How I Built a Reusable Component Library from Scratch
A practical guide to creating a shared, type-safe component library, from initial audit to publishing, and the lessons learned along the way.
Rong Yuthean
After years of copying the same components between projects, I finally built a proper shared component library. The process was challenging but incredibly rewarding, and I want to share my approach for other engineers considering the same journey.
I started by auditing five of our applications, looking for duplicated components and patterns. The results were eye-opening: seven slightly different button implementations, three date pickers, and inconsistent handling of loading and error states.
Rather than designing everything upfront, I built the library iteratively alongside a real product. Each component was extracted only once it had proven itself in production code.
The core of the library includes:
- Strongly typed components with TypeScript props and emitted events
- Design tokens exposed as CSS variables for theming
- Accessibility built in, with keyboard navigation and ARIA attributes tested automatically
- Visual regression tests and auto-generated documentation
The biggest challenge wasn't technical but organizational: getting teams to trust and adopt a shared dependency. Semantic versioning, clear changelogs, and codemods for breaking changes made upgrades painless.
The payoff has been enormous: new features ship roughly 40% faster, UI bugs have dropped significantly, and every app now looks and behaves consistently.
If you're considering building your own library, start small with your most-used components, test them in real products, and automate everything you can. A good component library should feel like a trusted teammate, not a set of restrictions.