I really like this post by Brad Frost about what is and isn’t a design system, particularly when he de-emphasizes the importance of tools when it comes to that sort of work :
...components living inside static design tools like Sketch isn’t itself a design system. Pardon my clickbait. Perhaps a better title would have been “Your Sketch library is not a(n entire) design system.”
No doubt tools like Sketch are super valuable, and having a set of reusable components inside them helps design teams establish thoughtful and consistent UIs. However, a Sketch library is just one piece of the design system puzzle. A design system also can include other puzzle pieces like:
Coded UI components
Component guidelines, usage, and details
Voice and tone guidelines
Resources (internal and external)
I’ve been mulling this post over the past couple of days and I’ve started to think of design systems as much more than a suite of tools. In fact, I’m starting to think that folks who work on design systems should start to de-emphasize how important specific tools are and focus much more on the community-building aspects of the work instead.