TypeScript 5.9 Iteration Plan
Opened this issue · 38 comments
| Date | Event |
|---|---|
| 2025-02-25 | TypeScript 5.8 Release |
| 2025-05-23 | Create 5.9 Beta (5.9.0) Build for Testing |
| 2025-05-26 | TypeScript 5.9 Beta Release |
| 2025-06-13 | Create 5.9 RC (5.9.1) Build for Testing |
| 2025-06-17 | TypeScript 5.9 RC Release |
| 2025-07-18 | Create 5.9 Final (5.9.2) Build for Testing |
| 2025-07-22 | TypeScript 5.9 Final Release 🚀 |
Compiler and Language
tsc --initUpdates- 6.0 Deprecation Plans
- Investigate Cyclic Project References
node20Resolutionlib.d.tsUpdates
Editor and Language Service
Performance
We'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.
understood, thanks for clarifying @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!)
There is a typo in planning table - all dates are for previous year :)
@ltdu fixed, thank you!
@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.
Hi! 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)
I hope #61236 will be included too.
Any updates about release date? It seems RC version not released.
Presumably we're too late for an es2025 target?
Sorry 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 create release-5.9
Starting jobs; this comment will be updated as builds start and complete.
| Command | Status | Results |
|---|---|---|
create release-5.9 |
✅ Started |
@typescript-bot create release-5.9
Hey, @DanielRosenwasser! I've created release-5.9 with version 5.9.0-beta for you.
Super excited about this release! Especially #59940
Given that the beta was created ~1 month behind schedule, is it reasonable to expect that the final release will also happen ~1 month after what's stated in the plan in the original post?
I'll try to get an updated schedule out soon. The beta is now available though!
We tried out beta and nightly of typescript v5.9 and either I do something wrong, or the --module node20 does not work yet 👀
https://github.com/faker-js/playground/actions/runs/16199996411/job/45736292072?pr=50#step:8:25
You're setting --moduleResolution node20, not --module node20.
(Note that this issue is not the place to report issues with the beta; please file issues for those.)
Okay, news everyone: we are targeting a new release date for the stable release: July 29th. Given that, we'll be releasing 5.9 RC within the next few days (early next week at latest).
A lot of our work has been going into 7.0 (the native port) and understanding what 6.0 will likely deprecate as a stepping stone for people to move towards 7.0. More details on this to come.
@typescript-bot sync release-5.9
Hey, @DanielRosenwasser! I've pulled main into release-5.9 for you.
@typescript-bot bump release-5.9
Hey, @DanielRosenwasser! I've set the version of release-5.9 to 5.9.1-rc for you.
5.9 RC is out, blog post will be coming soon, but we haven't made drastic changes since the beta.
@typescript-bot bump release-5.9
Hey, @DanielRosenwasser! I've set the version of release-5.9 to 5.9.2 for you.
TS 5.9 is now available! Release blog post pending.
Is there also a plan for the next one?
@typescript-bot bump release-5.9
Hey, @DanielRosenwasser! I was unable set the version.
Check the logs at: https://github.com/microsoft/TypeScript/actions/runs/18022473945
@typescript-bot bump release-5.9
Hey, @jakebailey! I've set the version of release-5.9 to 5.9.3 for you.