Ghostty Ambient

Ambient light-aware theme selector for Ghostty with Bayesian preference learning.

Quick Install

curl -fsSL https://raw.githubusercontent.com/gezibash/ghostty-ambient/main/install.sh | bash

This installs the package and sets up the learning daemon to run automatically.

Features

• Ambient Light Sensing: Reads your Mac's ambient light sensor to suggest themes appropriate for current lighting
• Bayesian Learning: Learns your color preferences over time—which themes you prefer in different contexts
• Context-Aware: Considers time of day, weather, system dark/light mode, and power source
• Theme Generation: Generates custom themes from your learned preferences (background, contrast, saturation)
• Portable Profiles: Export/import your learned preferences across devices

Installation

# Using uv (recommended)
uv add ghostty-ambient

# Using pip
pip install ghostty-ambient

Quick Start

Interactive Theme Picker

ghostty-ambient

Shows a picker with theme recommendations based on current conditions. Select a theme to apply it.

Run the Learning Daemon

ghostty-ambient --daemon

Runs in the background, learning your preferences by observing which themes you use in different contexts. Only records when Ghostty is the frontmost application.

Generate Your Ideal Theme

ghostty-ambient --ideal

Generates and applies a custom theme optimized for your current context, based on learned preferences:

• Background color (light vs dark)
• Contrast (how much difference between background and foreground)
• Chroma (color saturation)

CLI Reference

ghostty-ambient              # Interactive theme picker
ghostty-ambient --ideal      # Generate and apply optimal theme
ghostty-ambient --set NAME   # Set theme by name
ghostty-ambient --stats      # Show learned preferences
ghostty-ambient --export-profile FILE  # Export preferences
ghostty-ambient --import-profile FILE  # Import preferences
ghostty-ambient --favorite   # Mark current theme as favorite
ghostty-ambient --dislike    # Mark current theme as disliked
ghostty-ambient --sensors    # Show available light sensors
ghostty-ambient --setup      # Configure location (for weather)

Daemon Management

ghostty-ambient --status              # Check daemon status
ghostty-ambient --start               # Start daemon (5m interval)
ghostty-ambient --start --freq 1m     # Start with custom interval
ghostty-ambient --stop                # Stop daemon
ghostty-ambient --restart             # Restart daemon
ghostty-ambient --logs                # Tail daemon logs

Run Daemon Inline

ghostty-ambient --daemon              # Run daemon in foreground
ghostty-ambient --daemon --interval 30s  # Custom interval

How It Works

Bayesian Preference Learning

The system learns three key properties of your theme preferences:

Property	What It Learns
Background L	Light vs dark theme preference (LAB lightness)
Contrast	Preferred difference between background and foreground
Chroma	Preferred color saturation in the palette

These are learned per-context:

• Time of day (morning, afternoon, evening, night)
• Ambient light (dim, office, bright, daylight)
• System appearance (light mode, dark mode)
• Power source (AC, battery)

View Your Learned Preferences

ghostty-ambient --stats

By Time of Day
╭───────────┬───────┬────┬──────────┬────────┬─────╮
│           │ Theme │  L │ Contrast │ Chroma │   n │
├───────────┼───────┼────┼──────────┼────────┼─────┤
│ Morning   │ light │ 97 │       84 │     49 │ 124 │
│ Afternoon │ light │ 97 │       86 │     50 │ 121 │
╰───────────┴───────┴────┴──────────┴────────┴─────╯

Portable Profiles

Export your learned preferences:

ghostty-ambient --export-profile ~/my-prefs.json

Import on another device:

ghostty-ambient --import-profile ~/my-prefs.json

Platform Support

Platform	Ambient Light Sensor	Theme Detection
macOS	Native (via als helper)	Full support
Linux	Via iio-sensor-proxy	Full support
Windows	Via Windows SDK	Partial support

macOS Ambient Light Sensor

The bundled als binary reads the ambient light sensor. To compile from source:

clang -framework IOKit -framework CoreFoundation als.m -o als

Daemon Management

The install script sets up a background daemon that learns your preferences. Use these commands to manage it:

ghostty-ambient --status              # Check if daemon is running
ghostty-ambient --start               # Start the daemon (default 5m interval)
ghostty-ambient --start --freq 30s    # Start with custom interval
ghostty-ambient --stop                # Stop the daemon
ghostty-ambient --restart             # Restart the daemon
ghostty-ambient --logs                # Tail daemon logs (Ctrl+C to exit)

Uninstall

curl -fsSL https://raw.githubusercontent.com/gezibash/ghostty-ambient/main/uninstall.sh | bash

Your learned preferences are preserved in ~/.config/ghostty-ambient/.

Development

# Clone and install dev dependencies
git clone https://github.com/gezibash/ghostty-ambient
cd ghostty-ambient
uv sync --all-extras

# Run tests
uv run pytest

# Run with verbose output
uv run ghostty-ambient --daemon --interval 30s

License

MIT License - see LICENSE for details.