v16.2.1

Note

This release is backporting bug fixes. It does not include all pending features/changes on canary.

Core Changes

• docs: post release amends (#91715)
• docs: fix broken Activity Patterns demo link in preserving UI state guide (#91698)
• Fix adapter outputs for dynamic metadata routes (#91680)
• Turbopack: fix webpack loader runner layer (#91727)
• Fix server actions in standalone mode with cacheComponents (#91711)
• turbo-persistence: remove Unmergeable mmap advice (#91713)
• Fix layout segment optimization: move app-page imports to server-utility transition (#91701)
• Turbopack: lazy require metadata and handle TLA (#91705)
• [turbopack] Respect {eval:true} in worker_threads constructors (#91666)

Credits

Huge thanks to @icyJoseph, @abhishekmardiya, @ijjk, @mischnic, @unstubbable, @sokra, and @lukesandberg for helping!

v16.2.1-canary.4

Core Changes

• Fix adapter outputs for dynamic metadata routes: #91680

Misc Changes

• Turbopack: fix webpack loader runner layer: #91727
• [turbopack] Remove incorrect debug_assert in try_read_task_cell: #91699
• Add module count field to module graph tracing spans: #91697
• turbopack-cli: add --persistent-caching flag for filesystem-backed cache: #91657
• Turbopack: pull in updated vercel/nft tests: #91651
• Update Rspack development test manifest: #91695
• [test] Unflake use-node-streams-env-precedence test: #91733
• Update Rspack production test manifest: #91694
• [turbopack] Improve regressed build speed on cross-compiled MUSL: #91477

Credits

Huge thanks to @ijjk, @mischnic, @sokra, @vercel-release-bot, @unstubbable, and @mmastrac for helping!

v16.2.1-canary.3

Core Changes

• Fix layout segment optimization: move app-page imports to server-utility transition: #91701
• Fix server actions in standalone mode with cacheComponents: #91711
• Turbopack: lazy require metadata and handle TLA: #91705

Misc Changes

• [turbopack] Optimize compaction cpu usage: #91468
• [test] Unflake rendering indicator test & skip building indicator tests: #91650
• [test] Fix edge-async-local-storage deploy test timeout & race condition: #91643
• docs: fix broken Activity Patterns demo link in preserving UI state guide: #91698
• turbo-persistence: remove Unmergeable mmap advice: #91713
• turbopack: move "compact database" tracing span to backend layer: #91693
• docs: post release amends: #91715

Credits

Huge thanks to @lukesandberg, @unstubbable, @abhishekmardiya, @sokra, @icyJoseph, and @mischnic for helping!

v16.2.1-canary.2

Core Changes

• Turbopack: enable server HMR for app route handlers: #91466
• Skip loadBindings() Lightning CSS check during next start: #91538
• refactor: extract build infra and alias changes: #90422
• feat(node-streams): add config flag, define-env, and env precedence test: #90427
• Rename /_next/webpack-hmr to /_next/hmr: #91415
• ci: add node-stream test coverage workflow: #89861
• Add per-slot error attribution for instant validation using slot markers and config depth preference: #91610
• Handle encoded params further: #91627
• Fix missing route in otel spans without base-server: #91665

Misc Changes

• turbo-tasks-backend: batch find_and_schedule_dirty using for_each_task_meta: #91497
• Restructure pr-status-triage skill: merge command into skill files: #91514
• [turbopack] Use bail! instead of panic! for duplicate module ident error: #91636
• turbo-tasks-backend: batch schedule dirty tasks in aggregation_update: #91461
• Turbopack: Add importModule() support to webpack loaders: #89630
• turbo-persistence: fix mmap page alignment and improve error context in MetaFile::open_internal: #91640
• turbopack-css: demote recoverable CSS parse warnings to Warning severity: #91524
• [test] Unflake "infinite streaming fetch" test: #91645
• [test] Unflake deterministic build - changing deployment id test: #91646
• Skip CI for agent/editor config directory changes: #91622
• Update Rspack production test manifest: #91635
• [test] Increase retry timeouts for two flaky app-action tests: #91647
• Revert "ci: add node-stream test coverage workflow (#89861)"
• [test] Fix flaky url-hash tests: #91649
• Add instant validation tests for parallel slot config attribution: #91656
• [turbopack] Respect {eval:true} in worker_threads constructors: #91666

Credits

Huge thanks to @wbinnssmith, @sokra, @unstubbable, @devjiwonchoi, @timneutkens, @feedthejim, @vercel-release-bot, @gnoff, @ijjk, and @lukesandberg for helping!

v15.5.14

Note

This release is backporting bug fixes. It does not include all pending features/changes on canary.

