TypeScript 5.5 Beta Boosts Speed and Type Accuracy

TypeScript 5.5 Beta offers improved type inference, faster build times, and better JSX support for modern frontend frameworks.

Release of TypeScript 5.5 Beta

Microsoft announces the public beta of TypeScript 5.5, focusing on developer productivity and language precision.

Smarter Type Narrowing

Enhanced support for control flow analysis, especially with union and intersection types.

More accurate type resolution within if, switch, and logical conditions.

Speed Improvements

Build times reduced up to 15% on large codebases.

Optimized incremental builds with improved caching mechanisms.

Better JSX Handling

JSX type checking is more intuitive, benefiting frameworks like React, Solid, and Preact.

Improved inference when using children in component props.

New Utility Type: Awaited<T> Improvements

Better behavior when dealing with nested Promises.

Helps developers write cleaner asynchronous logic.

Import Type Enhancements

Expanded capabilities to import types directly from packages, reducing coupling and improving type safety.

Example: import("package").TypeName

Improved Editor Integration

Works seamlessly with VS Code 1.91+, providing faster autocomplete and better inlay hints.

Enhanced support for in-editor documentation and diagnostics.

Updated --moduleResolution Settings

New "node16" resolution mode defaulted in some configs.

Ensures compatibility with modern JavaScript project setups.

Compatibility with ECMAScript 2024

Adds support for upcoming ES2024 features like Set methods (Set.prototype.difference) and function decorators.

Developers can start experimenting with future syntax.

Community Feedback Welcome

Microsoft encourages developers to try out the beta and report issues or suggestions before the final release in late June 2025.