mono\" probably works. Run fc-list on Linux or use Font Book on macOS to get exact font names. This drove me insane for a weekend. Check the font configuration docs for examples.

Color schemes break between versions. The TOML format changed in 0.13.0 and broke everyone's configs. Pin your config in git and test release candidates before updating production. Use semantic versioning to track breaking changes.

No tabs means learning tmux. Budget 2-3 hours to get comfortable with tmux basics. After 6 months of tmux, going back to terminal tabs feels primitive. Check tmux cheat sheet for key bindings. Zellij is a modern alternative.

Video Tutorial Worth Watching

Josean Martinez has a solid YouTube tutorial on Alacritty setup. Unlike most tutorials that skip the annoying parts, he shows the real gotchas: silent config failures, font rendering issues, and vi-mode URL handling. His written guide covers the same setup with copy-paste configs.

Real issues you'll hit after switching and how to fix them without losing your shit.

GPU Drivers Breaking Everything

NVIDIA on Linux: If you see thread 'main' panicked at 'Failed to create OpenGL context', your NVIDIA drivers are fucked. Fixed it with:

sudo apt install nvidia-driver-535 nvidia-utils-535
## Reboot required (yes, on Linux)

Check the NVIDIA install guide and graphics troubleshooting.

Intel HD Graphics on old machines: Works fine until you try transparency. Remove opacity = 0.95 from your config if you get weird rendering artifacts. The Intel graphics driver support varies by chipset. Check compatibility issues.

macOS with external monitors: Font rendering looks like garbage on non-Retina displays. Add this to your config:

[font]
builtin_box_drawing = false

This is a known macOS font rendering issue with external displays. The macOS font smoothing settings also affect rendering.

Config File Hell

Silent failures everywhere. No error messages when your TOML is broken. I spent 4 hours debugging a missing comma. This is the biggest pain point in Alacritty's config system.

Copy this debug command: alacritty --print-events shows config parsing in real-time. Also try online TOML validators before going insane.

Font detection is unreliable. Even if Font Book shows "FiraCode Nerd Font", Alacritty might need "FiraCode Nerd Font Mono". Test fonts one by one:

## Check what fonts are actually available
fc-list | grep -i fira
## On macOS
system_profiler SPFontsDataType | grep -i fira

Check the font configuration documentation and font troubleshooting issues.

Import paths break between updates. Relative imports like import = ["./themes/dracula.toml"] stop working when Alacritty changes its working directory behavior. Use absolute paths: ~/.config/alacritty/themes/dracula.toml. This changed in version 0.12 and broke many configs.

Terminal Emulation Bugs

Tmux mouse mode breaks. Clicking doesn't work in tmux panes. Fixed with this in your ~/.tmux.conf:

set -g terminal-overrides ',alacritty:RGB'
set -g mouse on

This is a known tmux integration issue. Check the tmux configuration guide for more terminal compatibility settings.

Vi-mode URL selection is finicky. URLs with underscores or dashes at the end get cut off. The regex is too strict. No fix, just copy manually or use a different hint mode. This is tracked in GitHub.

Shell integration breaks on updates. If your prompt looks fucked after an Alacritty update, check if your shell config assumes specific terminfo capabilities. Reset with export TERM=alacritty. Check shell compatibility for your shell.

Performance Issues Nobody Talks About

Memory usage creeps up over time. After running for days, Alacritty can hit 200MB+ with just scrollback. Restart occasionally or reduce scrollback history:

[scrolling]
history = 5000  # Default is 10000

This is a known memory issue with large scrollback buffers. Monitor with htop or Activity Monitor.

GPU memory leaks on Windows. Some Windows GPU drivers leak VRAM. Monitor with Task Manager GPU tab. Only fix is restarting Alacritty. This affects older NVIDIA drivers more than recent ones.

Slow startup on network filesystems. If your config is on NFS/SMB, Alacritty hangs on startup. Copy config locally or use --config-file to specify a local path. This is a file system performance issue.

The Nuclear Option

When everything's fucked and you just need it to work:

## Remove all config, start fresh
mv ~/.config/alacritty ~/.config/alacritty.broken
mkdir ~/.config/alacritty
## Minimal working config
cat > ~/.config/alacritty/alacritty.toml << EOF
[font]
normal = { family = "monospace" }
size = 12.0
EOF

Most issues are config-related. Start minimal, add features one by one, commit working configs to git. Check the troubleshooting guide and configuration examples for reference. The community wiki has additional troubleshooting tips.