Hacker News Reader

Comment by poincaredisk | Hacker News Reader

Good points in the OP. Instead of joining the distro war in the comments, I'll just note that NixOs builds may not be reproducible - because they often reuse non-reproducible building blocks, like makefiles or compilers which are also not reproducible - but NixOs maintainers spend a lot of time helping to improve the overall ecosystem and make builds more reproducible for everyone.

View on HN

I don't think it's fair enough. Look for example at their quoted source: https://reproducible.nixos.org/nixos-iso-minimal-r13y/ -- the way nix works allows for a mechanism to (almost*) check the reproducibility of the system, and it can show how reproducible it is for a complete build (99%).

In contrast, other distros like Debian have to rely on fuzzing to estimate this percent. Quoting from the FAQ:

> We don't currently inject randomness at the filesystem layer, but many of the reproducibility issues are being exercised already. It isn't possible to guarantee a package is reproducible, just like it isn't possible to prove software is bug-free. It is possible there is nondeterminism in a package source, waiting for some specific circumstance.

Read the page again.

What are they testing? 99% of what exactly?

What does "path" mean, does it inflate the number?

make and compilers are usually reproducible. Most Debian package are reproducible, so this is perfectly feasible.

You would think so, but after close to 10 years as a package maintainer it's clear to me that people don't know how make works when you do start doing anything else than `-j1`.

The gcc compiler also fails to reproduce binaries with the LTO streamer backend if you use certain macros. This has the consequence of making cgo binaries unreproducible.

As for Debian, we don't really know how many packages are reproducible. The CI they show is for fuzzing out issues, there are no system currently reproducing distributed packages.

Usually they aren't because of timestamps, processor features etc. After quite a bit of work Debian is now at 96% (or 93% when varying a few more things)

https://tests.reproducible-builds.org/debian/reproducible.ht...

Reply on news.ycombinator.com