What subjects did Usman dan Fodio write about during his later years at Sifawa?

During his later years at Sifawa, Usman dan Fodio dedicated himself to teaching and writing, producing a significant number of works that primarily addressed the practical challenges facing the Muslim community.1

His writings from this period included a series of books directed toward "the Brethren" (al-Ikhwān), which emerged from a dispute with the Bornu Empire and its administrator, Muḥammad al-Kanemi. Additionally, through his weekly Thursday night meetings, he used his platform to critique the post-jihad caliphate, specifically addressing concerns regarding the emergence of an oppressive ruling class within the new bureaucracy.1