MacNTop

January 22, 2026 · View on GitHub

A macOS menu bar system monitor with retro CRT terminal aesthetics.


Menu Bar Popover	Floating Window

Features

Live Monitoring

CPU Usage - Per-core usage with sparkline graphs
Memory - Active, wired, compressed breakdown with segmented bar
Network - Upload/download speeds with real-time sparklines
Disk - Volume usage and I/O speeds
Processes - Top 10 by CPU or memory usage

Retro CRT Aesthetics

Phosphor glow effects on text
Scanline overlay
Vignette darkening at edges
Multiple color themes

Themes

Retro Green - Classic green phosphor CRT
Amber CRT - Warm amber terminal
Blue Ice - Cool blue tones
Matrix - Bright green on black
Dracula - Purple/pink dark theme
Light - Light mode for daytime

Installation

Requirements

macOS 14.0 (Sonoma) or later
Swift 6.0+ / Xcode 16+ (for building)

Build from Source

git clone https://github.com/CorvidLabs/MacNTop.git
cd MacNTop
swift build -c release

The built app will be at .build/release/MacNTop.

Run

swift run

Or after building:

.build/release/MacNTop

Usage

Left-click - Toggle the dashboard popover
Right-click - Open context menu

Open in Window - Detach dashboard to a floating window
Theme - Select from 6 color themes
About MacNTop - Version info
Quit MacNTop - Exit the app

Window Mode

The dashboard can be opened in a standalone floating window that stays on top:

Right-click → "Open in Window"
Window persists across spaces
Receives live updates like the popover
Right-click → "Close Window" to return to popover-only mode

Dashboard

CPU/MEM toggle in process list - Click to sort by CPU or Memory
Scroll to see all sections

Keyboard Shortcuts

⌘W - Toggle window mode (from context menu)
⌘Q - Quit (from context menu)

Architecture

MacNTop/
├── Sources/MacNTop/
│   ├── App/
│   │   ├── AppDelegate.swift          # Entry point
│   │   └── Application+State.swift    # AppState theme management
│   ├── MenuBar/
│   │   ├── StatusBarController.swift  # NSStatusItem + popover + window
│   │   └── StatusBarIconRenderer.swift
│   ├── Models/                        # Sendable data models
│   ├── Services/                      # Actor-based monitors
│   ├── Core/
│   │   └── MetricsCoordinator.swift   # Orchestrates collection
│   ├── Views/
│   │   ├── DashboardWindow.swift      # Standalone floating window
│   │   ├── DashboardView.swift        # Main dashboard layout
│   │   └── ...                        # Component views
│   └── Utilities/
│       └── ByteFormatter.swift
├── Tests/MacNTopTests/                # Unit tests
└── Package.swift

Key Technologies

Swift Concurrency - Actors for thread-safe monitoring
AppKit - Native macOS UI
AppState - State management and persistence
IOKit - Low-level system metrics

System APIs Used

Metric	API
CPU	`host_processor_info()`
Memory	`host_statistics64(HOST_VM_INFO64)`
Network	`getifaddrs()` with `if_data`
Disk	`statfs()`, IOKit `IOBlockStorageDriver`
Processes	`proc_listallpids()`, `proc_pidinfo()`