ghostty
GPU-accelerated terminal emulator pushing modern features.
About
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: Alpha. It is a minimal terminal emulator that can be used for day-to-day work. It is missing many nice to have features but as a minimal terminal emulator it is ready to go. I've been using it full time since April 2022.
Roadmap and Status
The high-level ambitious plan for the project, in order:
| # | Step | Status |
|---|---|---|
| 1 | Standards-compliant terminal emulation | ⚠️ |
| 2 | Competitive rendering performance (not the fastest, but fast enough) | ✅ |
| 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) | ❌ |
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 Rendering Performance
I want to benchmark this better, but we can maintain roughly 100fps under heavy load and 120fps generally. 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.
Richer Windowing Features
We support multi-window and tabbing on Mac. We will support panes/splits in the future and we'll continue to improve multi-window features.
Native Platform Experiences
Ghostty is a cross-platform terminal emulator but is meant to feel native on each platform it runs on. On macOS, this means having a preferences window that is a native Mac window (versus only file-based configuratin). On Linux this means having a GTK option that has richer windowing features. Etc.
Right now, we're focusing on the macOS experience first. We are using Cocoa with Metal and rendering text with CoreText. We will be working to improve the windowing experience here.
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. You can find binary releases of nightly builds on the Zig downloads page.
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).
You can cross compile by setting -Dtarget=<target-triple>. For example,
zig build -Dtarget=aarch64-macos will build for Apple Silicon macOS. Note
that not all targets supported by Zig are supported.
Other useful commands:
zig build testfor running unit tests.zig build run -Dconformance=<name>run a conformance test case from theconformancedirectory. Thenameis 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 -Drelease-fast
...
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
When targeting macOS, a macOS application bundle will be created at
zig-out/Ghostty.app. This can be copied as-is and used like a normal app.
This app will be not be signed or 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"'
...