Nice addition on top of Dagger — sounds conceptually similar to the now-defunct Earthly.
Just one comment: please, no YAML. Anything but YAML/JSON — PKL, Starlark, TypeScript, you name it.
True, but they are so much complex (and much more powerful). This is more an equivalent to turborepo, minimal config and integrate directly with the language.
I agree, it can be done with a makefile, just except the dependency based runner, if you have module A depending on B, you want to test A and B, this is what a tool like bazel would solve, as well as monogo.