UI Libraries: How to Choose, Customize, and Migrate (2025)

UI libraries accelerate delivery—if you pick the right level of abstraction and treat them like infrastructure. This guide helps you evaluate, customize, and migrate with minimal disruption.

Also read: Web Design Best Practices · Web Application Design · UI Animation

Headless vs. Styled vs. Hybrids

Pick based on brand control needs, team skill, and time-to-market.

Evaluation Criteria (deep cut)

• API ergonomics: props that map to intention, not paint.
• A11y: keyboard order, focus traps, screen reader naming.
• Theming: tokens for color/space/radius; dark mode support.
• Motion: sensible transitions; easy to disable for reduced motion.
• Docs & community: recency, examples, maintenance.
• Bundle impact: ESM, treeshaking, partial imports.
• Interop: Tailwind, CSS-in-JS, or vanilla CSS.

Next.js + pnpm Integration

Install

pnpm add @radix-ui/react-dialog @radix-ui/react-popover @radix-ui/react-tooltip
# or
pnpm add @mui/material @emotion/react @emotion/styled
# or
pnpm dlx shadcn@latest init && pnpm dlx shadcn add button card dialog

Optimize imports

// next.config.mjs
export default { experimental: { optimizePackageImports: ["lucide-react"] } };

MUI theme override

// app/theme.tsx
"use client";
import { ThemeProvider, createTheme } from "@mui/material/styles";
 
const theme = createTheme({
  palette: { mode: "light", primary: { main: "#111827" } },
  shape: { borderRadius: 8 },
  typography: { button: { textTransform: "none" } },
});
 
export function MuiThemeProvider({ children }: { children: React.ReactNode }) {
  return <ThemeProvider theme={theme}>{children}</ThemeProvider>;
}

Radix + Tailwind (Dialog)

import * as Dialog from "@radix-ui/react-dialog";
 
export function Confirm({ open, onOpenChange, onConfirm }) {
  return (
    <Dialog.Root open={open} onOpenChange={onOpenChange}>
      <Dialog.Trigger className="btn">Delete</Dialog.Trigger>
      <Dialog.Content className="rounded-xl bg-white p-6 shadow-xl">
        <Dialog.Title>Confirm deletion</Dialog.Title>
        <div className="mt-4 flex gap-3">
          <button className="btn-primary" onClick={onConfirm}>
            Yes
          </button>
          <Dialog.Close className="btn">Cancel</Dialog.Close>
        </div>
      </Dialog.Content>
    </Dialog.Root>
  );
}

Customization Strategy

1. Define tokens first (color, space, radius, shadows, motion).
2. Theming pass (global), then component-level overrides.
3. Create a “playground” route to audition states (hover, focus, error).
4. Build compound components for repeated patterns (FilterBar, Toolbar).

Migration Without a Rewrite

• Strangle pattern: wrap old components with adapters; swap incrementally.
• Route-by-route replacement; keep styles side-by-side temporarily.
• Snapshot test visual regressions; lock down critical flows with e2e.
• Document mapping: Old → New components; agree on “good enough.”

Pitfalls to Avoid

• Mixing multiple heavy kits on one surface.
• Overriding styles via specificity wars; prefer tokens/vars.
• Loading entire icon packs; import per icon.
• Ignoring prefers-reduced-motion and keyboard paths.

Checklist

• Tokens set and documented
• A11y verified for key components
• Imports optimized (tree-shake friendly)
• Theming unified across routes
• Migration plan with milestones

Continue: Web Design Best Practices · Web Application Design · UI Animation