Well, so that's been key to our claim about incremental migrations, though: when setting ICs, you only need to reason about the ICs of the code itself, not all of its transitive deps. "Is this particular library file compatible w/ both Py2 and Py3?" Pants/Pex will handle the transitive deps. You will of course need to make sure it's all compatible, which for example the

py-constraints

goal helps with. But key to it is the assumption that each target's ICs represent that files own compatibility, not its deps By freeing you up to only reason about the particular file's code, we unlock incremental migrations. You can focus on porting a single file at a time and accurately represent its migration status by setting its IC field