Get macOS machine UUID (Swift 5)

SystemUUID.swift

// SPDX-License-Identifier: MIT
// MIT Software License: https://opensource.org/licenses/MIT
// Copyright Vadim Piven <[email protected]>

import Foundation
import IOKit

func getSystemUUID() -> String? {
    let platformExpert = IOServiceGetMatchingService(
        kIOMainPortDefault,
        IOServiceMatching("IOPlatformExpertDevice")
    )
    guard platformExpert != 0 else { return nil }
    defer { IOObjectRelease(platformExpert) }
    
    return IORegistryEntryCreateCFProperty(
        platformExpert,
        kIOPlatformUUIDKey as CFString,
        kCFAllocatorDefault,
        0
    ).takeUnretainedValue() as? String
}

Credits to https://gist.github.com/ericdke/ed2d8bd3d127c25bcc6b