On “Kabibi” he connects breezily with the Tanzanian singer and thumb pianist Anania Ngoliga; on “Pakugyenda Balebauo,” also in Tanzania, he trades phrases with a lyrist named Warema Masiaga Cha Cha. The title track, which Mr. Fleck wrote in his own style, features the Malian ngoni players Bassekou Kouyate and Haruna Samake.