Williams signed a one-year, $2.5 million deal with the Cubs on Saturday, Russell Dorsey of the Chicago Sun-Times reports.
Williams was quite a useful pitcher for the Pirates in 2018, recording a 3.11 ERA in 31 starts, though that came with some mediocre peripherals and a 4.54 xFIP. He's been significantly worse over the past two years, recording a combined 5.60 ERA in 37 starts. The Cubs presumably aren't looking for Williams to do much more than compete for a spot at the back of the rotation. His main competition for that role at the moment appears to be Kohl Stewart.