How two high school sweethearts built an AI company for farmers

Before Joseph Simukoko introduced me to Mwiche Mukoma, we had already spent nearly half an hour talking at Nairobi Street Kitchen. The conversation wandered from Zambian politics to African immigration, from why the continent still struggles to trade with itself to the industries that could define its economic future. 

Simukoko speaks the way some people sprint—leaning forward, tugging at…