This document outlines our focused tasks for TypeScript 3.9, as well as some of the discussion that explains how/why we prioritized certain work items. Nothing is set in stone, but we will strive to complete them in a reasonable timeframe. Date | Event --------------|------------------------ February 20th | TypeScript 3.8 Release (past) March 20th | Create 3.9 Beta (3.9.0) Build for Testing March 24th | **TypeScript 3.9 Beta Release** April 24th | Create 3.9 RC (3.9.1) Build for Testing April 28th | **TypeScript 3.9 RC Release** May 8th | Create 3.9 Final (3.9.2) Build for Testing May 12th | **TypeScript 3.9 Final Release** 🚀 # Work Items ## Expected Work Items * Stability * [Eliminate crashes](https://github.com/microsoft/TypeScript/labels/Crash) * Address compiler-bound crashes first, typically impact the LS too. * Assign priorities to crashes from telemetry and fuzzing * Compiler team addresses work items * Investigate better TSServer logging for easier issue reports * Performance * Investigative * Work with users * Improve build times for popular libraries * Giant unions (MUI and styled-components) * Update Perf Suite * Current Compiler * Code using popular libraries * [Parallelized `--build` mode for project references](https://github.com/Microsoft/TypeScript/issues/30235) * [Lazy-loading projects in preview tabs](https://github.com/microsoft/TypeScript/issues/35114) * Infrastructure * [Moving to modules](https://github.com/microsoft/TypeScript/pull/35561) * Helps us catch module issues sooner * Eventually can be the basis of solving [package size issues](https://github.com/microsoft/TypeScript/issues/27891) * [Pull Request Debt](https://github.com/microsoft/TypeScript/pulls) * [Automate more release activities](https://github.com/microsoft/TypeScript/issues/37196) * Compiler work * [The `awaited` type](https://github.com/microsoft/TypeScript/pull/35998) * [Live bindings for getters](https://github.com/microsoft/TypeScript/pull/35967) * [lib.d.ts Updates](https://github.com/microsoft/TypeScript/issues/37197) * [Bug Squashing!](https://github.com/Microsoft/TypeScript/issues?q=is%3Aopen+is%3Aissue+label%3ABug+milestone%3A%22TypeScript+3.9.0%22) * Editor Productivity and Language Service * [VS Code Priority bugs](https://github.com/microsoft/TypeScript/issues?q=is%3Aopen+is%3Aissue+label%3A%22VS+Code+Priority%22) * [Investigate Discoverability for Refactorings/Quick Fixes](https://github.com/microsoft/TypeScript/issues/34859) * [Switch ATA to GitHub Package Registry](https://github.com/microsoft/TypeScript/issues/33330) * Tentative: blocked on un-authenticated downloads * Command Line Tooling * [downlevel-dts](https://github.com/sandersn/downlevel-dts) * Move to Microsoft organization * Set out policies/contribution guidelines * Provide documentation and workflow guidance * Documentation * [Handbook](https://github.com/Microsoft/TypeScript-New-Handbook/) * [Website](https://github.com/microsoft/TypeScript-Website/issues/94) * [Clarify Contributing Guidelines](https://github.com/microsoft/TypeScript/issues/34785)