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TypeScript 5.9 Iteration Plan #61648
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- pinned this issue
on May 2, 2025 Is the “Checked Returns for Conditional and Indexed Access Types” feature (originally #56941, now #61359) planned to re-land in 5.9?
(this feature was included in 5.8 beta, but reverted before the RC; Gabriela Araujo Britto (@gabritto) had mentioned the feature could re-land in 5.9)
Reacted by Md Fayaj NakibReacted by Damjan Polugic, Abdullah Ebrahim, Gabriel Rocha de Oliveira, Ramon Balthazar, Eli, tenzinhl, btoo and Lucas GenzelisWe're not planning on bringing that in for 5.9. We want to be more conservative about larger features that are more involved while so much of our attention is currently on the port.
Reacted by Matt Wade, Bnaya Peretz, Kirill Groshkov and Jayden PearseReacted by Md Fayaj Nakibunderstood, thanks for clarifying Daniel Rosenwasser (@DanielRosenwasser)
should we expect that that feature (or others of similar scope) won’t land in Typescript until 7.x?
i.e. should we expect it will never land in Strada—in order to avoid the additional development burden of trying to port a “moving target”—but instead the team will hold off until Corsa is ready to be the target of new features like this one?
(to be clear, that approach would not be at all unreasonable to me, just curious what to expect!)
Reacted by Md Fayaj NakibThere is a typo in planning table - all dates are for previous year :)
Reacted by Daniel Rosenwasser, Ramon Balthazar, Eli, Torleif Berger, Alex Crișan and Jayden PearseReacted by Md Fayaj NakibTautvydas Duda (@ltdu) fixed, thank you!
Luke Deen Taylor (@controversial) I can't say that for sure - we generally won't plan on new features, but it depends on priority, finding improvements that need to be backported during the port, etc. We just don't want to split our focus too much.
Reacted by Luke Deen Taylor, Honza Hrubý, Abdullah Ebrahim, Garrett Darnell, Szymon Nowak, Sean Vieira, Alex Crișan and Md Fayaj NakibHi! Is there any plan to include #59391, which is already at Stage 3?
(I understand if no given your other comments, but still asking because maybe JS features have higher priority)
Reacted by lin72hReacted by lin72h, Kirill Groshkov and Md Fayaj NakibReacted by Sébastien Lorber, Kenta Moriuchi, Rob Palmer and EliI hope #61236 will be included too.
Reacted by Md Fayaj NakibAny updates about release date? It seems RC version not released.
Reacted by Md Fayaj NakibReacted by Sébastien Lorber, Alexander Kachkaev, Danil Kochnev, Marco Massarotto, faulpeltz, honza-avvoka, Sean Callahan, Luke Deen Taylor, uhyo, Javier and 6 morePresumably we're too late for an
es2025target?Reacted by Karlis MelderisSorry for the delay all. It has been a busy while and so we're off schedule. Time to get things rolling again though!
TypeScript Bot (@typescript-bot) create release-5.9
Reacted by TypeScript Bot, Igor Samokhovets, tjc-travix, Matt Wade, Noel Kim, lin72h, Gualtiero, Toni Villena, Colin McDonnell and Alex CrișanReacted by Matt Wade, lin72h, Luke Deen Taylor, Gualtiero, Toni Villena, Javier, Colin McDonnell, Alex Crișan and Md Fayaj NakibReacted by Alexander Kachkaev, Danil Kochnev, Gualtiero, Alex Crișan and EliStarting jobs; this comment will be updated as builds start and complete.
Command Status Results create release-5.9✅ Started TypeScript Bot (@typescript-bot) create release-5.9
Reacted by TypeScript Bot, lin72h, Toni Villena and Alex Crișan17 remaining items
TS 5.9 is now available! Release blog post pending.
Reacted by Alexander Kachkaev, Madeline Gurriarán, lin72h, Javier, Toni Villena, btoo, wsporto, Noel Kim, Naoki Takahashi, Jayden Pearse and 4 moreReacted by Shinigami, Luke Deen Taylor, Madeline Gurriarán, lin72h, Toni Villena, btoo, wsporto, Noel Kim, Naoki Takahashi, MyOwnBrain and 2 moreReacted by Shinigami, René, Alexander Kachkaev, Madeline Gurriarán, Toni Villena, btoo, wsporto, Noel Kim, Naoki Takahashi, MyOwnBrain and 4 moreIs there also a plan for the next one?
Reacted by Ben Ayles, snarbles2, Danil Kochnev, Lucas Genzelis, Ghislain B. and Kirill GroshkovReacted by Md Fayaj NakibReacted by Aidan Temple, Peter Burns, YiJie and Kirill GroshkovTypeScript Bot (@typescript-bot) bump release-5.9
Reacted by TypeScript BotHey, Daniel Rosenwasser (@DanielRosenwasser)! I was unable set the version.
Check the logs at: https://github.com/microsoft/TypeScript/actions/runs/18022473945
TypeScript Bot (@typescript-bot) bump release-5.9
Reacted by TypeScript BotHey, Jake Bailey (@jakebailey)! I've set the version of release-5.9 to 5.9.3 for you.
Daniel Rosenwasser (@DanielRosenwasser) I think this issue can be closed since ts5.9 has been released for a few months
will there be a TS 5.10 or the team is focused on typescript 6 next?
Reacted by Kirill Groshkov, Sébastien Lorber, Madeline Gurriarán, Mouad Ennaciri, Geoffrey Parrier and Ghislain B.will there be a TS 5.10 or the team is focused on typescript 6 next?
I think part of your question can be answered by reading the Announcing TypeScript 5.9 blog post
What’s Next?
Now that TypeScript 5.9 is out, you might be wondering what’s in store for the next version: TypeScript 6.0.
As you might have heard, much of our recent focus has been on the native port of TypeScript which will eventually be available as TypeScript 7.0. So what does that mean for TypeScript 6.0?
and looking at the latest versions on NPM too, it's obvious that 6.0 will be the next release. Also FYI, there's never been any
x.10version since that is the transitioning number to their new major release (TypeScript doesn't follow semver for their release, they go from 0-9 as minor and then bump to a new major after that)
What I'm curious to know is when exactly is 6.0 supposed to come out? Because looking at the previous releases, November is typically a release month for TypeScript but December is almost here so... and also, will it include any major breaking changes? There's a couple that we can see in the 6.0 milestone and mostly this one #54500
It would be nice to get more news from core team though and/or an official planning issue like this one.
Reacted by Luke Deen Taylor, Kirill Groshkov and Toni VillenaStay tuned for a blog post (probably in the next week or so), but 6.0 will be later than the usual cadence. The issues you linked outline all our planned breaking changes for that release.
Reacted by Luke Deen Taylor, Nicolas Beaussart, Ghislain B., Alexander Kachkaev, lin72h, Kirill Groshkov and Md Fayaj NakibReacted by Sébastien LorberReacted by Sébastien Lorberyou can also look here: #62785
Reacted by Ryan Cavanaugh and lin72h- unpinned this issue
on Feb 3, 2026 The 6.0 iteration plan was just posted over at #63085.
Reacted by Ghislain B. and Toni VillenaReacted by Alexander Kachkaev and Toni Villena
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