Pylon

A Metal-accelerated terminal emulator built for Claude Code. Track sessions, monitor usage, and manage everything from one window.

Why Pylon?

If you use Claude Code heavily, you know the pain: multiple terminal windows, one for each session, with no way to see which is doing what. A separate TUI to check your token usage. Another tool to track active sessions. Tab-switching chaos.

Pylon puts it all in one place. A fast terminal with a built-in side panel that shows your active Claude sessions and real-time API usage across all your accounts. Click a session to jump to it. See at a glance who's working, who's idle, and how much capacity you have left.

Features

Terminal

• Metal GPU-accelerated rendering with Retina-resolution glyph rasterization
• Pixel-perfect box-drawing characters (40+ rendered programmatically, not from fonts)
• Hack Nerd Font by default (same as Warp)
• Native macOS tabs (Cmd+T, Cmd+W, Cmd+1-9)
• Click-to-position cursor on the prompt line
• Solarized Dark theme

Sessions Panel

• Auto-discovers running Claude Code sessions via process scanning (every 5s)
• Shows status: green dot = idle, yellow dot = working (based on JSONL activity)
• Displays session topic, project folder, and session ID
• Click to switch tabs, bring windows to front, or unminimize
• Double-click to rename a session
• Correctly handles multiple sessions in the same directory

Usage Panel

• Tracks 5-hour and 7-day utilization across all your Claude accounts
• Color-coded progress bars (green/yellow/red)
• Live countdown timers until rate limit resets
• Polls the Anthropic API every 3 minutes
• Supports OAuth and session key authentication

Polish

• Dark title bar that matches the terminal theme
• Per-window sidebar width (drag to resize)
• Sidebar scrolling for long content
• Consistent rendering across Retina and non-Retina displays
• GPU frame synchronization to prevent scroll ghosting

Install

# Clone and build
git clone https://github.com/DSado88/pylon.git
cd pylon
cargo build --release

# Install as macOS app
./install.sh

Then open Pylon from Spotlight, Launchpad, or /Applications/Pylon.app.

Requirements

• macOS 14+
• Rust toolchain (rustup)
• Hack Nerd Font (install via brew install font-hack-nerd-font)

Usage Tracking Setup

Pylon reads account credentials from the same config as claude-tracker. To set up usage monitoring:

1. Create the config file:

# ~/.config/claude-tracker/config.toml

[settings]
poll_interval_secs = 180

[[accounts]]
name = "your-email@example.com"
org_id = "your-org-uuid"
auth_method = "oauth"

2. Store your OAuth token in the macOS Keychain:

# If you have claude-tracker installed, use its login flow:
# Press 'L' in claude-tracker to authenticate via OAuth

# Or import from Claude Code's existing keychain entry:
# Press 'i' in claude-tracker to import

The org_id is your Anthropic organization UUID. The OAuth token is stored in the macOS Keychain under the claude-tracker service name.

Without this config, the Usage panel will show "Loading..." — the terminal works fine without it, you just won't see usage stats.

Keyboard Shortcuts

Shortcut	Action
Cmd+T	New tab
Cmd+W	Close tab
Cmd+N	New window
Cmd+1-9	Switch to tab N
Cmd+B	Toggle sidebar
Cmd+Shift+B	Cycle sidebar panel (Sessions/Usage/Shortcuts)
Cmd+Shift+R	Rename tab
Cmd+Plus/Minus	Adjust font size
Cmd+0	Reset font size
Cmd+C	Copy selection (or Ctrl+C if no selection)
Cmd+V	Paste (with bracketed paste support)

Architecture

Pylon is written in Rust with these key components:

• GPU rendering: Metal vertex/fragment shaders with a glyph texture atlas
• VT parsing: SIMD-accelerated via the vte crate with a fast ASCII path
• PTY management: Direct fork/exec with proper signal handling
• Async polling: Tokio runtime for session discovery and API queries
• Native macOS integration: objc2 bindings for window appearance, tab management, and clipboard

The terminal grid uses a dirty-row bitfield to minimize GPU uploads — only changed rows are re-written each frame. Scrollback is stored in a ring buffer with configurable capacity (default 10,000 lines).

Related Tools

Pylon integrates functionality from two standalone TUIs that I built and maintain separately. If you want focused, stable tools instead of the all-in-one approach:

• claude-tracker — Rust/ratatui TUI for monitoring Claude API usage across multiple accounts. OAuth login, token refresh, color-coded progress bars, live countdown timers. Stable and production-ready.

• claude-sessions — Python/Textual TUI for tracking active Claude Code sessions. Process discovery, window matching, AI-generated topic summaries via Apple Intelligence, session history in SQLite. Stable and production-ready.

Pylon combines both into a single terminal with a side panel, but the standalone tools are more mature and feature-complete if you just need one or the other.

License

MIT