https://go.dev/play/p/Gl7KqSKMMm2

proquint.go

//  Proquints: Identifiers that are Readable, Spellable, and Pronounceable
//  https://arxiv.org/html/0901.4016

package main

import (
	"bytes"
	"fmt"
	"regexp"
	"strings"

	"github.com/gofrs/uuid"
)

var (
	conse = [...]byte{'b', 'd', 'f', 'g', 'h', 'j', 'k', 'l', 'm', 'n',
		'p', 'r', 's', 't', 'v', 'z'}
	vowse = [...]byte{'a', 'i', 'o', 'u'}

	consd = map[byte]uint16{
		'b': 0, 'd': 1, 'f': 2, 'g': 3,
		'h': 4, 'j': 5, 'k': 6, 'l': 7,
		'm': 8, 'n': 9, 'p': 10, 'r': 11,
		's': 12, 't': 13, 'v': 14, 'z': 15,
	}

	vowsd = map[byte]uint16{
		'a': 0, 'i': 1, 'o': 2, 'u': 3,
	}
)

func IsProquint(str string) (bool, error) {
	exp := "^([abdfghijklmnoprstuvz]{5}-)*[abdfghijklmnoprstuvz]{5}$"
	ok, err := regexp.MatchString(exp, str)

	return ok, err
}

func Encode(buf []byte) string {
	var out bytes.Buffer

	for i := 0; i < len(buf); i = i + 2 {
		var n uint16 = (uint16(buf[i]) * 256) + uint16(buf[i+1])

		var (
			c3 = n & 0x0f
			v2 = (n >> 4) & 0x03
			c2 = (n >> 6) & 0x0f
			v1 = (n >> 10) & 0x03
			c1 = (n >> 12) & 0x0f
		)

		out.WriteByte(conse[c1])
		out.WriteByte(vowse[v1])
		out.WriteByte(conse[c2])
		out.WriteByte(vowse[v2])
		out.WriteByte(conse[c3])

		if (i + 2) < len(buf) {
			out.WriteByte('-')
		}
	}

	return out.String()
}

func Decode(str string) []byte {
	var (
		out  bytes.Buffer
		bits []string = strings.Split(str, "-")
	)

	for i := 0; i < len(bits); i++ {
		var x uint16 = consd[bits[i][4]] +
			(vowsd[bits[i][3]] << 4) +
			(consd[bits[i][2]] << 6) +
			(vowsd[bits[i][1]] << 10) +
			(consd[bits[i][0]] << 12)

		out.WriteByte(byte(x >> 8))
		out.WriteByte(byte(x))
	}

	return out.Bytes()
}

func main() {
	token, _ := uuid.NewV4()
	p := Encode(token.Bytes())
	fmt.Printf("%v => %v => %s\n", token.Bytes(), token, p)
	fmt.Printf("%s => %v\n", p, Decode(p))

	fmt.Println("\nLet's make a bunch of UUIDs to show it's easier to distinguish visually.\n")
	for i := 1; i <= 20; i++ {
		token, _ := uuid.NewV4()
		p := Encode(token.Bytes())
		fmt.Printf("%s <=> %s\n", token, p)
	}
}