Horizon

Horizon is a GPU-accelerated terminal board built in Rust that organizes terminal sessions on an infinite 2D canvas. Instead of tabs or tiled layouts, every terminal lives as a panel that can be placed, resized, and grouped freely across the workspace surface.

The core rendering engine combines eframe/egui for the immediate-mode UI with wgpu for GPU-accelerated graphics across Vulkan, Metal, DX12, and OpenGL backends. Terminal emulation is powered by the Alacritty terminal engine, providing 24-bit color, mouse reporting, scrollback, alt-screen support, and Kitty keyboard protocol compatibility.

Horizon supports multiple color-coded workspaces to separate different contexts like frontend, backend, and monitoring. Each workspace can auto-arrange its panels using five layout modes: rows, columns, grid, stack, and cascade. A minimap in the corner provides spatial orientation and click-to-jump navigation across the canvas.

AI agent integration is a first-class feature. Horizon includes dedicated panel types for Claude Code and Codex sessions that persist and auto-resume between application restarts. A live usage dashboard tracks token spend across all active agent sessions, giving developers visibility into their AI tool consumption.

The built-in git status panel watches repositories in the background, displaying changed files, inline diffs, and hunk-level detail without requiring context switches to a separate tool. Smart detection features let users Ctrl+click URLs to open them in a browser or hover file paths to jump directly to them.

Configuration is handled through a YAML file at ~/.horizon/config.yaml, where users define workspaces, panel presets, and feature flags. A live settings editor accessible via Ctrl+, provides YAML syntax highlighting and instant preview, applying changes to the canvas in real time.

Session persistence ensures that workspaces, panel positions, scroll positions, and terminal history are restored exactly as they were when the application was last closed. The application ships as a standalone binary for Linux x64, macOS arm64 and x64, and Windows x64, with no external dependencies required. It can also be built from source using Rust 1.85 or later.

Horizon uses SQLite for local state management, supports Wayland and X11 on Linux, and includes a profiling build profile for performance analysis. The project is licensed under MIT and hosted on GitHub with an active CI pipeline.