I have thought about this in regards to Nix but as far as I could conceive, it seemed that: a) you can definitively generate content that will be hashed to the

I have thought about this in regards to Nix but as far as I could conceive, it seemed that: a) you can definitively generate content that will be hashed to the same value - this is a given since anything that compresses a source into a much shorter representation allows that by definition (lets ignore feasibility/time/cost) b) Making a) in a way that the contents are usable for a given purpose, doesn't introduce severe noticeable changes, and plays ball with the remaining stuff (OS, build chains, the context where it's included in, etc) seems to be the actual difficult part So my conclusion was at the time that in terms of feasibility it's probably easier to hack the chain itself replacing the hash. But again, if there's a master "hash" for whatever artefact is produced that relies on all those hashes it would also need to be replaced?