Core Changes

• feat(next/image): add lru disk cache and images.maximumDiskCacheSize (#91660)
• Fix(pages-router): restore Content-Length and ETag for /_next/data/ JSON responses (#90304)

Credits

Huge thanks to @styfle and @lllomh for helping!

v16.2.1-canary.1

Core Changes

• Fix(pages-router): restore Content-Length and ETag for /_next/data/ JSON responses: #90304

Misc Changes

• Add .claude/skills symlink: #91616
• Update tokio from 1.43.0 to 1.47.3: #90945

Credits

Huge thanks to @lllomh, @devjiwonchoi, and @lukesandberg for helping!

v16.2.1-canary.0

Core Changes

• Update vendored lodash to 4.17.23 to fix CVE-2025-13465: #91558
• Fix invalid HTML response for route-level RSC requests in deployment adapter: #91541
• Normalize encoded dynamic placeholders in app routes: #91603

Credits

Huge thanks to @denesbeck, @ztanner, and @ijjk for helping!

v16.2.0

Tip

Check out our Next v16.2 Blog Post to learn more about this release.

Core Changes

• Upgrade React from f93b9fd4-20251217 to 65eec428-20251218: #87323
• Turbopack: Create junction points instead of symlinks on Windows: #87606
• Turbopack: Symlink handling follow-up: #87637
• Add experimental routing package for resolving adapter routes: #86404
• Ensure outputs are correct with cache components in deployment adapters: #87018
• Move off of deprecated url.parse: #87257
• [strict-route-types] Add experimental.strictRouteTypes config: #87378
• misc: fix type check log for CI envs: #87838
• fix: revalidateTag with profile should not trigger client cache invalidation: #88069
• chore: warn when running tests against stale build: #88001
• Redesign default error pages with cleaner, more user-friendly UI: #87988
• dx: avoid next-env.d.ts change in dev: #88103
• prevent browser cache from using stale RSC responses from previous builds: #86554
• [strict-route-types] Typecheck App Router page props: #87386
• [strict-route-types] Enforce common React Component return types in App Router: #87389
• [strict-route-types] Switch to satisfies when validating page and route modules: #87398
• [strict-route-types] Don't reject number in config.api.bodyParser.sizeLimit when validating route: #87633
• Revert "dx: avoid next-env.d.ts change in dev": #88153
• [strict-route-types] Typecheck pages router routes in absence of App Router: #87628
• [strict-route-types] Ensure cache profiles and routes are type-checked even if .next is excluded: #87768
• add compilation error for taint when not enabled: #88173
• feat(next/image)!: add images.maximumResponseBody config: #88183
• Add maximum size limit for postponed body parsing: #88175
• metadata: use fixed segment in dynamic routes with static metadata files: #88113
• feat: add --experimental-cpu-prof flag for dev, build, and start: #87946
• Add experimental option to use no-cache instead of no-store in dev: #88182
• fix overlay frames cannot be opened sometimes: #88210
• Handle pnpm-workspace.yaml while searching for monorepo root: #74818
• Add more debug logs to 'use cache' wrapper: #88219
• Omit unused arguments from 'use cache' function calls: #86920
• Only log pending revalidates... debug log if applicable: #88221
• fix(next/image): bump sharp@0.34.5: #88238
• Disallow javascript urls in router methods and redirects: #88185
• Fix relative same host redirects in node middleware: #88253
• Remove loadConfig from main development process, pass value from child process: #88230
• Update deploy adapters outputs and handler interfaces for node and edge: #88247
• Move Ready in time before handler initialization: #88235
• next/image: support custom cache handlers: #88248
• feat: add Claude Code plugin marketplace with Cache Components skill: #87993
• refactor: consolidate PPR into cacheComponents architecture: #88243
• Turbopack: include fewer traced files for standalone: #88322
• feat(turbopack): add resolve plugin condition variant of Always and Never: #88190
• perf: use length = 0 to clear the logging array: #88244
• Time logs: Show full millisecond instead of 1 decimal: #88313
• [turbopack] Enable inferring module side effects by default: #87216
• Track search string as part of "refresh state": #87203
• Pass RouteTree into navigation function: #87256
• Read from segment cache unknown routes: #87293
• Pass loading boundary as part of RSC data: #87825
• Revert "refactor: consolidate PPR into cacheComponents architecture (#88243)": #88421
• fix: support TypeScript noUncheckedSideEffectImports for CSS imports: #88199
• Don't import typescript at runtime: #88321
• fix: use RDC for server action requests: #88129
• Warn when overriding Cache-Control header on /_next/ routes: #88353
• [prebuilt-skew-protection] feat: adding in automatic deploymentId: #88012
• Revert "[prebuilt-skew-protection] feat: adding in automatic deploymentId": #88449
• Turbopack: Update reqwest, remove experimental system TLS feature: #88290
• Revert "prevent browser cache from using stale RSC responses from pre…: #88457
• Turbopack: retain loader tree order for metadata: #88487
• Turbopack: more dead code: #88505
• fix(build): prevent route handler manifests from inheriting unrelated client components: #88419
• Upgrade React from 65eec428-20251218 to 3e1abcc8-20260113: #88530
• Better typesafety for interopDefault: #88486
