Error map
Route used params.x — params should be awaited Next.js 15: Error: Route "/blog/[slug]" used `params.slug`. `params` should be awaited before using its properties
Next.js · layer 1, On your device
Centre: this error. First ring: errors it is linked with (9). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (9)
Next.js 15: Route "/x" used `cookies().get('token')`. `cookies()` should be awaited before using its value
Since Next.js 15, cookies(), headers(), params and searchParams are async — they must be awaited.
Next.js: ⨯ Conflicting app and page file was found, please remove the conflicting files to continue: "pages/index.tsx" - "app/page.tsx"
The same URL is defined in both the `app` and `pages` directories.
Browser: Access to fetch at 'https://api.example.com/api/data' from origin 'https://app.example.com' has been blocked by CORS policy (Next.js route handler)
A cross-origin request to your Next.js API route is blocked because the response lacks CORS headers.
Next.js: useSearchParams() should be wrapped in a suspense boundary at page "/". Read more: https://nextjs.org/docs/messages/missing-suspense-with-csr-bailout
A Client Component using `useSearchParams` is statically rendered, so the build needs a Suspense boundary for the client-only par…
Next.js 15: Route "/search" used `searchParams.q`. `searchParams` should be awaited
Page props `searchParams` are a Promise in Next.js 15 and must be awaited.
Next.js: Failed to compile. ./src/app/page.tsx:15:9 Type error: Type 'string | undefined' is not assignable to type 'string'
TypeScript type checking failed during `next build`, which blocks the deployment.
Next.js: FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory (during next build)
Node ran out of memory while building a large Next.js app (or on a small CI/Vercel runner).
Next.js: Error occurred prerendering page "/blog" TypeError: fetch failed { cause: Error: connect ECONNREFUSED 127.0.0.1:3000 }
During `next build` a page tried to fetch data from a server (often your own app or an API) that isn't running yet.
Next.js: Error: You cannot use different slug names for the same dynamic path ('id' !== 'slug')
Sibling dynamic folders at the same level use different parameter names.
Two steps away (24)
Authentication plugin 'caching_sha2_password' cannot be loaded
An old MySQL client/driver can’t use MySQL 8’s default authentication plugin.
npm WARN old lockfile — The package-lock.json file was created with an old version of npm, so supplemental metadata must be fetched
The lockfile is lockfileVersion 1 (npm 6) and npm 7+ is upgrading it.
npm ERR! cb() never called!
An old npm crash during install — usually network/cache corruption.
TypeError: Missing parameter name at 1 (path-to-regexp)
An Express 5 (path-to-regexp v8) route uses old wildcard syntax like '*' or '/:id?'.
No routes matched location "/x"
React Router found no route definition for the current URL.
Error occurred prerendering page "/x". Read more: https://nextjs.org/docs/messages/prerender-error
A page threw an error while Next.js was rendering it at build time.
Browser: Access to XMLHttpRequest at 'https://api.example.com' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header — Laravel
The browser blocked a cross-origin call to your Laravel API because the response lacks the right CORS headers.
Next.js: Warning: validateDOMNesting(...): <div> cannot appear as a descendant of <p> / In HTML, <p> cannot be a descendant of <p>. This will cause a hydration error
The rendered HTML has an invalid element nesting, so the browser "fixes" it and React's hydration no longer matches.
Next.js: You're importing a component that needs createContext. It only works in a Client Component but none of its parents are marked with "use client"
A context provider (or a lib that uses `createContext`) is used in a Server Component.
Error: A component suspended while responding to synchronous input.
A component suspended (lazy load or data fetch) during an update that wasn’t wrapped in a transition, and there is no Suspense bo…
Error: Dynamic server usage: Route /x couldn't be rendered statically because it used `cookies`
Next.js tried to statically render a route that reads request-specific data (cookies, headers, searchParams).
Next.js: Page "/blog/[slug]" is missing "generateStaticParams()" so it cannot be used with "output: export" config
A dynamic route can't be statically exported without telling Next.js which paths to generate.
TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts"
Node tried to run a TypeScript file as ESM without a TypeScript loader.
TS2307: Cannot find module 'x' or its corresponding type declarations.
TypeScript can’t resolve the import — the package isn’t installed, the path alias isn’t configured, or there are no types.
TS7016: Could not find a declaration file for module 'x'. 'x.js' implicitly has an 'any' type.
The JavaScript package has no TypeScript types bundled and no @types package installed.
npm ERR! code ELIFECYCLE / Command failed with exit code 1
An npm script (build, start, test, postinstall) exited with an error. ELIFECYCLE is only the wrapper — the real error is printed…
gyp ERR! build error / node-gyp rebuild failed
A dependency with native C/C++ code couldn’t compile — missing build tools, Python, or an unsupported Node version.
FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory
The V8 heap hit its limit — a large build (webpack, tsc, Next.js) needs more memory, or the app leaks.
Error: error:0308010C:digital envelope routines::unsupported
An old build tool (webpack 4, old react-scripts) uses a hash algorithm that OpenSSL 3 in Node 17+ disables.
Error: @prisma/client did not initialize yet. Please run "prisma generate"
The generated Prisma Client is missing or out of date.
Error: Node Sass does not yet support your current environment
node-sass (deprecated) has no binary for your Node version/OS.
Error: NextRouter was not mounted.
next/router’s useRouter was used inside the App Router (app/ directory), which uses next/navigation instead.
Vue Router: [Vue Router warn]: No match found for location with path "/users/42"
The router has no route record matching that path (typo, missing route, or case/base issue).
Nuxt: 404 Page not found: /blog/my-post / [Vue Router warn]: No match found for location with path
Nuxt's file-based router has no page matching the URL (wrong file/folder names or missing param syntax).
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