A DeriveGen[A] can derive a generator of A values. Implicit instances of DeriveGen are automatically provided for standard types and algebraic data types made up of standard types. For example, here is how you can automatically derive generators for case classes and sealed traits:

final case class Point(x: Double, y: Double)

val genPoint: Gen[Any, Point] = DeriveGen[Point]

sealed trait Color
case object Red   extends Color
case object Green extends Color
case object Blue  extends Color

val genColor: Gen[Any, Color] = DeriveGen[Color]

You can derive generators that include your own custom types by providing an implicit DeriveGen instance for your type using a generator and the instance method.