ULBar — the menu bar stats app you own

// 01 ULBar 1.1.3 — datasheet

Actually native. Actually tiny.

AppKit and direct syscalls. No Electron, no helper daemons, no subprocesses, and not a single network call of its own. The monitor costs less than what it monitors.

CPU

host_processor_info

Total %, user/sys split, load averages in the dropdown.

GPU

IOAccelerator

Device utilization straight from IOKit.

Memory

host_statistics64

Used/total gigs — Activity Monitor's exact formula.

Network

sysctl IFLIST2

64-bit kernel counters. Live rates plus session totals.

Source

One Swift file

The entire app, commented. Every stat is a small sampler class.

Dependencies

Zero

Apple frameworks only. Builds with the free command-line tools.

Network calls

Zero

Reads the kernel, never the internet. Nothing phones home.

Footprint

<60 MB

One timer, four samplers, a rounding error of CPU.

Tick

2 seconds

OS-coalesced wakeups. Dropdown rows update only while open.

Install

bash install.sh

Your Mac compiles and signs it locally. No Xcode project.

On reboot

Registers as a login item via SMAppService. Toggleable from the menu.

License

Lifetime

Every Mac you personally own. Updates included.

// 02 what the money buys

The source is the product.

Your $9.95 buys a zip of clean, commented Swift that builds with one command. Want disk usage? Temperatures? Battery? Point your AI agent at main.swift and ask — adding a stat is adding a class and a row.

ULBar — zsh — 80×20

$ unzip ULBar-1.1.3.zip && cd ULBar
$ bash install.sh
Built build/ULBar.app
Installed and launched /Applications/ULBar.app

// Every stat is a sampler. Add yours.
final class GPUSampler {
    func sample() -> Double? {
        // IOKit → "Device Utilization %"
    }
}

// 03 the bands

Color tells you before numbers do.

Load values band from green to red so a glance is enough. Download climbs through greens to a gigabit glow; upload runs orange to red — always bright, only the hue changes with speed. Every threshold is one constant in the source.

simulated load40%

0255075100

cruising < 25% working 25–50% busy 50–75% pegged > 75%

// 04 one price

$9.95once, forever

Full Swift source — the whole app
One-command build & install scripts
App icon and brand assets included
Lifetime personal license, updates included
Modify it freely — by hand or by agent

// 05 questions

What exactly do I get?

A zip: Sources/main.swift (the entire app), build.sh, install.sh, the app icon, a README, and your license. Pay, download, done.

What do I need to run it?

macOS 13 or later, Apple Silicon or Intel, and the free Xcode Command Line Tools (xcode-select --install). Then bash install.sh builds and installs it.

Why source instead of a signed download?

Because owning the code is the feature. Your Mac builds and signs it locally, you can read every line of what runs on your machine, and you — or your AI agents — can change anything.

Can I use it on more than one Mac?

Yes — the license covers every machine you personally own or use. It just doesn't cover redistributing or reselling the code.

What if it doesn't work for me?

Reply to your Stripe receipt email within 14 days and we'll refund you.