Source: https://seerepo.com/r/vercel/next.js/built Markdown source: https://seerepo.com/r/vercel/next.js/built.md Description: next.js is a JavaScript repo built with React, Express, Tokio, scheduler, Next.js, and 1 more. It stores its data in concurrent-queue. # What is next.js built with? next.js is a JavaScript repo built with React, Express, Tokio, scheduler, Next.js, and 1 more. It stores its data in concurrent-queue, makes its content with Cheerio, js-yaml, image, and sharp, validates its data with prop-types and Ajv, is tested with libfuzzer-sys, playwright, Testing Library, Jest, @playwright/test, and 1 more, and deploys with tracing, tracing-subscriber, OpenTelemetry, and pino. It has 5,697 files and 2,391,614 written lines, with 18,587 test files. Read on November 4, 2026, at commit 97f1a2c. Repository: https://github.com/vercel/next.js ## Frontend (/) ### The base - **[React](https://seerepo.com/uses/react)**: 2 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ### Styles - **styled-jsx**: 7 files - **emotion**: 5 files - **[Tailwind CSS](https://seerepo.com/uses/tailwind-css)**: 4 files - **PostCSS**: 3 files - **geist**: 1 file ### Interface - **MUI**: 9 files - **react-virtualized**: 2 files - **Framer**: 1 file - **Headless UI**: 1 file ### Icons - **@heroicons/react**: 3 files - **[Lucide](https://seerepo.com/uses/lucide)**: 2 files ## Backend (/) ### The base - **[Express](https://seerepo.com/uses/express)**: 1 file ### Data - **concurrent-queue**: 3 files ## Support (/) ### The base - **[Tokio](https://seerepo.com/uses/tokio)**: 77 files - **scheduler**: 1 file ### Content - **Cheerio**: 135 files - **js-yaml**: 4 files - **image**: 1 file - **sharp**: 1 file ### Validation - **prop-types**: 2 files - **[Ajv](https://seerepo.com/uses/ajv)**: 1 file ### Testing - **libfuzzer-sys** - **playwright**: 92 files - **Testing Library**: 8 files - **Jest**: 2 files ### Deploy - **tracing**: 114 files - **tracing-subscriber**: 7 files - **OpenTelemetry**: 1 file - **pino**: 1 file ### Tools - **ESLint**: 22 files - **syn**: 22 files - **quote**: 20 files - **napi-derive**: 18 files - **proc-macro2**: 16 files - **get-port**: 11 files - **clap**: 10 files - **expect-type**: 5 files - **dhat**: 2 files - **SWC**: 2 files - **Prettier**: 1 file - **resolve-from**: 1 file - **tsx**: 1 file - **yargs**: 1 file ### Other - **getrandom** - **walkdir** - **anyhow**: 530 files - **bincode**: 192 files - **rustc-hash**: 147 files - **serde**: 118 files - **serde_json**: 94 files - **async-trait**: 83 files - **fs-extra**: 70 files - **smallvec**: 58 files - **regex**: 41 files - **either**: 39 files - **parking_lot**: 32 files - **futures**: 28 files - **indexmap**: 24 files - **execa**: 21 files - **tempfile**: 16 files - **escape-string-regexp**: 15 files - **thread_local**: 12 files - **urlencoding**: 12 files - **http-proxy**: 11 files - **postcard**: 10 files - **hashbrown**: 9 files - **itertools**: 9 files - **rand**: 9 files - **memmap2**: 8 files - **byteorder**: 7 files - **bytes**: 6 files - **data-encoding**: 6 files - **flate2**: 6 files - **Hyper**: 6 files - **zstd**: 6 files - **libc**: 5 files - **napi**: 5 files - **url**: 5 files - **windows-sys**: 5 files - **base64**: 4 files - **futures-util**: 4 files - **num-bigint**: 4 files - **pathdiff**: 4 files - **phf**: 4 files - **sha2**: 4 files - **thiserror**: 4 files - **Lodash**: 3 files - **rayon**: 3 files - **include_dir**: 2 files - **jiff**: 2 files - **js-sys**: 2 files - **memchr**: 2 files - **notify**: 2 files - **num-traits**: 2 files - **percent-encoding**: 2 files - **SWR**: 2 files - **tokio-util**: 2 files - **wasm-bindgen**: 2 files - **wasm-bindgen-futures**: 