Json writer emulating type classes

jsonwriter.sc

sealed trait json
final case class jsString(get: String) extends json
final case class jsObject(get: Map[String, json]) extends json
final case class jsNumber(get: Double) extends json
case object jsNull extends json

trait JsonWriter[A] {
  def write(value: A): json

}

// the instances
final case class Person(name: String, email: String)

object jsonWriterInstances {

  implicit val stringWriter: JsonWriter[String] = new JsonWriter[String] {
    def write(value: String): json = {
      jsString(value)
    }
  }

  implicit val personWriter: JsonWriter[Person] =
    new JsonWriter[Person] {
      def write(value: Person): json = {
        jsObject(
          Map(
            "name" -> jsString(value.name),
            "email" -> jsString(value.email)
          )
        )
      }
    }
}

object json {
  def toJson[A](value: A)(implicit w: JsonWriter[A]): json =
    w.write(value)
}

json.toJson("Rogers")(jsonWriterInstances.stringWriter)

val pp = Person("movers name", "[email protected]")
json.toJson(pp)(jsonWriterInstances.personWriter)