ghostty is a cross-platform, GPU-accelerated terminal emulator that aims to push the boundaries of what is possible with a terminal emulator by exposing modern, opt-in features that enable CLI tool developers to build more feature rich, interactive applications.

There are a number of excellent terminal emulator options that exist today. The unique goal of ghostty is to have a platform for experimenting with modern, optional, non-standards-compliant features to enhance the capabilities of CLI applications. We aim to be the best in this category, and competitive in the rest.

While aiming for this ambitious goal, ghostty is a fully standards compliant terminal emulator that aims to remain compatible with all existing shells and software. You can use this as a drop-in replacement for your existing terminal emulator.

Project Status: Beta. Ghostty implements most of the baseline features you'd expect for a terminal you can work in every day. We're still missing things, but I've been using it full time since April 2022.

Download

Platform / Package	Links	Notes
macOS	Tip ("Nightly")	MacOS 12+ Universal Binary
Linux (Flatpak)	Tip ("Nightly")
Linux (Other)	Build from Source
Windows	n/a	Not supported yet

Configuration

To configure Ghostty, you must use a configuration file. GUI-based configuration is on the roadmap but not yet supported. The configuration file must be placed at $XDG_CONFIG_HOME/ghostty/config, which defaults to ~/.config/ghostty/config if the XDG environment is not set.

The file format is documented below as an example:

# The syntax is "key = value". The whitespace around the equals doesn't matter.
background = 282c34
foreground= ffffff

# Blank lines are ignored!

keybind = ctrl+z=close_surface
keybind = ctrl+d=new_split:right

# Colors can be changed by setting the 16 colors of `palette`, which each color
# being defined as regular and bold.
#
# black
palette = 0=#1d2021
palette = 8=#7c6f64
# red
palette = 1=#cc241d
palette = 9=#fb4934
# green
palette = 2=#98971a
palette = 10=#b8bb26
# yellow
palette = 3=#d79921
palette = 11=#fabd2f
# blue
palette = 4=#458588
palette = 12=#83a598
# purple
palette = 5=#b16286
palette = 13=#d3869b
# aqua
palette = 6=#689d6a
palette = 14=#8ec07c
# white
palette = 7=#a89984
palette = 15=#fbf1c7

The available keys and valid values are not easily documented yet, but they are easily visible if you're mildly comfortable with Zig. The available keys are just the keys (verbatim) in the Config structure. The keys are documented there, too.

Debugging Configuration

You can verify that configuration is being properly loaded by looking at the debug output of Ghostty. Documentation for how to view the debug output is in the "building Ghostty" section at the end of the README.

In the debug output, you should see in the first 20 lines or so messages about loading (or not loading) a configuration file, as well as any errors it may have encountered. Ghostty currently ignores errors and treats it as if the configuration had not been set, so this is the best place to look if something isn't working.

Eventually, we'll have a better mechanism for showing errors to the user.

Shell Integration

Ghostty supports some features that require shell integration. I am aiming to support many of the features that Kitty supports for shell integration.

The currently support shell integration features in Ghostty:

We do not confirm close for windows where the cursor is at a prompt.
New terminals start in the working directory of the previously focused terminal.
The cursor at the prompt is turned into a bar.
The scroll_to_prompt keybinding can be used to scroll the terminal window forward and back through prompts.

Shell Integration Installation and Verification

Ghostty will automatically inject the shell integration code for zsh and fish. bash does not support automatic injection but you can manually source the ghostty.bash file in src/shell-integration. Other shells are not supported. If you want to disable this feature, set shell-integration = none in your configuration file.

For the automatic shell integration to work, Ghostty must either be run from the macOS app bundle or be installed in a location where the contents of zig-out/share are available somewhere above the directory where Ghostty is running from. On Linux, this should automatically work if you run from the zig-out directory tree structure (a standard FHS-style tree).

You may also manually set the GHOSTTY_RESOURCES_DIR to point to the zig-out/share contents. To validate this directory the file $GHOSTTY_RESOURCES_DIR/terminfo/ghostty.terminfo should exist.

To verify shell integration is working, look for the following log lines:

info(io_exec): using Ghostty resources dir from env var: /Applications/Ghostty.app/Contents/Resources
info(io_exec): shell integration automatically injected shell=termio.shell_integration.Shell.fish

If you see any of the following, something is not working correctly. The main culprit is usually that GHOSTTY_RESOURCES_DIR is not pointing to the right place.

ghostty terminfo not found, using xterm-256color

or

shell could not be detected, no automatic shell integration will be injected

Switching Shells with Shell Integration

Automatic shell integration as described in the previous section only works for the initially launched shell when Ghostty is started. If you switch shells within Ghostty, i.e. you manually run bash or you use a command like nix-shell, the shell integration will be lost in that shell (it will keep working in the original shell process).

To make shell integration work in these cases, you must manually source the Ghostty shell-specific code at the top of your shell configuration files. Ghostty will automatically set the GHOSTTY_RESOURCES_DIR environment variable when it starts, so you can use this to (1) detect your shell is launched within Ghostty and (2) to find the shell-integration.

For example, for bash, you'd put this at the top of your ~/.bashrc:

# Ghostty shell integration
if [ -n "$GHOSTTY_RESOURCES_DIR" ]; then
    builtin source "${GHOSTTY_RESOURCES_DIR}/shell-integration/bash/ghostty.bash"
fi

This must be at the top of your bashrc, not the bottom. The same goes for any other shell.

