libraryDependencies += "io.monix" %% "newtypes-core" % "0.2.3"

import monix.newtypes._

// Just for deriving type class instances
import cats._
import cats.implicits._

type Firstname = Firstname.Type
object Firstname extends NewtypeWrapped[String] {
  implicit val eq: Eq[Firstname] = derive
}

// Usage:
val name = Firstname("Alex")

// Coercing back into String:
name.value