alt Hacker NewsAh you're right, the hash wouldn't be the same but a Dockerfile could produce different outputs on different machines whereas nix will produce identical output on different machines.
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verdverm • today at 1:04 AM
If you are building a binary on different arches, it will not be the same. I have many container builds that I can run while disabling the cache and get the same hash/bytes in the end, i.e. reproducible across machines, which also requires whatever you build inside be byte reproducible (like Go)
Producing different outputs isn't dockerfile's fault. Dockerfile doesn't enforce reproducibility but reproducibility can be achieved with it.
Nix isn't some magical thing that makes things reproducible either. nix is simply pinning build inputs and relying on caches. nixpkgs is entirely git based so you end up pinning the entire package tree.