Nigerian fintech Gigbanc is winding down after three years of building cross-border payment products for freelancers — unable to raise fresh capital in a market that has quietly turned hostile to early-stage startups. Customers have until July 31 to convert balances and withdraw. This isn't an isolated failure: Chimoney, another Nigerian-founded cross-border payments startup, shut down in May for the exact same reason. The macro picture is brutal. Across Africa, disclosed...