Sequelize composite unique constraint

Defining model:

export default function(sequelize, DataTypes) {
   return sequelize.define('Item', {
       minor: DataTypes.INTEGER,
       major: DataTypes.INTEGER,
   });
}

Can I define the pair minor and major as a composite UNIQUE constraint?

Recently, in V4, Sequelize has a method addConstraint on the query interface:

queryInterface.addConstraint('Items', {
  fields: ['minor', 'major'],
  type: 'unique',
  name: 'custom_unique_constraint_name'
});

queryInterface.createTable('Item', {
    minor: {
        type: Sequelize.INTEGER,
    },
    major: {
        type: Sequelize.INTEGER,
    }
}, {
    uniqueKeys: {
        Items_unique: {
            fields: ['minor', 'major']
        }
    }
});