Multiple goji instances about goji HOT 2 CLOSED

package main

import (
    "log"
    "net/http"
    "sync"

    "github.com/zenazn/goji/web"
)

func main() {

    a := web.New()
    a.Get("/", func(w http.ResponseWriter, r *http.Request) { w.Write([]byte("Server A root.")) })

    b := web.New()
    b.Get("/", func(w http.ResponseWriter, r *http.Request) { w.Write([]byte("Server B root.")) })

    var wg sync.WaitGroup

    wg.Add(1)
    go func() {
        log.Println("Server A")
        http.ListenAndServe(":9000", a)
    }()

    wg.Add(1)
    go func() {
        log.Println("Server B")
        http.ListenAndServe(":9001", b)
    }()

    wg.Wait()
}