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TypeScript 6.0 Iteration Plan #63085
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on Feb 3, 2026 I've submitted a PR to add the ES2025 target (#63046), but will this not be included in TypeScript 6.0?
Reacted by uhyo, Luke Deen Taylor, Frulfump, ken7253, lin72h, roottool, Matthew Gamble and AFCMSYou can lump that in with lib.d.ts updates.
Reacted by Luke Deen Taylor, Frulfump, lin72h, Matthew Gamble and AFCMSReacted by Kenta Moriuchi and AFCMSTypeScript Bot (@typescript-bot) create release-6.0
Reacted by TypeScript Bot and Matthew GambleHey, Daniel Rosenwasser (@DanielRosenwasser)! I've created release-6.0 with version 6.0.0-beta for you.
Reacted by Kenta Moriuchi, lin72h, Toni Villena, Connor Shea, Javier, Alexander Kachkaev and Jake ColbertDeprecate less-used --module targets (AMD/System/UMD)
The PR #62669 (comment) deprecated
--module=none, too.
Not sure if this really qualifies as "less-used" in the wild.2026-02-21 | Create 6.0 RC (6.0.1) Build for Testing
2026-02-24 | TypeScript 6.0 RC Releaseping. are there any updates when RC/test build arrives?
could any dev build existing today be considered as test build quality?Reacted by Ryan Cavanaugh, Luke Deen Taylor and lin72hSorry, there's a few library changes we want to make but the RC should be out within the next week. Any dev build today is stable and usable though.
Nightly builds re available via installing
typescript@nexton npm and the VS Code Marketplace.Reacted by Ghislain B. and Thibaut SABOTReacted by Vinayak SoniTypeScript Bot (@typescript-bot) sync release-6.0
Reacted by TypeScript BotHey, Daniel Rosenwasser (@DanielRosenwasser)! I've pulled main into release-6.0 for you.
TypeScript Bot (@typescript-bot) bump release-6.0
Reacted by TypeScript Bot and lin72h16 remaining items
That run is unrelated to a release.
Okay, thank you. Do you have a specific release date?
Reacted by Maksim, Gualtiero, TooNew, zglicz, Daniel L, MgmClientGuy0, Pavlo Vuiko, Levin Bänninger, Amit Prakash Ambasta, Christopher S. Case and 9 moreHere's me telling the team it would release on the 17th - now I look quite the fool! :P
No rush, of course; everyone knows software dates aren't real.
Reacted by Maksim, Daniel L and Ryan CavanaughReacted by lin72h, TooNew, Elaina Cherudim, Pavlo Vuiko, Evgenii Kalkutin, Daniel L, DOMArtist, Barthélemy Paléologue and Ryan CavanaughReacted by lin72h, TooNew, Hans Bakker, Vladyslav Huba, Daniel L and Kenta MoriuchiWe hit some issues when testing in Visual Studio, so 23 is the new 17
Reacted by Daniel L, Alexander Kachkaev, Kai, Pavlo Vuiko, Simon Buchan, Madeline Gurriarán, lin72h, ocavue, Chen, Zhi-Yuan, roottool and 14 moreReacted by Holger Jeromin, lin72h, lajczi, TooNew, Gualtiero and Prakhar AgarwalReacted by Denis Mukhametov, lajczi, Gualtiero and Alexander Kachkaev6.0.0 RC was already released, see https://devblogs.microsoft.com/typescript/announcing-typescript-6-0-rc/ or
npm install typescript@rc- Reacted by Denis Mukhametov, Gualtiero, Idan Goshen, Guillaume Humbert, Scott Bai, Matt Kantor, Kirk Waiblinger, Maksim, Daniel L, Tyler Church and 11 moreReacted by Alexander Kachkaev, Denis Mukhametov, Gualtiero, Idan Goshen, Daniel L, lin72h, Toni Villena, Madeline Gurriarán, Daniel Yogel and EliReacted by Alexander Kachkaev, Denis Mukhametov, Gualtiero, Idan Goshen, Daniel L, lin72h, Toni Villena, Madeline Gurriarán, Nicolas Stepien, Daniel Yogel and 2 more
I think #63290 is basically within scope, though I agree there is some room for interpretation.
I realize this may still be below the intended bar for post-6.0 patches, but the closest fit seems to be the first criterion:
- Crashes that were introduced in 5.9 or 6.0 that also repro in 7.0 and have a portable fix and don't incur other behavioral changes
Why I think it is at least a reasonable fit:
#63290fixes failure handling in the built-in CPU profiling path insrc/compiler/sys.ts.- Today, if
Profiler.enableorProfiler.startfails, the error callback is ignored and the connected inspector session can be left in a bad state in a user-facing diagnostic path. - The fix is narrow and success-path-neutral: it only handles the error callback case, disconnects the session, and then continues without changing normal profiler behavior.
- There is also a corresponding profiling-startup cleanup fix in 7.0 at microsoft/typescript-go#3216. It is not the exact same codepath, so I do not want to overstate that point, but it does suggest this is a portable bug class rather than a 6.0-only concern.
If the team thinks this still does not meet the bar, no problem. But given the small scope, lack of intended behavioral change, and the parallel 7.0 fix, I thought it was worth asking whether #63290 should be considered under that first criterion.
I do not think that meets the bar for a whole patch to TS 6.0, given the low usage and very rare failure situation for what is effectively a debugging feature. (The PR is also very broken, so cannot be reviewed in its current form anyway...)
Reacted by Ryan Cavanaugh, Tay and lin72hWe hit some issues when testing in Visual Studio, so 23 is the new 17
I am really happy that you test with the paid product.
Would love to have a nuget release. (ref #62236)
https://www.nuget.org/packages/Microsoft.TypeScript.MSBuild
Edit: done "a day ago". Thanks
Reacted by lin72h and Ryan CavanaughTypeScript Bot (@typescript-bot) bump release-6.0
Reacted by TypeScript BotHey, Daniel Rosenwasser (@DanielRosenwasser)! I've set the version of release-6.0 to 6.0.3 for you.
about the typescript part — switched to this recently and the performance difference is night and day compared to what i was using
The TypeScript 7.1 iteration plan has been posted over at #63703!
Reacted by Luke Deen Taylor, Kirill Groshkov, Guillaume Humbert, Eli, DOMArtist and lin72hReacted by Luke Deen Taylor, Kirill Groshkov, Kai, Eli, DOMArtist and lin72h- unpinned this issue
on Aug 17, 2026
Compiler and Language
this-less functionsexactOptionalPropertyTypes#/--module commonjsand--moduleResolution bundlerlib.d.tsupdates for 6.0Breaking Changes and Deprecations
See the broader discussion at 6.0 Deprecation Candidates
--target es5and adjust lowest target toes2015--outFilebaseUrl--moduleResolution node10--moduleResolution classicmodulein place ofnamespace/// <reference no-default-lib />/// <amd-module name=... />--moduletargets (AMD/System/UMD)--downlevelIterationDefaults and Behavioral Changes
--strictby default"use strict"everywhere by default--targetto latest ECMAScripttsconfig.jsontypesto[]intsconfig.jsonrootDiris the config directory--noUncheckedSideEffectImportsby defaultlibReplacementtofalse