Go-based TypeScript to dramatically improve speed, scalability

Microsoft is developing a native TypeScript implementation based on Google’s Go language. The initiative promises dramatic improvements in editor startup speed, build times, and memory usage, making it easier to scale TypeScript to large code bases, Microsoft said.

Announced March 11, the plan involves porting the TypeScript compiler, tools, and code base from JavaScript to Go. Microsoft’s TypeScript team expects to be able to preview command-line type-checking in Go-based tsc by mid-2025, and to deliver a feature-complete Go implementation of TypeScript by the end of the year.

Developers who use Go-based TypeScript in the Visual Studio Code editor will feel the increased speed in the editor, Microsoft said. The company promises an 8x improvement in project load times, instant comprehensive error listings across entire projects, and greater responsiveness for all language service operations including completion lists, quick information, go to definition, and find all references. The new TypeScript will also support more advanced refactoring and deeper insights that were previously too expensive to compute, the company said. A demo video of the project is available here.

Microsoft expects developers to be “extremely excited” about this new development, because one of the most common pain points for users of the current, JavaScript-based TypeScript is that performance slows when it is used for large-scale apps, according to Microsoft.

Developers can build and run the Go code from a new working repo, offered under the same Apache License 2 license as the existing TypeScript code base. The JavaScript code base will continue development into the 6.x series. TypeScript 6.0 will introduce some deprecations and breaking changes to align with the upcoming native code base. When the native code base has reached sufficient parity with the current TypeScript, Microsoft will release it as TypeScript 7.0.

While some projects may switch to TypeScript 7.0 upon release, others may depend on certain API features, legacy configurations, or other constraints that require the continued use of TypeScript 6.0, Microsoft said. The JavaScript code base will be maintained in the 6.x line until TypeScript 7.x reaches sufficient maturity and adoption.