Over the course of a few years, I've helped ArtStation establish a design system. The system was built in collaboration with internal stakeholders, developers and more importantly, the artists and studios. We included each party at every step of the way so that we could always evaluate our solutions and collect new information.
The design system had a style guide as a basis for the UI and some general UX principles that we developed as we learned how most professional artists behaved.
I was also in charge of the design of the mobile applications which are available on the App Store and the Google Play Store.
As we released Pro Plans, I was in charge of redesigning the artist's profile page.