Sheikh Mazrui wrote many books on islam in Swahili and Arabic including the Swahili translation of Suratul Al-Baqara, Suratul Al-Imran and Suratul An-Nisaa. He used to write articles in the Al-Manar la Al-Azhar University Magazine, until he later on started his own magazine. He was such a great teacher and role model, that his students went out to be great contributors to Islam such as Sheikh Abdala swaleh farsi AKA Sheikh Abdullah Saleh Al-farsy and Maalim Ghazali who founded Madrasatul Ghazal now Mbaraki Girls Primary School. The sheikh was also a strong proponent of women education, which was something not much practiced during his time, and encouraged many families to educate their daughters.
He started out his career in 1910 working as a clerk for the Kadhi(Muslim Judge) of Mombasa, until 1919 when he moved on to teach Arabic at an Arab school in Mombasa. In 1921,he went back to being a clerk for the Kadhi of Mombasa until 1932 when he became the kadhi of Mombasa. In 1937 he became the Kadhi of Kenya.
The mufti passed away in 1947, his death affected many, as he was such a power force and an inspiration in the region.May Allah grant him a high place in Jannah.
Source: Maisha Ya Sh. Al-Amin bin Ali Mazrui (1891-1947) by Ghalib Yusuf Tamim