Source: https://seerepo.com/compare/resend/react-email/vs/shadcn-ui/ui
Markdown source: https://seerepo.com/compare/resend/react-email/vs/shadcn-ui/ui.md
Description: react-email and ui share 11 technologies: Next.js, React, Tailwind CSS, PostCSS, Radix UI, sonner, vaul, Lucide, Zod, ora, and prompts. Both are written in TypeScript.

# react-email vs ui

react-email and ui share 11 technologies: Next.js, React, Tailwind CSS, PostCSS, Radix UI, sonner, vaul, Lucide, Zod, ora, and prompts. Both are written in TypeScript.

- [resend/react-email](https://seerepo.com/r/resend/react-email): 💌 Build and send emails using React
- [shadcn-ui/ui](https://seerepo.com/r/shadcn-ui/ui): Composable, accessible components with thoughtful defaults. Build your own component library with code you can customize, extend, and make your own.

## What they share and what sets them apart

- In common: Next.js, React, Tailwind CSS, PostCSS, Radix UI, sonner, vaul, Lucide, Zod, ora, prompts
- Only in react-email: Redis, Resend, classnames, tiptap, Framer, react-three, three, prism-react-renderer, vercel, @floating-ui/react-dom, hast-util-from-html, prismjs, picospinner, marked, html-to-text, entities, html5parser, tailwind-merge, @lottiefiles/dotlottie-react, node-html-parser
- Only in ui: lru-cache, Vercel, MCP, React Router, Vite, TanStack, cn, class-variance-authority, next-themes, recharts, Base UI, react-resizable-panels, embla-carousel-react, react-day-picker, cmdk, dnd-kit, motion, React Hook Form, hugeicons, @tabler/icons-react, @phosphor-icons/react, @remixicon/react, ai, @ai-sdk/react, shiki, streamdown, unist-util-visit, tailwindcss-animate, geist

## Side by side

| | react-email | ui |
|---|---|---|
| Size | 209,349 lines written, 931 code files | 636,496 lines written, 3,892 code files |
| Who writes it | 3.3% of its commits signed by AI. With Cursor, Claude Code, and GitHub Copilot | 3% of its commits signed by AI. With Claude Code, Cursor, GitHub Copilot, Codex, and Devin |
| Activity | Last push November 5, 2026, 2,625 commits, 19,913 stars | Last push November 4, 2026, 2,298 commits, 127,326 stars |
| Tests | 194 test files. 18.3% of its code files have a test that imports them | 415 test files. 3.8% of its code files have a test that imports them |

- Size: Lines written by people and agents, without generated ones; code files, without tests.
- Who writes it: A commit counts as AI's when it carries its signature: a Co-Authored-By line, its author name or the merge of its branch.
- Activity: From GitHub and its history, on the day SeeRepo read it.
- Tests: The files that test the code, and the share of code files a test imports.

## Frequently asked questions

### Which is bigger, react-email or ui?

ui, with 636,496 lines written; react-email has 209,349.

The proof: [shadcn-ui/ui's code at commit 8a35366](https://github.com/shadcn-ui/ui/tree/8a3536678a528cc012b9e62484290e79d0be410f)

### Which has more GitHub stars, react-email or ui?

ui, with 127,326 stars; react-email has 19,913.

The proof: [shadcn-ui/ui on GitHub](https://github.com/shadcn-ui/ui)

### Which has more tests, react-email or ui?

ui, with 415 test files; react-email has 194.

The proof: [shadcn-ui/ui's code at commit 8a35366](https://github.com/shadcn-ui/ui/tree/8a3536678a528cc012b9e62484290e79d0be410f)

### Which was updated more recently, react-email or ui?

react-email: its last push was on November 5, 2026, and ui's on November 4, 2026.

The proof: [resend/react-email's commits on GitHub](https://github.com/resend/react-email/commits)

### Which has more commits signed by AI, react-email or ui?

react-email: an AI signed 3.3% of its commits, with Cursor, Claude Code, and GitHub Copilot; in ui, 3%.

The proof: [the commits each tool signed in resend/react-email](https://seerepo.com/r/resend/react-email/ai)

## Sources

- resend/react-email: Read on November 5, 2026, at commit d8a0778 (https://github.com/resend/react-email/tree/d8a077865793516917f42993a1e13becd797cad1)
- shadcn-ui/ui: Read on November 4, 2026, at commit 8a35366 (https://github.com/shadcn-ui/ui/tree/8a3536678a528cc012b9e62484290e79d0be410f)

## What is your repo built with?

Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.