TypeScript 7

Not sure what this is? Read the announcement post!

Preview

A preview build is available on npm as @typescript/native-preview.

npm install @typescript/native-preview
npx tsgo # Use this as you would tsc.

A preview VS Code extension is available on the VS Code marketplace.

To use this, set this in your VS Code settings:

{
    "typescript.experimental.useTsgo": true
}

What Works So Far?

This is still a work in progress and is not yet at full feature parity with TypeScript. Bugs may exist. Please check this list carefully before logging a new issue or assuming an intentional change.

Feature	Status	Notes
Program creation	done	Same files and module resolution as TS 5.8. Not all resolution modes supported yet.
Parsing/scanning	done	Exact same syntax errors as TS 5.8
Commandline and tsconfig.json parsing	mostly done	Missing --help, --init.
Type resolution	done	Same types as TS 5.8.
Type checking	done	Same errors, locations, and messages as TS 5.8. Types printback in errors may display differently.
JavaScript-specific inference and JSDoc	in progress	Mostly complete, but intentionally lacking some features. Declaration emit not complete.
JSX	done	-
Declaration emit	in progress	Most common features are in place, but some edge cases and feature flags are still unhandled.
Emit (JS output)	in progress	target: esnext well-supported, other targets may have gaps.
Watch mode	prototype	Watches files and rebuilds, but no incremental rechecking. Not optimized.
Build mode / project references	done	-
Incremental build	done	-
Language service (LSP)	in progress	Some functionality (errors, hover, go to def, refs, sig help). More features coming soon.
API	not ready	-

Definitions:

• done aka "believed done": We're not currently aware of any deficits or major left work to do. OK to log bugs
• in progress: currently being worked on; some features may work and some might not. OK to log panics, but nothing else please
• prototype: proof-of-concept only; do not log bugs
• not ready: either haven't even started yet, or far enough from ready that you shouldn't bother messing with it yet

Other Notes

Long-term, we expect that this repo and its contents will be merged into microsoft/TypeScript. As a result, the repo and issue tracker for typescript-go will eventually be closed, so treat discussions/issues accordingly.

For a list of intentional changes with respect to TypeScript 5.7, see CHANGES.md.

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit Contributor License Agreements.

When you submit a pull request, a CLA bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., status check, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact [email protected] with any additional questions or comments.

Trademarks

This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow Microsoft's Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.