Affected version
Reports that share this version, grouped in one feed.
Turbopack dev server consumes ~16 MB × number of previously compiled pages for each subsequent route handler compilation. Ordering matters: requesting handlers before pages avoids the blow-up. Regression introduced in 16.3.0-canary.101.
Next.js 16.3.5 production build using Turbopack panics with a TurbopackInternalError: 'expected chunkable module for async reference' when the bknd package is used. The webpack build succeeds, indicating a Turbopack-specific issue with async module chunking.
In Next.js 16.3.x with output: 'standalone', next-i18next.config.js is not copied into .next/standalone, causing 500 errors because next-i18next cannot locate its config at runtime. Regression from 16.2.12.
When using cacheComponents and partialPrefetching with a custom incremental cache that starts empty, the first request to a statically generated dynamic route (e.g., /en) results in HTTP 500 due to a NEXT_STATIC_GEN_BAILOUT error when Next.js attempts to render the fallback shell dynamically.
In Next.js 16 with Turbopack, when a `next/dynamic` component is nested inside another `next/dynamic` component (both with `ssr: true` and CSS imports), the server-rendered HTML omits the `<link rel="stylesheet">` for the deeper component's CSS. This causes a flash of unstyled content (FOUC) and significant layout shift (CLS 0.4157) in production on slow connections. The issue is a regression introduced in 16.1.0 and persists through 16.4.0-canary.34. Webpack builds do not exhibit the problem.
Next.js 16.3.5 with reactCompiler and experimental.turbopackRustReactCompiler throws a runtime ReferenceError (Cannot access 'parseItem' before initialization) because React Compiler lowers hoisted function declarations to const bindings while leaving lazy useState initializers above them, breaking valid JavaScript hoisting.
When a request receives a stale cached entry from a "use cache" function, the background revalidation incorrectly replaces the saved entry in the Resume Data Cache with the pending result of the regeneration. This leads to dev-time "uncached data" errors on validation renders and in production to runtime prefetch/RSC responses missing or mixing cache versions when using cacheComponents and partialPrefetching.
Setting `"type": "commonjs"` in a Next.js project using Turbopack causes build and dev failures because Turbopack enforces the declared module format on App Router source files (which are written as ESM) and on generated `.next-internal` server-action entries, even though Webpack ignores this field. The issue affects all App Router files and internal virtual modules, not just the `'use client'` proxy previously fixed.
With partialPrefetching enabled, dynamic pages are rendered four times per request (request, runtime prefetch, shell upgrade x2). Timers scheduled during each render capture AsyncLocalStorage context and retain large React Flight request and cache state, causing memory retention of ~3.8 MiB per request for a 10-minute timer, up to 45 GiB at 20 rps.
Next.js 16.3 introduced a regression where route handler modules are not eagerly evaluated at startup, causing the first request to a route handler to pay full module evaluation cost. This increases cold start latency and p99 for deployments.
In Next.js 16.3.5 with Turbopack, the web worker bootstrap parses its configuration from the URL hash. In-app browsers like Facebook/Instagram append query parameters (e.g. ?fbclid=abc) after the fragment, making the hash value invalid JSON and causing JSON.parse to throw, preventing worker startup.
On the WASM SWC bindings, codeFrameColumns deserializes options directly into a strict CodeFrameOptions struct that cannot accept boolean color or undefined maxWidth, unlike the native N-API binding. This causes 100% of code frames to fail on the WASM fallback, replacing the actual error with a serialization error in the dev overlay, server console, and build diagnostics.
sitemap.ts (and robots.ts) that export `revalidate` are incorrectly classified as STATIC_FILE in the adapter build output, losing their revalidate value and causing stale content on Vercel. The route is never regenerated and no function is emitted.
When a navigation clicks a Link during an in-flight prefetch, a pending segment-cache entry is passed to React as a plain promise. In partial or rejected prefetches the promise resolves to null, causing React to commit an empty segment and drop the document title.
When a modal is opened via interception over a page that is itself interceptable, performing a router.refresh() or revalidatePath causes the background route refresh request to incorrectly include the Next-Url header, leading to an intercepted response and an MPA fallback, resulting in a full page load and loss of client state.
In Next.js production builds (App Router), router.refresh() fails to trigger a server round-trip when the current page was streamed and the URL contains a query string. This causes stale UI after mutations on filtered list pages, with no fetch initiated. The issue is present across multiple versions, with 16.2.12 only affected for query-string URLs, and 16.3.5+ affected for all streamed pages. A fix requires forcing cache invalidation for the current URL during refresh.
File-system-cache `set()` omits the `.rsc` file for PPR routes, causing `get()` to treat the entry as missing after restart or eviction. This results in fallback shell re-rendering and stale RSC payloads for client navigation, leading to data inconsistency.
During background revalidation of partially prerendered (PPR) routes, Next.js reads the Link header from the already-finished response object instead of from the values React passed to appendHeader, causing Flight-triggered regenerations to store no Link header and lose font preload hints.
In Next.js 16.3.5-16.4.0-canary.32, a redirect() inside a Suspense boundary in a layout triggers an instant navigation validation error on every warm request, although redirect is intentional control flow. This suppresses genuine blocking-prerender-dynamic findings on the same route.
In Next.js development mode, soft navigation to a route whose server component redirects after async work triggers an uncaught TypeError because React Server Components client code calls performance.measure with a negative end timestamp.
In App Router-only builds, requesting a dynamic route with a malformed percent-encoded segment (e.g. /items/%E0%A4) triggers a DecodeError during route matching. Base-server attempts to render the Pages Router /_error page with a 400 status, but that page does not exist in builds without any Pages Router routes, resulting in a bare 500 response.
In Next.js dev with Turbopack, editing a file after client-side navigation does not trigger hot module replacement until a manual page reload. The HMR subscription for the new route is not registered after client navigation.
Next.js 16.x with Turbopack and pnpm emits a false 'Module not found' warning for styled-jsx/style.js during Pages Router builds, even though the build succeeds and the file is traced.
Using styled-jsx in a Pages Router application with pnpm triggers a false 'Module not found' warning during Turbopack builds. The warning occurs because Turbopack's external tracing attempts to resolve styled-jsx/style.js from the project root, but pnpm's strict node_modules layout does not hoist styled-jsx to the root. The build still succeeds and the file is correctly traced via Next.js's own require hooks.