• keep next-env.d.s unchanged between dev and build: #88428
• Remove sibling caches from CacheNode tree: #87991
• Upgrade React from 3e1abcc8-20260113 to 4a3d993e-20260114: #88547
• Finish deleting Mutable from router implementation: #88046
• fetch(next/image): reduce maximumResponseBody from 300MB to 50MB: #88588
• [CC] Fix dev validation error from server action bound args: #88600
• Fix incorrect 'Ready in' time for next start: #88589
• feat: server action logging: #88277
• Log browser error and warnings in terminal: #88352
• Upgrade React from 4a3d993e-20260114 to bef88f7c-20260116: #88649
• fix: make RedirectType constant properties literal types: #88653
• Turbopack: add support for matching loaders on resource queries: #88644
• fix: capture promisified setImmediate separately: #88346
• fix: setImmediate[util.promisify.custom] access fails in edge runtime: #88685
• Fix --debug-build-paths bracket escaping for glob patterns: #88660
• Add negation pattern support to --debug-build-paths: #88654
• Only filter next config if experimental flag is enabled: #88733
• [Devtool Indicator] Fix cross alignment: #88664
• Turbopack: don't use build id for pages router client-side manifests: #88641
• Allow inspecting server with next start --inspect: #88744
• Turbopack: Add --debug-build-paths support to filter routes: #88655
• Upgrade React from bef88f7c-20260116 to 41b3e9a6-20260119: #88756
• Use rewritten pathname for implicit cache tags: #88732
• Upgrade React from 41b3e9a6-20260119 to d2908752-20260119: #88774
• Add experimental_gesturePush to App Router: #88776
• Rename rewroteURL to rewrittenPathname in request metadata: #88751
• Simplify getImplicitTags to accept pathname instead of url object: #88753
• Add NEXT_DEPLOYMENT_ID global: #86738
• Turbopack: remove deployment id suffix from client reference manifest chunks: #88741
• Inject <html data-dpl-id> and don't inline it into JS anymore: #88761
• [metadata] match the Metadata and ResolvedMetadata type: #88739
• Reuse bfcache data during Full prefetches: #88606
• Embed static sibling info in route tree: #88692
• Fix revalidatePath with params and trailing slash when deployed: #88623
• fix: preserve cache behavior for PPR fallback shells with root params: #88556
• Upgrade React from d2908752-20260119 to b546603b-20260121: #88860
• stabilize browser log forward options: #88857
• [devtools] Wrap long file names of stack frames in the error overlay: #88886
• [devtools] Fix notch coloring of error overlay in forced colors mode: #88892
• Remove deploymentId from App Router RenderOptsPartial: #88866
• feat: implement LRU cache with invocation ID scoping for minimal mode response cache: #88509
• [prebuilt-skew-protection] feat: adding in automatic deploymentId: #88496
• [devtool] Add hydration diff indicator for diff lines: #88919
• Revert "[prebuilt-skew-protection] feat: adding in automatic deploymentId": #88942
• [turbopack] add task type infromation to the print_cache_item_size feature: #88925
• Upgrade React from b546603b-20260121 to 24d8716e-20260123: #88963
• Turbopack: add ?dpl= to all asset urls returned by Turbopack: #88828
• feat(next-codemod): add agents-md command for AI coding agents: #88961
• Update font data: #88975
• Improve agents-md prompt to force doc retrieval: #88997
• [Reapply] Add useEffectEvent to disallowed React APIs in Server Components: #88985
• Apply fixes for onBuildComplete and route module: #88831
• Rename renderOpts.nextExport to isBuildTimePrerendering: #88951
• docs: fix typos in README.mds: #89022
• refactor: consume global-error from loader tree: #88437
• Fix chunk loading when using __turbopack_load_by_url__ with query: #88899
• [mcp] change the mcp endpoint response to JSON: #88911
• Reapply "[turbopack] Add bundling support for worker_threads" (#88725): #88967
• fix: ensure LRU cache items have minimum size of 1 to prevent unbounded growth: #89040
• Upgrade React from 24d8716e-20260123 to 8c34556c-20260126: #89066
• Use null-prototype objects in server actions manifests: #89069
• Re-enable types-and-precompiled: #89070
• Apply segment changes to adapters outputs: #89072
• Improve no response route handler error: #89036
• Limit number of server action arguments to 1000: #89068
• [prebuilt-skew-protection] feat: adding in automatic deploymentId: #88958
• Decouple route stale time from segment-level data: #88834
• Decouple route and segment cache lifecycles: #88989
• [ci] Silence baseline-browser-mapping warnings: #89175
• [Cache Components] Prevent streaming fetch calls from hanging in dev: #89171
• React types update: #89110
• [nextjs] feat: removing length requirement: #89173
• add GPTBot to matcher for known bots: #89188
• Ensure .md licenses are included in vendored packages: #89201
• Switch development log item format as JSON: #89168
• IsolatedDevBuild flag removal: #89167
• fix: coerce HEAD to GET for internal images: #84180
• Upgrade React from 10680271-20260126 to 230772f9-20260128: #89250
• Upgrade tar used to extract SWC binary : #89158
• Sort prerender manifest routes: #89246
• Track vary params for segments without server-side param access: #88998
• Optimistic routing: client-side route prediction: #88965
• Keep pages/404.js to be able to dynamically render it anyway: #89263
• fix: fully static pages should e...

