Fomatting numbers with golang.org/x/text/

main.go

package main

import (
    "golang.org/x/text/language"
    "golang.org/x/text/message"
)

func main() {
    p := message.NewPrinter(language.English)
    p.Printf("%d\n", 1000)

    // Output:
    // 1,000
}