esbuild-runner VS TS-ESNode

You can then use esbuild-runner to allow you to run tests written in TS. This will also work for any other test runner (mocha, tape, uvu, etc). Jest requires a bit more fiddling, as per usual. An alternative is running tests via TS-node, but it's little a bit slower.

via ESbuild https://github.com/folke/esbuild-runner

CommonJS is a great module system if you're using JS for scripting Unix (which it excels at). Is there a good reason to use ESM though? I've been half-joking that it's the "extinguish" phase of Microsoft's EEE strategy for JS.

I know one legitimate reason is "tree shaking" (source-level LTO when bundling modules). Dumber, static import/export statements probably simplify that in some way. However ESM destroys the isomorphism between JS modules and the filesystem.

One change that ES modules introduced, I think, for no other reason than to be backwards incompatible, is changing the behavior of the default export (`export default foo` transpiles down to `module.exports.default = foo` instead of `module.exports = foo`).

Other "ohai guys this is the new normal now" kinds of changes are making the dynamic imports async-only (after not supporting them for a while) as well as changing the behavior of module resolution.

And the cherry on top is called TS-ESNode: https://github.com/K-FOSS/TS-ESNode because TypeScript modules and ESM are the same thing yet you need to somehow find this third-party shim which is required for them to work together at all. It's enabled by wrapping the interpreter, just like Yarn2's new dependency resolution.