Phantty

A Windows terminal written in Zig, powered by libghostty-vt for terminal emulation.

Features

• Ghostty's terminal emulation - Uses libghostty-vt for VT parsing and terminal state
• DirectWrite font discovery - Find system fonts by name
• FreeType rendering - High-quality glyph rasterization
• Per-glyph font fallback - Automatic fallback for missing characters
• Sprite rendering - Box drawing, block elements, braille patterns, powerline symbols
• Ghostty-style font metrics - Proper ascent/descent/line_gap from hhea/OS2 tables
• Theme support - Ghostty-compatible theme files (default: Poimandres)

Building

# Debug build (console subsystem, debug output visible)
make debug

# Release build (GUI subsystem, no background console window)
make release

# Clean build artifacts
make clean

Or directly with zig:

zig build                          # debug
zig build -Doptimize=ReleaseFast   # release

Usage

phantty.exe [options]

Options:
  --font, -f <name>            Set font (default: embedded fallback)
  --font-style <style>         Font weight (default: regular)
                                Options: thin, extra-light, light, regular,
                                         medium, semi-bold, bold, extra-bold, black
  --cursor-style <style>       Cursor shape (default: block)
                                Options: block, bar, underline, block_hollow
  --cursor-style-blink <bool>  Enable cursor blinking (default: true)
  --theme <path>               Load a Ghostty theme file
  --window-height <rows>       Initial window height in cells (default: 0=auto, min: 4)
  --window-width <cols>        Initial window width in cells (default: 0=auto, min: 10)
  --list-fonts                 List available system fonts
  --test-font-discovery        Test DirectWrite font discovery
  --help                       Show help

Configuration

Phantty uses a Ghostty-compatible config file format (key = value pairs). The config file is loaded from %APPDATA%\phantty\config.

Press Ctrl+, to open the config file in your default editor, or run phantty.exe --show-config-path to print the resolved path.

CLI flags override config file values (last wins).

Example config

font-family = Cascadia Code
font-style = regular
font-size = 14
cursor-style = bar
cursor-style-blink = true
theme = Poimandres
window-height = 32
window-width = 120
scrollback-limit = 10000000
custom-shader = path/to/shader.glsl
config-file = extra.conf

Available keys

Key	Default	Description
font-family	(none)	Font family name (falls back to embedded font if unset)
font-style	regular	Font weight: thin, extra-light, light, regular, medium, semi-bold, bold, extra-bold, black
font-size	12	Font size in points
cursor-style	block	Cursor shape: block, bar, underline, block_hollow
cursor-style-blink	true	Enable cursor blinking
theme	(none)	Theme name or absolute path (453 Ghostty themes built-in)
custom-shader	(none)	Path to a GLSL post-processing shader
window-height	`0$ (\text{auto})	\text{Initial} \text{height} \text{in} \text{cells} (\text{min}: 4, 0 = \text{auto} 80 \times 24)
$window-width`	`0$ (\text{auto})	\text{Initial} \text{width} \text{in} \text{cells} (\text{min}: 10, 0 = \text{auto} 80 \times 24)
$scrollback-limit`	10000000	Scrollback buffer limit in bytes
config-file	(none)	Include another config file (prefix with ? to make optional)

License

MIT