A builder can allow you create different kinds of objects from a common stem. They don't have to be bags of properties. Say, SQLAlchemy is all built on chainin

A builder can allow you create different kinds of objects from a common stem. They don't have to be bags of properties. Say, SQLAlchemy is all built on chaining builder-like methods, which make one of the finest DSLs that translates to SQL. In the end, you build a representation of a SQL statement, but in no way could that work with named arguments alone. Instead, consider named arguments as nice shortcuts over curried functions.