2 files - **.ENV**: 1 file - **arrayvec**: 1 file - **bitflags**: 1 file - **chrono**: 1 file - **console_error_panic_hook**: 1 file - **crc32fast**: 1 file - **crossbeam-channel**: 1 file - **hex**: 1 file - **minimatch**: 1 file - **moment**: 1 file - **nix**: 1 file - **num_cpus**: 1 file - **regex-automata**: 1 file - **reqwest**: 1 file - **rustls**: 1 file - **same-file**: 1 file - **sha1**: 1 file - **Socket.io**: 1 file - **socket.io-client**: 1 file - **socket2**: 1 file - **terminal_size**: 1 file - **undici**: 1 file - **unicode-width**: 1 file - **uuid**: 1 file - **webbrowser**: 1 file - **whatwg-fetch**: 1 file ## Frontend (apps/bundle-analyzer) ### The base - **[Next.js](https://seerepo.com/uses/nextjs)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) - **[React](https://seerepo.com/uses/react)**: 25 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ### Styles - **[Tailwind CSS](https://seerepo.com/uses/tailwind-css)** - **[class-variance-authority](https://seerepo.com/uses/class-variance-authority)**: 2 files - **next-themes**: 2 files - **[tailwind-merge](https://seerepo.com/uses/tailwind-merge)**: 1 file ### Interface - **[Radix UI](https://seerepo.com/uses/radix-ui)**: 6 files - **[cmdk](https://seerepo.com/uses/cmdk)**: 1 file ### Icons - **[Lucide](https://seerepo.com/uses/lucide)**: 12 files ## Support (apps/bundle-analyzer) ### Other - **clsx**: 2 files - **SWR**: 2 files ## Frontend (packages/create-next-app) ### Interface - **prompts**: 1 file ## Support (packages/create-next-app) ### Tools - **fast-glob**: 2 files ### Other - **picocolors**: 5 files ## Support (packages/devlow-bench) ### Tools - **Inquirer**: 1 file ### Other - **picocolors**: 3 files - **minimist**: 1 file - **split2**: 1 file - **url**: 1 file ## Support (packages/eslint-config-next) ### Tools - **ESLint**: 5 files - **typescript-eslint**: 2 files - **eslint-plugin-import**: 1 file - **eslint-plugin-jsx-a11y**: 1 file - **eslint-plugin-react**: 1 file - **eslint-plugin-react-hooks**: 1 file - **globals**: 1 file ## Support (packages/eslint-plugin-internal) ### Tools - **@typescript-eslint/parser**: 1 file - **ESLint**: 1 file ## Support (packages/eslint-plugin-next) ### Tools - **ESLint**: 5 files - **fast-glob**: 1 file ## Frontend (packages/next-codemod) ### The base - **[React](https://seerepo.com/uses/react)**: 37 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Support (packages/next-codemod) ### Content - **Cheerio**: 1 file ### Other - **execa**: 3 files - **picocolors**: 3 files ## Frontend (packages/next-codemod/bin/__testfixtures__/react-18-installed-mixed-router) ### The base - **[Next.js](https://seerepo.com/uses/nextjs)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) - **[React](https://seerepo.com/uses/react)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Frontend (packages/next-codemod/bin/__testfixtures__/react-18-installed-pure-pages-router) ### The base - **[Next.js](https://seerepo.com/uses/nextjs)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) - **[React](https://seerepo.com/uses/react)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Frontend (packages/next-codemod/bin/__testfixtures__/react-19-installed-mixed-router) ### The base - **[Next.js](https://seerepo.com/uses/nextjs)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) - **[React](https://seerepo.com/uses/react)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Frontend (packages/next-codemod/bin/__testfixtures__/react-19-installed-pure-pages-router) ### The base - **[Next.js](https://seerepo.com/uses/nextjs)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) - **[React](https://seerepo.com/uses/react)**: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Support (packages/next-env) ### Tools - **dotenv-expand**: 1 file ### Other - **.ENV**: 1 file ## Support (packages/next-mdx) ### Tools - **@mdx-js/loader**: 1 file ## Support (packages/next-playwright) ### Testing - **@playwright/test**: 1 file ## Support (packages/next-polyfill-nomodule) ### Other - **core-js**: 1 file - **object-assign**: 1 file - **whatwg-fetch**: 1 file ## Support (packages/next-swc) ### Other - **url**: 1 file ## Frontend (packages/next) ### The base - **[React](https://seerepo.com/uses/react)**: 189 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ### Styles - **PostCSS**: 2 files - **styled-jsx**: 2 files ## Support (packages/next) ### The base - **react-server-dom-webpack**: 18 files ### Content - **sharp**: 1 file ### Testing - **@playwright/test**: 7 files - **Testing Library**: 2 files - **msw**: 1 file ### Tools - **Babel**: 2 files - **resolve-from**: 1 file - **SWC**: 1 file ### Other - **url**: 23 files - **execa**: 1 file ## Support (packages/next/src/compiled/@edge-runtime/primitives) ### Other - **url**: 2 files ## Support (packages/next/src/compiled/@mswjs/interceptors/ClientRequest) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/@vercel/nft) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/@vercel/og) ### Content - **sharp**: 1 file ### Other - **url**: 1 file ## Support (packages/next/src/compiled/@vercel/routing-utils) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/babel-packages) ### Other - **core-js**: 1 file ## Support (packages/next/src/compiled/babel) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/edge-runtime) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/http-proxy-agent) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/https-browserify) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/https-proxy-agent) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/loader-runner) ### Other - **url**: 1 file ## Frontend (packages/next/src/compiled/postcss-flexbugs-fixes) ### Styles - **PostCSS**: 1 file ## Frontend (packages/next/src/compiled/postcss-preset-env) ### Styles - **PostCSS**: 1 file ## Support (packages/next/src/compiled/postcss-preset-env) ### Other - **url**: 1 file ## Frontend (packages/next/src/compiled/postcss-safe-parser) ### Styles - **PostCSS**: 1 file ## Frontend (packages/next/src/compiled/postcss-scss) ### Styles - **PostCSS**: 1 file ## Frontend (packages/next/src/compiled/react-server-dom-turbopack-experimental) ### The base - **[React](https://seerepo.com/uses/react)**: 12 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Frontend (packages/next/src/compiled/react-server-dom-turbopack) ### The base - **[React](https://seerepo.com/uses/react)**: 12 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Frontend (packages/next/src/compiled/react-server-dom-webpack-experimental) ### The base - **[React](https://seerepo.com/uses/react)**: 12 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Support (packages/next/src/compiled/react-server-dom-webpack-experimental) ### The base - **react-server-dom-webpack**: 1 file ### Tools - **acorn-loose**: 2 files ### Other - **url**: 2 files ## Frontend (packages/next/src/compiled/react-server-dom-webpack) ### The base - **[React](https://seerepo.com/uses/react)**: 12 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Support (packages/next/src/compiled/react-server-dom-webpack) ### The base - **react-server-dom-webpack**: 1 file ### Tools - **acorn-loose**: 2 files ### Other - **url**: 2 files ## Frontend (packages/next/src/compiled/sass-loader) ### Styles - **Sass**: 1 file ## Support (packages/next/src/compiled/sass-loader) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/serve-handler) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/source-map08) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/stream-http) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/webpack) ### Other - **url**: 1 file ## Support (packages/next/src/compiled/ws) ### Other - **url**: 1 file ## Support (packages/react-refresh-utils) ### Tools - **react-refresh**: 4 files ## Frontend (packages/third-parties) ### The base - **[React](https://seerepo.com/uses/react)**: 4 files · [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ## Support (rspack/crates/binding) ### Tools - **napi-derive**: 1 file ### Other - **anyhow** - **napi** - **serde_json** - **rustc-hash**: 3 files - **regex**: 1 file ## Support (turbopack/crates/turbopack-ecmascript-runtime/js) ### Other - **url**: 2 files ## Frontend (turbopack/crates/turbopack-node/js) ### Styles - **PostCSS**: 1 file ## Support (turbopack/crates/turbopack-node/js) ### Other - **url**: 1 file ## Other repos with a similar stack - [paperclipai/paperclip](https://seerepo.com/r/paperclipai/paperclip/built): React, Express, Tokio, Tailwind CSS, Lucide, sharp, Ajv, pino, class-variance-authority, tailwind-merge, Radix UI, cmdk · [Compare](https://seerepo.com/compare/paperclipai/paperclip/vs/vercel/next.js) - [NousResearch/hermes-agent](https://seerepo.com/r/NousResearch/hermes-agent/built): React, Tokio, Tailwind CSS, Lucide, js-yaml, tracing, tracing-subscriber, class-variance-authority, tailwind-merge, Radix UI, cmdk · [Compare](https://seerepo.com/compare/NousResearch/hermes-agent/vs/vercel/next.js) - [shadcn-ui/ui](https://seerepo.com/r/shadcn-ui/ui/built): React, Next.js, Tailwind CSS, PostCSS, geist, Lucide, class-variance-authority, next-themes, Radix UI, cmdk, prompts · [Compare](https://seerepo.com/compare/shadcn-ui/ui/vs/vercel/next.js) - [supabase/supabase](https://seerepo.com/r/supabase/supabase/built): React, Next.js, Tailwind CSS, @heroicons/react, Lucide, Cheerio, js-yaml, class-variance-authority, next-themes, Radix UI, cmdk · [Compare](https://seerepo.com/compare/supabase/supabase/vs/vercel/next.js) - [Significant-Gravitas/AutoGPT](https://seerepo.com/r/Significant-Gravitas/AutoGPT/built): React, Next.js, Tailwind CSS, geist, Framer, class-variance-authority, next-themes, tailwind-merge, Radix UI, cmdk · [Compare](https://seerepo.com/compare/Significant-Gravitas/AutoGPT/vs/vercel/next.js) - [langgenius/dify](https://seerepo.com/r/langgenius/dify/built): React, Next.js, Tailwind CSS, @heroicons/react, js-yaml, sharp, Ajv, class-variance-authority, next-themes · [Compare](https://seerepo.com/compare/langgenius/dify/vs/vercel/next.js) ## Frequently asked questions ### What language is next.js written in? next.js is written in JavaScript: 5,697 files and 2,391,614 written lines. ### What framework does next.js use? next.js is built with React, Express, Tokio, scheduler, Next.js, and react-server-dom-webpack. The proof: [in packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json](https://github.com/vercel/next.js/blob/97f1a2c8a1deb23cf03855d67f942c0fe3ded1ce/packages/next-codemod/transforms/__testfixtures__/next-lint-to-eslint-cli/flat-config-flat-compat-with-other-compat/package.json) ### What database does next.js use? next.js stores its data in concurrent-queue. ### Does next.js have tests? Yes. next.js has 18,587 test files and is tested with libfuzzer-sys, playwright, Testing Library, Jest, @playwright/test, and msw. ### Which repos have a stack like next.js's? The ones that share most of its stack: paperclipai/paperclip, NousResearch/hermes-agent, and shadcn-ui/ui. ## 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.