uuidv7.swift

import Foundation

extension UUID {
    static func v7() -> Self {
        // random bytes
        var value = (
            UInt8(0),
            UInt8(0),
            UInt8(0),
            UInt8(0),
            UInt8(0),
            UInt8(0),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255),
            UInt8.random(in: 0...255)
        )

        // current timestamp in ms
        let timestamp: Int = .init(Date().timeIntervalSince1970 * 1000)

        // timestamp
        value.0 = .init((timestamp >> 40) & 0xFF)
        value.1 = .init((timestamp >> 32) & 0xFF)
        value.2 = .init((timestamp >> 24) & 0xFF)
        value.3 = .init((timestamp >> 16) & 0xFF)
        value.4 = .init((timestamp >> 8) & 0xFF)
        value.5 = .init(timestamp & 0xFF)

        // version and variant
        value.6 = (value.6 & 0x0F) | 0x70
        value.8 = (value.8 & 0x3F) | 0x80

        return UUID(uuid: value)
    }
}

let uuidVal: UUID = .v7()
print(uuidVal)