I really enjoyed reading your article. I went through it writing out your code. I agree with Alexander Kosenkov’s comment. I found it easier to simply write

employee {
    name = "David"
    id = "343"
    title = "Super Boss"
    salary = 32332223

}

So, the builder is simplified to:

class EmployeeBuilder {
    var name: String = ""
    var id: String = ""
    var title: String = ""
    var salary: Int = 0

    fun build() = Employee(name, id, title, salary)

}

I liked your idea of the EmployeeListBuilder. It is a good idea. Then all of the employee declarations must appear inside the employeesblock. It helps to keep the declarations more organized.

Thank you for your well-written article.