[joek1301]

> One hypothetical approach I could imagine, is that a dependency major-version release of a package can ship with AST-rewriting-algorithm code migrations

Jane Street has something similar called a "tree smash" [1]. When someone makes a breaking change to their internal dialect of OCaml, they also push a commit updating the entire company monorepo.

It's not explicitly stated whether such migrations happen via AST rewrites, but one can imagine leveraging the existing compiler infrastructure to do that.

[1]: https://signalsandthreads.com/future-of-programming/#3535

[swiftcoder]

This is more of less how Facebook developed PHP -> Hack on the fly. Each new language feature would be patched in, and at the same time, a whole-monorepo transform would be run to adopt the feature. Pretty neat, if a logistical nightmare