This is the list of release activities needed for every TypeScript release. Additional activities are also needed if a new syntax is introduced or a new compiler option gets added.

The primary people managing a release should oversee these tasks along with the overall release process.

• Add all tslib updates
• Review next version number

Once main's version is updated, the @definitelytyped packages must be aware of the nightly's new version so that nightly versions of ATA continue to work. ATA relies on tsX.Y tags on @types/* packages.

• Update @definitelytyped/typescript-versions and @definitelytyped/typescript-packages to support the next version, update tests, and publish a new release.
  • in other words, if we're releasing TypeScript 3.9, DefinitelyTyped needs to support 4.0.
  • An example PR

• Tag release branch
• Draft and publish new release
• Close milestone corresponding to the release

• Review perf dashboard to identify regressions
• Review crawler-discovered crashes (and ensure these have been running) (and ensure these have been running)
• Review NewErrors breaking change issues (and ensure these have been running)

• Update What's new in TypeScript
• Update Breaking Changes
• Update API Breaking Changes

• Add new Release Notes page for the new release
• Update Handbook (As needed)

• Publish new version of typescript
• Publish new version of tslib (if needed) by creating a tag

• Publish new release to https://www.nuget.org/packages/Microsoft.TypeScript.MSBuild/

• Publish VS 2015 and VS 2017 installers under TypeScript team

• Update version of tsserver, test, and tag

After the release version is published to npm:

• Update @definitelytyped/typescript-versions: move the newly published version from supported to shipped (in the example above, that's 3.9), and publish a new release of @definitelytyped.

• Update Handbook
• Add new release notes page

When a new syntax or a new compiler option is introduced, find below the list of additional release activities needed:

• Add support for new option in MSBuild tasks and targets (see handbook)

• Add colorization support in TypeScript-TmLanguage

• Add parsing support in Babylon
• Add emit support to babel-plugin-syntax-typescript
• Update the TypeScript-Babel-Starter as needed

• Add new section for the new feature in the handbook