Component Library

The Situation

A fast-growing SaaS company had accumulated 3 years of design and engineering debt. Five product squads were independently creating UI components, resulting in 14 different button variants, 6 modal implementations, and zero shared conventions.

Audit

We catalogued every unique component across the product surface. The numbers were stark:

Total CSS payload dropped from 847KB to 124KB after consolidation.

Token Architecture

We built a three-tier token system:

Tier 1 — Primitives

Raw values with no semantic meaning: blue-500, space-16, radius-md. These never appear in component code directly.

Tier 2 — Semantic

Purpose-driven aliases: color-action-primary, space-inline-md, radius-interactive. These are what components consume.

Tier 3 — Component

Scoped overrides for specific contexts: button-padding-x, input-border-color. Used sparingly to handle edge cases.

Component Playground

Below is a live example of a draggable layout widget — one of the interactive primitives we built for the documentation site’s playground:

Component API Design

Every component follows strict conventions:

• Composition over configuration — prefer children and slots over boolean props
• Polymorphic as prop — any component can render as any HTML element
• Controlled by default — state is always lifted unless explicitly opted out

Version Tracking

We shipped 47 minor versions and 3 major versions in the first year. The counter below demonstrates the kind of interactive documentation element we built to track component usage:

Adoption

Rather than a “big bang” migration, we introduced the system incrementally:

1. Week 1–4: New features must use the system
2. Week 5–12: Each sprint includes 2 hours of migration work
3. Week 13+: Legacy components sunset as pages are touched

After 6 months, 94% of the product surface used the shared system.

This is a template case study. Replace with your actual project work.