This document outlines our focused tasks for TypeScript 5.0. It minimally indicates intent to investigate tasks or contribute to an implementation. Nothing is set in stone, but we will strive to complete these tasks in a reasonable timeframe. Date | Event ---------------|------------------------- November 15th | TypeScript 4.9 Release January 20th | Create 5.0 Beta (5.0.0) Build for Testing January 24th | **TypeScript 5.0 Beta Release** February 24th | Create 5.0 RC (5.0.1) Build for Testing February 28th | **TypeScript 5.0 RC Release** March 10th | Create 5.0 Final (5.0.2) Build for Testing March 16th | **TypeScript 5.0 Final Release** 🚀 <!-- // %%{init: { 'theme': 'base', 'themeVariables': { 'primaryColor': '#4970b8', 'primaryBorderColor': '#fff', 'textColor': '#fff', 'secondaryColor': '#fff' }}}%% --> ```mermaid gantt dateFormat YYYY-MM-DD TypeScript 4.9 Stabilization Period : 2022-10-28, 2022-11-11 TypeScript 5.0 Beta Development : 2022-10-28, 2023-01-19 TypeScript 5.0 RC Development : 2023-01-19, 2023-02-24 TypeScript 5.0 Stabilization Period : 2023-02-24, 2023-03-16 todayMarker stroke-width:5px,stroke:#0f0,opacity:0.5 ``` ## Language and Compiler Features * [ECMAScript Decorators](https://github.com/microsoft/TypeScript/issues/48885) * [Unify All `enum`s as Unions](https://github.com/microsoft/TypeScript/pull/50528) * [Legacy Flag Deprecation](https://github.com/microsoft/TypeScript/issues/51000) * [Investigate Bundler-Oriented Module Resolution Options](https://github.com/microsoft/TypeScript/issues/50152) * [Support `.ts` as a Module Specifier for Bundler/Loader Scenarios](https://github.com/microsoft/TypeScript/issues/37582) * [Declaration Files for Non-JavaScript Files](https://github.com/microsoft/TypeScript/issues/50133) * [Allow Arrays in `extends` for `tsconfig.json` Files](https://github.com/microsoft/TypeScript/pull/50403) * [Investigate Per-File Settings](https://github.com/microsoft/TypeScript/pull/49886) * [`lib.d.ts` Updates](https://github.com/microsoft/TypeScript/issues/51361) * [Make `@types/web` Versionable](https://github.com/microsoft/TypeScript-DOM-lib-generator/issues/1383) ## Editor Productivity * [`switch`/`case` Snippet Completions](https://github.com/microsoft/TypeScript/pull/50996) * [Investigate `SharedArrayBuffer`-Backed Host for Web Editing Contexts](https://github.com/sandersn/vscode-wasm-typescript/) * [Investigate Limited ATA-Like Scenarios in Web Editing Contexts](https://github.com/microsoft/vscode/issues/172887) * [Implement Cancellation in Web Editing Contexts](https://github.com/microsoft/vscode/issues/148967) * [Easy Run/Debug for Loose TypeScript Files](https://github.com/microsoft/vscode/issues/124280) ## Performance * [Investigate Module Resolution Caching in `.tsbuildinfo` Files](https://github.com/microsoft/TypeScript/pull/41004) * [Optimizing `.tsbuildinfo`](https://github.com/microsoft/TypeScript/pull/51246) * [Investigate Tooling for JIT Deoptimizations](https://github.com/microsoft/TypeScript/issues/44211) ## Infrastructure * [Migrate TypeScript to Modules](https://github.com/microsoft/TypeScript/issues/35210) * [Enable `strictFunctionTypes` on TypeScript Codebase](https://github.com/microsoft/TypeScript/pull/49929) ## Website * [Make Onboarding and Cross-Platform Installation Smoother](https://github.com/microsoft/TypeScript-Website/issues/2500)