A ratib is a fixed arrangement, a set of Quranic verses and short formulae recited in a settled order and a settled number of repetitions. The one al-Haddad composed in the 1650s is short enough to finish in a quarter of an hour and has been recited after the evening prayer in Hadrami communities ever since. Its portability is the point. It needs no shaykh present, no instrument and no building, and it can be led by whoever is in the room, which makes it a devotion that travels in a household rather than in an institution.
That is precisely what happened. Hadrami men left the valley in large numbers for the ports of East Africa, the Malabar coast, the Malay peninsula and the Indonesian archipelago, as traders, teachers and religious specialists, and they took short texts with them. By the nineteenth century the Ratib al-Haddad was being recited in Zanzibar, in Kerala, in Palembang and in Singapore, and printed editions moved along the same routes. His Wird al-Latif, a morning and evening litany, spread the same way, and both are still in print in several scripts.
Nothing organised the diffusion. Families moved, carried books and taught their children the same order of words, which is a useful corrective to accounts of Sufi expansion that assume a missionary structure behind every spread.