Paizo wants to bring some more class to Starfinder. Specifically, the Evolutionist class. And they know that all the internal playtesting they can do doesn't hold a candle to hundreds or thousands of eyes on the material. And so they've got their public playtest going on for the new material. You can sign up for it now.
From the article:
The evolutionist is a new class for Starfinder that brings to bear the power of transformation over time. As an evolutionist, you’ll become a fantastical extraplanar being, turn from mere mortal into machine, accept the powers and perils of undeath, or erupt with chimeric potential and vital energy. Whichever path you choose, you’ll have to balance your burgeoning capacity for change with the sometimes-dangerous effects of tapping into such potential.
This playtest is your chance to get a look at an early version of this new class and have a hand in its development before it hits shelves in an upcoming book!