Kenan Thompson and Colin Jost talk during a Weekend Update bit on SNL. Everyone always talks about the incredible run Kenan Thompson has had on Saturday Night Live. He’s been on the show for more than two decades and is the longest tenured Not Ready For Primetime Player by a large margin, but for almost that entire stretch, Colin Jost has been right there with him. The writer, turned head writer, turned Weekend Update co-host jointed the show all the way back in 2005, just two years after Thompson.