package main

import (
	"fmt"
	"log"

	"github.com/valyala/fasthttp"
)

func main() {
	err := fasthttp.ListenAndServe("127.0.0.1:12345", handler)
	if err != nil {
		log.Fatalf("Error in ListenAndServe: %s", err)
	}
}

func handler(ctx *fasthttp.RequestCtx) {
	fmt.Fprintf(ctx, "HelloWorld")
}