package main import ( "fmt" "net/http" "os" ) func main() { fmt.Println("listening on port 3000") if err := http.ListenAndServe( "localhost:3000", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { _, err := w.Write([]byte("hello")) if err != nil { fmt.Println("oh no!") } }), ); err != nil { os.Exit(1) } }