A design system is the shared language a team speaks when it builds a product: the parts, the rules for using them and the reasons behind the rules.
Introduction
Most teams start one after the third button that looks almost, but not quite, like the other two. The cost is rarely the button; it is the conversation every time someone has to choose between them.
A system turns those conversations into decisions made once. It does not slow a team down; it removes the questions nobody needed to ask.
Software and tools
The tools matter less than the habits around them. Keep the source of truth in code, describe every part where people already work, and let the build check what people forget.
- Name the parts the way the team already talks about them.
- Write down when to use each one, and when not to.
- Fail the build when a colour pair misses contrast.
“We stopped arguing about buttons and started arguing about the product. That was the point.”
Ada Lovelace, Design Lead
Other resources
Read the parts' own documentation first: every variant, every state, and the keyboard behaviour you get for free.
Conclusion
Start small: one page built entirely from shared parts teaches more than any audit. Grow the system where the product needs it, not ahead of it.