v16.2.0-canary.104

Core Changes

• Turbopack: Merge release-with-assertions-no-lto profile into release-with-assertions: #91530
• improve allowedDevOrigins error: #91521
• Add group depth tracking to instant validation boundary discovery: #91208

Misc Changes

• [turbopack] Share scratch buffer across shards using thread local: #90167
• Turbopack: Use debug = "line-tables-only" for dev builds: #91539
• SRI turbopack documentation: #90477

Credits

Huge thanks to @lukesandberg, @bgw, @ztanner, @gnoff, and @richardjzhang for helping!

v16.2.0-canary.103

Core Changes

• Error when accessing undefined root params in generateStaticParams: #91519
• Buffer prefetch response before passing to Flight client: #91487
• [Segment Cache] Always upsert on prefetch completion: #91488
• Track vary params during runtime prefetches: #89297
• [react-sync] Allow locking in manual sync: #91509
• Remove devCacheControlNoCache experimental option (hard-code no-cache): #91503
• fix allowedDevOrigins for no-cors requests: #91506
• Remove webpack stats generation from Turbopack: #91515
• Upgrade React from c80a0750-20260312 to 3f0b9e61-20260317: #91522
• Move adapterPath from experimental to stable top-level config: #91535
• block disallowed dev origins by default: #91507

Misc Changes

• perf(turbopack-node): zero-copy Buffer transfer from node to rust: #91376
• docs(turbopack-core): Copy "layers" documentation from mdbook to rustdoc: #91350
• Turbopack: correctly apply effects for issue snapshots: #91511
• Turbopack: treat unknown CSS selectors as warnings: #91513
• docs(turbopack): Migrate chunking docs from mdbook, with proof-reading and minor updates from claude: #91472
• Skip catch-error-react-compiler test to unblock CI: #91528
• [turbopack] update qfilter to 0.3.0-alpha: #91467
• Unflake two "use cache" tests: #91529
• docs(turbopack): Remove old architecture.md file from turbopack crate: #91473

Credits

Huge thanks to @xusd320, @bgw, @mischnic, @unstubbable, @acdlite, @eps1lon, @devjiwonchoi, @lukesandberg, @sokra, @ztanner, and @timneutkens for helping!