When Joan Muthui arrived at a Rotary vocational fair in January 2025, she had borrowed Sh500 from her workplace’s petty cash fund to pay for a stand. She had spent the weekend labelling moisturiser tubes on her bed alongside her two sons and had no idea whether anyone would buy them.

By the time the evening session closed, her phone showed Sh9,600 in mobile money receipts.“What? You mean it’s working?” she recalls thinking. “I have never looked back.”