--- title: TypeScript 6.0 Migration Guide: What's Changed and How... description: A detailed migration guide covers anticipated breaking changes expected in TypeScript 6.0, explicitly flagged throughout as unverified pre-release speculation.... canonical: https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: TypeScript 6.0 Migration Guide: What's Changed and How to Update | daily.dev og:description: A detailed migration guide covers anticipated breaking changes expected in TypeScript 6.0, explicitly flagged throughout as unverified pre-release speculation.... og:url: https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg og:image: https://api.daily.dev/og/posts/CJiClvUkg.png og:image:alt: TypeScript 6.0 Migration Guide: What's Changed and How to Update og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # TypeScript 6.0 Migration Guide: What's Changed and How to Update **[SitePoint](https://daily.dev/sources/sitepoint)** · 16 min read · 5 upvotes · 0 comments ## Summary A detailed migration guide covers anticipated breaking changes expected in TypeScript 6.0, explicitly flagged throughout as unverified pre-release speculation. Key claimed changes include the `types` compiler option defaulting to an empty array instead of auto-including all @types packages, removal of the legacy `moduleResolution: classic` strategy, and built-in Temporal API type declarations in lib.d.ts that may conflict with polyfill packages. The guide provides concrete tsconfig.json diffs, error message examples, cross-platform commands for auditing installed @types packages, a prioritized migration checklist, and validation steps using tsc --noEmit and --extendedDiagnostics, while repeatedly urging readers to verify every claim against official TypeScript release notes before acting. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Will TypeScript 6.0 change the default value of the types compiler option? According to pre-release speculation, TypeScript 6.0 is expected to change types to default to an empty array instead of auto-including all @types/* packages from node_modules. This would mean projects relying on ambient packages like @types/node or @types/jest without listing them explicitly would fail to compile, producing errors like 'Cannot find name Buffer' unless every needed package is added to the types array. This has not been confirmed in any official TypeScript release note. _Track confirmed details on TypeScript upgrades like this on daily.dev before touching a production tsconfig._ ### How do I fix moduleResolution classic being removed in a future TypeScript version? Replace "moduleResolution": "classic" with node16 or nodenext for Node.js runtime projects, or bundler for front-end projects built with webpack, Vite, or esbuild. Run tsc --showConfig first, since classic can be silently inherited from an extended base tsconfig. Note that moduleResolution: bundler is incompatible with module: commonjs and requires an ESM-compatible module setting like esnext or preserve. _Developers planning a module resolution migration can follow tsconfig changes like these on daily.dev._ ### Why am I getting duplicate identifier errors for Temporal.PlainDate or Temporal.ZonedDateTime in TypeScript? Duplicate identifier errors like TS2300 for PlainDate or ZonedDateTime occur when a polyfill package such as @js-temporal/polyfill declares global Temporal types that collide with built-in lib.es2024.temporal.d.ts declarations shipped when targeting ES2024 or later. The fix is importing Temporal from the polyfill's module scope rather than relying on its global augmentation, or removing the polyfill entirely only if the target runtime natively supports Temporal. _Anyone debugging Temporal API type conflicts can find version-specific fixes like this on daily.dev._ ## Similar posts on daily.dev - [TypeScript 6.0 Migration: What Changed and How to Adapt Your tsconfig](https://daily.dev/posts/typescript-6-0-migration-what-changed-and-how-to-adapt-your-tsconfig-vs6jzygzz) · SitePoint · 0 upvotes · 0 comments - [Upgrading to TypeScript 6: A Real-World Migration](https://daily.dev/posts/upgrading-to-typescript-6-a-real-world-migration-wo1pvxrxk) · TypeScript.TV · 2 upvotes · 0 comments - [TypeScript 6.0 is your final warning](https://daily.dev/posts/typescript-6-0-is-your-final-warning-2tbdrcemi) · Bytes by ui.dev · 144 upvotes · 15 comments - [TypeScript 6.0 RC arrives as a bridge to a faster future](https://daily.dev/posts/typescript-6-0-rc-arrives-as-a-bridge-to-a-faster-future-uv04azmke) · The New Stack · 0 upvotes · 0 comments --- Tags: [#typescript](https://daily.dev/tags/typescript) [View this post on daily.dev](https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"TypeScript 6.0 Migration Guide: What's Changed and How to Update","url":"https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg"},"datePublished":"2026-08-15T22:33:06.977Z","dateModified":"2026-09-14T07:30:24.490Z","description":"A detailed migration guide covers anticipated breaking changes expected in TypeScript 6.0, explicitly flagged throughout as unverified pre-release speculation....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/bbd6cd150964558c93c40cf3c81532d4?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/bbd6cd150964558c93c40cf3c81532d4?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"SitePoint","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"SitePoint","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/sitepoint","url":"https://daily.dev/sources/sitepoint"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":5},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"typescript","timeRequired":"PT16M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"SitePoint","item":"https://daily.dev/sources/sitepoint"},{"@type":"ListItem","position":3,"name":"TypeScript 6.0 Migration Guide: What's Changed and How to Update"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/typescript-6-0-migration-guide-what-s-changed-and-how-to-update-cjiclvukg#faq","mainEntity":[{"@type":"Question","name":"Will TypeScript 6.0 change the default value of the types compiler option?","acceptedAnswer":{"@type":"Answer","text":"According to pre-release speculation, TypeScript 6.0 is expected to change types to default to an empty array instead of auto-including all @types/* packages from node_modules. 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