Morgan :)

By chance I have a bit of spare time right now, it's too late on Friday to start something big :) sent a PR.

What do you mean by "corrupt the build cache"? It should not be possible to cause incorrect builds during normal use, so if you know a way to do so,...

In theory changes during the build should be okay, but it's not well tested. I'm actually just getting to the end of a refactor of this part of `build_runner`, so...

This is definitely a regression. That said, I'm not seeing a use case to allow `build.yaml` files that reference builders in other packages without also having a dependency on that...

Do you have this in a file called `build.yaml` in your package root folder? What do you mean by "scan"?

Skip based on the presence of `package:built_value/`, benchmark modified so most files do not use the builder. Without skip: ``` dart run _benchmark --generator=built_value --build-repo-path=$PWD/.. benchmark --size=2000 --mostly-no-codegen built_value shape,libraries,clean/ms,no...

> By that standard, we should be able to skip files that do import the annotation but never apply it within the library. I was going to ask for your...

It's mostly about skipping resolving elements. In the new log output, you can see the problem pretty clearly: a builder is listed as "no-op" if it runs but outputs nothing....

No, it matters just as much on incremental builds; see the last column in https://github.com/dart-lang/build/issues/4083#issuecomment-3048328311. The biggest improvement for incremental builds was 22s --> 9s for incremental builds by adding...

Interesting, thanks. `reportUnusedAsset` does not necessarily scale well: if you have to individually report unused assets for every build, that ends up having quadratic cost. (Inputs * number of unused...