private function createUsersTable()
    {
        Schema::create('users', function ($table) {
            foreach ($this->fields as $field => $value) {
                $query = $table->$value['type']($field);

                if (isset($value['extra'])) {
                    $query->$value['extra']();
                }
            }

            $table->foreign('role_id')->references('id')->on('roles');
            $table->timestamps();
            $table->softDeletes();
        });
    }