Like everything else with Gnu, the main difference seems to be philosophical. Guix is fundamentally opposed to pre-compiled binaries. Nix has no issue with them.
Using pre-compiled binaries means that builds aren't reproducible, a goal of both Nix and Guix.
Binaries can be signed to prove that the chain of trust is unbroken between the vendor (who maybe you trust enough to run their software on your systems) and you. In the case of a system with reproducible builds, that signature also says, "if you were to build this yourself, you'd end up with the same binary I am sending you."
Edit: I am beginning to realize that when davexunit says "pre-compiled binaries" they are not talking about an OS vendor (like Guix) distributing a binary package (with source available). They are talking about binary blobs provided by third parties, and in a form that is not reproducible, such as an nvidia driver kernel blob. This has led to me assuming davexunit is nuts, but apparently it is just that neither of us has been speaking very clearly to each other, and thus we've seemingly been talking past each other.
[0] https://reproducible-builds.org/
[1] https://www.gnu.org/software/guix/manual/html_node/Bootstrap...
Every binary in the chain can be signed and reproducible (theoretically; we aren't quite there, realistically speaking, and the bootstrap, as you note, is tricky). Forcing every user to build everything from source every time is just a mess, and provides little benefit over signed (reproducible) binaries for the vast majority of users.
It sounds like you (and the guix project) are conflating two orthogonal concepts and making "reproducible builds" into a concept that won't work in widespread use, and maybe even has negative value. We want reproducible builds so that we can be certain that the binary a vendor ships us is built exactly the way they say it was. We don't want it so that everyone is forced to build everything from scratch every time.
Reproducible builds means we can build an identical binary from source to prove that it is what we think it is. It should not mean we must build an identical binary from source every time we install a thing.
We don't want this either :) Let's not boil the oceans.
Nix and Guix are both a hybrid of build-from-source and binary package management systems. The package recipes and management tools describe how to build some software from source, and then transparently provide binaries for those recipes when the binary is available from a user-approved provider of the binaries.
But, by providing the full build recipes, all the way down to the bootstrap, users can easily rebuild binaries from source to check that their selected binary provider is honest, or to find reproducibility bugs.
In the case of a package recipe for some software that does not have source code available (a binary "blob"), the recipe would just download the blob from somewhere. We don't package those things in Guix, whereas Nix does. Although, it's not hard to make custom recipes that would do that, if you wanted to.
I have no problem with Guix being ideologically pure. Only with the notion that you can't have a reproducible build without forcing everyone to build it it themselves, which it seems is not the case with Guix. Cool.
>We don't want it so that everyone is forced to build everything from scratch every time.
I believe it is you who is confused. I never suggested this is what reproducible builds are about.
https://www.gnu.org/software/guix/manual/html_node/Substitut...
SwellJoe: Go back and substitute "source verifiable" every time davexunit says "reproducible" and everything he says makes sense.
davexunit: Read everyone else's comments from the POV where "reproducible" mean "reliable bitwise replication" without consideration of scientifically reproducible experiments or source verification, and everything they say makes sense.
I interpreted your statement of "Using pre-compiled binaries means that builds aren't reproducible, a goal of both Nix and Guix" to mean, "Guix does not distribute pre-compiled binaries, because they can't be reproduced". That still seems an entirely reasonable interpretation of that sentence, to me, as someone with no familiarity with Guix.
But, I now see that your intended meaning was that Guix does not distribute stuff like nvidia blobs, or Flash player, which is a perfectly reasonable choice for them, and nothing less than I would expect of a GNU project (and Fedora, my current favorite desktop distro, has the same policy, so I don't have a problem with it).
For example, the Haskell toolchain in nixpkgs downloads pre-compiled binaries of old GHC versions (7.0.4 and 7.4.2) which it uses to bootstrap the newer versions.
The binaries are checksummed to ensure reproducibility.
The same way: cryptographic signatures and checksums.
M-x passive-agressive-mode