create a company/person with custom fields with the highrise api

Highrise::Company.create({
  name: "My Company",
  subject_datas: [
    {
      subject_field_id: 123456,
      value: Time.now.strftime('%d.%m.%Y %H:%M:%S')
    },
    {
      subject_field_id: 7891234,
      value: 'API SYNC'
    }
  ]
})

get the subject field ids from the api or inspect the html in you highrise custom field options.

PS: the Highrise API is crap