Roadmap and Status

The high-level ambitious plan for the project, in order:

#	Step	Status
1	Standards-compliant terminal emulation	⚠️
2	Competitive performance	✅
3	Basic customizability -- fonts, bg colors, etc.	✅
4	Richer windowing features -- multi-window, tabbing, panes	✅
5	Native Platform Experiences (i.e. Mac Preference Panel)	⚠️
6	Windows Terminals (including PowerShell, Cmd, WSL)	❌
N	Fancy features (to be expanded upon later)	❌

Additional details for each step in the big roadmap below:

Standards-Compliant Terminal Emulation

I am able to use this terminal as a daily driver. I think that's good enough for a yellow status. There are a LOT of missing features for full standards compliance but the set that are regularly in use are working pretty well.

Competitive Performance

We need better benchmarks to continuously verify this, but I believe at this stage Ghostty is already best-in-class (or at worst second in certain cases) for a majority of performance measuring scenarios.

For rendering, we have a multi-renderer architecture that uses OpenGL on Linux and Metal on macOS. As far as I'm aware, we're the only terminal emulator other than iTerm that uses Metal directly. And we're the only terminal emulator that has a Metal renderer that supports ligatures (iTerm uses a CPU renderer if ligatures are enabled). We can maintain roughly 100fps under heavy load and 120fps generally -- though the terminal is usually rendering much lower due to little screen changes.

For IO, we have a dedicated IO thread that maintains very little jitter under heavy IO load (i.e. cat <big file>.txt). On benchmarks for IO, we're usually top of the class by a large margin over popular terminal emulators. For example, reading a dump of plain text is 4x faster compared to iTerm and Kitty, and 2x faster than Terminal.app. Alacritty is very fast but we're still ~15% faster and our app experience is much more feature rich.

Richer Windowing Features

The Mac app supports multi-window, tabbing, and splits.

The Linux app built with GTK supports multi-window and tabbing. Splits will come soon in a future update.

The Linux app built with GLFW is aimed for a lighter weight experience, particularly for users of tiled window managers who don't want multi-window or tabs as much. The GLFW-based app supports multi-window but does not support tabs or splits.

Native Platform Experiences

Ghostty is a cross-platform terminal emulator but we don't aim for a least-common-denominator experience. There is a large, shared core written in Zig but we do a lot of platform-native thing:

The macOS app is a true SwiftUI-based application with all the things you would expect such as real windowing, menu bars, a settings GUI, etc.
macOS uses a true Metal renderer with CoreText for font discovery.
The Linux app comes in both a GTK and GLFW flavor. The GTK flavor is more feature rich and looks and acts like any other desktop application. Both Linux versions use OpenGL.

There are more improvements to be made. The macOS settings window is still a work-in-progress. Similar improvements will follow with Linux+GTK. The Linux+GLFW build will remain lightweight.

Developing Ghostty

Ghostty is built using both the Zig programming language as well as the Zig build system. At a minimum, Zig and Git must be installed. For Nix users, a shell.nix is available which includes all the necessary dependencies pinned to exact versions.

Note: Zig nightly is required. Ghostty is built against the nightly releases of Zig. I plan on stabilizing on a release version when I get closer to generally releasing this to ease downstream packagers. During development, I'm sticking to nightly Zig. You can find binary releases of nightly builds on the Zig downloads page.

Install dependencies by running make:

$ make

With Zig installed, a binary can be built using zig build:

$ zig build
...

$ zig-out/bin/ghostty

This will build a binary for the currently running system (if supported). Note: macOS does not result in a runnable binary with this command. macOS builds produce a library (libghostty.a) that is used by the Xcode project in the macos directory to produce the finally Ghostty.app.

On macOS, you can use zig build -Dapp-runtime=glfw run for a quick GLFW-based app for a faster development cycle while developing core terminal features. Note that this app is missing many features and is also known to crash in certain scenarios, so it is only meant for development tasks.

Other useful commands:

zig build test for running unit tests.
zig build run -Dconformance=<name> run a conformance test case from the conformance directory. The name is the name of the file. This runs in the current running terminal emulator so if you want to check the behavior of this project, you must run this command in ghostty.

Compiling a Release Build

The normal build will be a debug build which includes a number of safety features as well as debugging features that dramatically slow down normal operation of the terminal (by as much as 100x). If you are building a terminal for day to day usage, build a release version:

$ zig build -Doptimize=ReleaseFast
...

You can verify you have a release version by checking the filesize of the built binary (zig-out/bin/ghostty). The release version should be less than 5 MB on all platforms. The debug version is around 70MB.

Mac `.app`

To build the official, fully featured macOS application, you must build on a macOS machine with XCode installed:

$ zig build -Doptimize=ReleaseFast
$ cd macos && xcodebuild

This will output the app to macos/build/Release/Ghostty.app. This app will be not be signed or notarized. Note that official continuous builds are available that are both signed and notarized.

When running the app, logs are available via macOS unified logging such as Console.app. The easiest way I've found is to just use the CLI:

$ sudo log stream --level debug --predicate 'subsystem=="com.mitchellh.ghostty"'
...

Languages

Zig 83.2%

Swift 8%

C 6.5%

Shell 0.7%

C++ 0.5%

Other 0.9%

README.md

ghostty

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