For CI builds we should explore the use of a fast transpiler, like SWC or esbuild. This would enable use to run (blocking) transpile, then in parallel run tests and TS type checking.

SWC transpile command: npx swc --config-file .swcrc src --copy-files --out-dir out

The joh/swc-branch has some changes that explore to use SWC for this. TODOs

• support for AMD - SWC just does that, great!
• we heavily rely on TS decorators for our injection story and need that to be supported. Good news is that latest SWC 1.2.186 has this fixed
• SWC doesn't hoist const enums swc/issues/3648 which isn't ideal for perf but also exposes some cyclic module dependencies that we have. We need to fix
  • Cyclic dependency: vs/workbench/contrib/markers/browser/constants and vs/workbench/contrib/markers/browser/markersTreeViewer #150291
  • Cyclic dependency: vs/editor/common/languages and vs/editor/common/tokenizationRegistry #150176
  • Cyclic dependency: vs/editor/common/viewLayout/lineDecorations and vs/editor/common/viewLayout/viewLineRenderer #150177
  • Cyclic dependency: vs/workbench/contrib/tasks/common/tasks and vs/workbench/contrib/tasks/common/taskService #150178
• The --copy-files flag doesn't seem to copy JS files (unclear if that's because they are compile-ignored or always seen as compilable resource)
• Workaround export import bug swc/issues/4481
• Local require-function is missing from AMD modules, swc/issues/4718
  • Local AMD require function not always called require swc-project/swc#4797
  • Local AMD require call sometimes missing swc-project/swc#4798
• Using a namespace before its declaration fails, swc/issues/4897
• Issue with import-require mixing, either avoid or wait for import foo = require should be normal AMD dependency swc-project/swc#4898
• Static factory function in decorated class uses un-decorated ctor swc-project/swc#4899