ESBuild does not support any AST transforms directly

You can add it, via plugins, but its a serious limitation for a project like Next.js which require's these types of transforms

You also end up with diminishing returns with the more plugins in you add to esbuild, and I imagine its worse with js plugins than it is with go based ones, none the less, you have zero access to it directly

I never said it supports AST transformations directly. I just said they were trivial to do with esbuild.

Our build times remain at 0.5s with pretty extensive source transformers in JavaScript plugins in esbuild. This is down from 5-8 minutes using rollup.

I'd need a lot more context to understand what you mean by "trivial" and "extensive", respectfully

It is trivial to write extensions for esbuild. We've written extensive plugins to perform ast transformations that all run, collectively, in under 0.5 seconds.

Make a plugin, add acorn and escodegen. It isn't difficult.

I don't see what is difficult to understand.