uuidv7

Generate UUID v7 strings, like 019212d3-87f4-7d25-902e-b8d39fe07f08.

``sh
uuidv7 > uuidv7.txt
`

`text
019212d3-87f4-7d25-902e-b8d39fe07f08
`

| 32-bit time | 16-bit time | 4 ver + 12 rnd | 2 var + 14 rnd | 16 rnd + 32 rnd |
| :------------------------: | :---------: | :------------: | :------------: | :----------------------------------------: |
| 01 92 12 d3 | 87 f4 | 7d 25 | 90 2e | b8 d3 9f e0 7f 08 |

Table of Contents

- Install
- In JavaScript
- UUIDv7 Spec
- By the Characters
- By the Bits
- Zig Build
- License

Install

Pre-built archives available for Mac, Linux, & Widows. \
Compile from source for FreeBSD, OpenBSD, etc.

1. Download from GitHub Releases:

2. Extract
3. Place in your PATH

`sh
b_triplet='x86_64-linux-musl'
curl -L -O https://github.com/coolaj86/uuidv7/releases/download/v1.0.0/uuidv7-v1.0.0-"$b_triplet".tar.gz
tar xvf ./uuidv7-v1.0.0-"$b_triplet".tar.gz
mv ./uuidv7 ~/bin/
`

JavaScript Version

Supports both import and require.

Extremely simple implementation that can be tuned for speed or memory
efficiency.

`sh
npm install --save @root/uuidv7
`

High-level API:

`js
import UUIDv7 from "@root/uuidv7";

let buffer = new Uint8Array(4096); // optional, if you need lots of UUIDs, and fast
UUIDv7.setBytesBuffer(buffer);

UUIDv7.uuidv7();
// 01922aa4-88ad-7cae-a517-a298a491d35c

UUIDv7.uuidv7Bytes();
// Uint8Array(16) [ 1, 146, 42, 176, 37, 122, 114, 189
// 172, 240, 1, 146, 42, 176, 37, 122 ]
`

Low-level API:

`js
let now = Date.now();
let ms64 = BigInt(now);
let bytes = new Uint8Array(16);
let start = 0;
globalThis.crypto.getRandomValues(bytes);

void UUIDv7.fill(bytes, start, ms64);

console.log(bytes);
// Uint8Array(16) [ 1, 146, 42, 176, 37, 122, 114, 189
// 172, 240, 1, 146, 42, 176, 37, 122 ]
`

`js
let uuidv7 = UUIDv7.format(bytes);
console.log(uuidv7);
// 01922aa4-88ad-7cae-a517-a298a491d35c
`

UUIDv7 Spec

By the Characters

There are 36 characters total: 32 hex (0123456789abcdef) + 4 dashes (-)

`text
8 time 4 time 1v + 3ra ½v + 3½rb 12 random b
019212d3 - 87f4 - 7d25 - 902e - b8d39fe07f08
`

- 8ch hex time high
- -
- 4ch hex time low
- -
- 4ch hex version + "random a"
- 1ch hex version: 7
- 3ch hex "random a"
- -
- 4ch hex variant + "random b"
- 1ch hex version: 8, 9, a, b
- 3ch hex "random b"
- -
- 12ch hex randam a
- 4ch hex random a
- 8ch hex random a

By the Bits

`text
48 time 4ver, 12ra 2var, 14rb random b
019212d3-87f4 - 7d25 - 902e - b8d39fe07f08
`

- 48 bits of timestamp
- 32-bit high (minutes to years)
- 16-bit low (seconds & milliseconds)
- 16 bits of version + random
- 4-bit version (0b0111)
- 12-bit random
- 64-bits variant + random
- 2-bit variant (0b10)
- 62-bit random

Build

See .

Builds with zig v0.13 and the v0.14 previews so far.

`sh
curl https://webi.sh/zig@0.13 | sh
source ~/.config/envman/PATH.env
`

`sh
zig build-exe ./uuidv7.zig -O ReleaseSmall -femit-bin="uuidv7"

for b_target in x86-linux-musl aarch64-macos-none x86_64-windows-gnu; do
zig build-exe ./uuidv7.zig -O ReleaseSmall \
-target "${b_target}" -femit-bin="uuidv7-${b_target}"
done
``

License

Copyright 2024 AJ ONeal

This Source Code Form is subject to the terms of the Mozilla Public \
License, v. 2.0. If a copy of the MPL was not distributed with this \
file, You can obtain one at https://mozilla.org/MPL/2.0/.