Add and new column/attribute to sequelize model

Is there a way to add a new column to a model that has already been defined?

Something like:

var Agency = sequelize.define("agency", {
  agency_id: {
    type: DataTypes.STRING(255),
    primaryKey: true
  },
  agency_name: DataTypes.STRING(255),
  agency_url: DataTypes.STRING(255)
});

Agency.addColumn({ agency_lang: DataTypes.STRING(2) });

theoretically you could do Agency.rawAttributes.agency_lang =... and then call Agency.refreshAttributes. However, there is no guarantee that this will work in all cases, since refreshAttributes is not part of the public API.

Why do you need to alter the attributes after the model has been defined? Sequelize does not support automagically altering the table, so you'd need to DROP TABLE + CREATE TABLE to reflect the new structure in the DB