PacketFabric network-as-a-service company announces Vincent English, ex-Megaport, as CEO … Sigmoid data engineering and AI consulting firm appoints Shankar Viswanathan, ex-Procter & Gamble, chief commercial officer ... Spectrotel, communication services provider, names Observe.ai’s Robert Fish, also ex-Intelisys, vice president-south region channel sales ... Riedel Communications names European Media Group’s Lucy O’Brien director-customer success, Europe, the Middle East and Africa ... Truecaller, global communications platform, names MetaMap’s Ogochukwu Onwuzurike country manager-Nigeria, and Uber’s Nicolas Vargas country manager-Colombia.