SysBar

A lightweight macOS menu bar app that displays real-time system resource usage.

Features

• CPU — Total and per-core usage with spark-line history in the menu bar
• RAM — Used / total memory in GB
• GPU — Apple Silicon GPU utilization percentage
• Disk — Boot volume used / total space
• Network — Real-time upload and download speeds
• Battery — Level, charging status, and power source

Menu Bar

The menu bar icon shows a live CPU spark-line chart. Click to open the full metrics panel.

Requirements

• macOS 15+ (Sequoia)
• Apple Silicon Mac
• Xcode 16+ or Swift 6 toolchain

Build & Run

# Build
swift build
# Run
swift run SysBar
# Or open in Xcode
open Package.swift

Architecture

• Pure SwiftUI — MenuBarExtra with .window style, no AppKit bridges
• Zero dependencies — Uses system APIs only (Mach, IOKit, POSIX)
• Swift actors — Thread-safe data collection without manual locks
• Direct syscalls — host_processor_info, host_statistics64, statvfs, getifaddrs, IOKit registry

Project Structure

Sources/
├── SysBarApp.swift # Entry point, MenuBarExtra setup
├── Models/
│ ├── SystemMetrics.swift # Data structs (CPU, RAM, GPU, Disk, Network, Battery)
│ └── AppState.swift # Observable state with 2-second refresh loop
├── Services/
│ └── SystemMonitor.swift # Actor collecting all metrics via syscalls
├── Views/
│ ├── SysBarPanel.swift # Main dropdown panel
│ ├── MetricRow.swift # Reusable metric + progress bar component
│ └── SparkLine.swift # Canvas-based CPU spark-line
└── Utilities/
└── Formatters.swift # Byte, speed, and percentage formatting

License

MIT