Building Inertia-UI

Design systems are more than just a collection of UI components. They are the language through which a product communicates with its users.

In this post, I want to share some insights from building Inertia-UI, a library focused on performance, accessibility, and developer experience.

Why Another UI Library?

While there are many excellent libraries like Shadcn or Radix, I feel there is room for something that prioritizes:

• Motion by default: Integrating Framer Motion deeply into the core.
• Zero-config performance: Optimized bundles and runtime.
• Extreme customizability: Using OKLCH colors and modern CSS.

The Technical Challenges

One of the biggest hurdles is ensuring that complex animations don't impact the core interaction loops. When you introduce physics-based animations to fundamental building blocks like buttons or inputs, performance regressions can easily slip in.

We are solving this by leveraging Framer Motion's hardware-accelerated animations and ensuring that layout shifts are strictly minimized.

Embracing OKLCH Colors

A significant design decision is adopting OKLCH color spaces. Unlike HSL or RGB, OKLCH provides perceptually uniform lightness. This means that a blue and a yellow with the same lightness value in OKLCH will actually appear equally bright to the human eye.

This allows us to programmatically generate accessible color palettes with perfect contrast ratios, eliminating the guesswork from theme creation.

Building for the Future

Inertia-UI isn't just about what looks good today; it's about building a scalable foundation. By relying heavily on CSS variables and a rigid design token structure, adopting dark mode or entirely custom brand themes becomes a trivial task of overriding a few root variables.

What's Next?

We are currently refining the API surface of our more complex components, such as data tables and command palettes, ensuring they remain fully accessible (WAI-ARIA compliant) without sacrificing the fluid motion that defines Inertia.

Stay tuned for more updates as we approach the beta release! I'll be sharing deep dives into specific component architectures in the coming weeks.