” If you are wondering why we are doing this at all, then hopefully the Reproducible Builds website will explain why this is useful.”<a href="https:&#x2F;&#x2F;reproducible-builds.org&#x2F;" rel="nofollow">https:&#x2F;&#x2F;reproducible-builds.org&#x2F;</a>Could you perhaps respond to the argumentation here?

It makes shipping backdoors a whole lot harder, yes.

Reproducible builds reduce the need for trusted parties.Have many organizations produce the binaries independently and post the arifacts.Once n of m parties agree on the arifact hash, take that as the trusted build.If every party reaches a different hash then we cannot build consensus.

There was perhaps no detected bug or attack. There have most likely been bugs or attacks that reproducible builds would have prevented.

There was no bug or attack on Debian since 2007 that reproducible packages would prevent.&quot;Well worth it&quot; is not correct. And it just ups the the contribution barrier to Debian higher, I already heard a lot of people complaining that contributing to Debian is hard and while in past I defended it by &quot;they need all the checks and bounds to make sure packages play with eachother nicely&quot;, this is just step that makes it hard for no reason and little benefit.

This is a huge achievement for Debian and the free software world.It took a while though until this was understood. In 2007 when pointing out on debian-devel that this is needed, I was still told what huge waste of time this would be. And indeed it took a huge amount of work by many people to get there, but it is well worth it.

Do you have JavaScript disabled? They put one of those anti-scraper things on it.

all I get is this:&gt; Forbidden&gt; &lt;p&gt;You are not allowed to access this!&lt;&#x2F;p&gt;(yes, with HTML tags on display) :)EDIT: I also found a &quot;I Challenge Thee&quot; page in history. did I just get blocked by antibot measures? why???

<a href="https:&#x2F;&#x2F;wiki.debian.org&#x2F;ReproducibleBuilds" rel="nofollow">https:&#x2F;&#x2F;wiki.debian.org&#x2F;ReproducibleBuilds</a> has some more infos; some is outdated, but it also has a chart showing how many packages are built in the CI, and how many of those are reproducible builds.(Orange = FTBR = &quot;failed to build reproducibly&quot;)I&#x27;m not good at reading numbers from charts, but I&#x27;d guess it&#x27;s a few percent (4-5ish?).

A great milestone, congrats Debian on taking a stance and holding high standards for yourself, especially in the current era.

I wonder why this is a thing nowadays. I use yocto for embedded devices and it was almost a no-brainer to implement reproducible builds. I can also easily enable Debian package management, so everything is already available.

Also, the *BSD are structured somewhat differently to a Linux distro.It&#x27;s not like the Linux world where you have distinct projects like the Kernel, GNU, OpenSSL, and then it&#x27;s the distributions job to assemble everything.In the BSD projects, the scope is developing and distributing an entire base system, i.e., the kernel but also the libc, the shell&#x2F;all posix utilities, and a few third parties like OpenSSH (which are usually &quot;softforked&quot;).It&#x27;s quite visible in the sources, it&#x27;s a lot more than just a kernel:
<a href="https:&#x2F;&#x2F;github.com&#x2F;NetBSD&#x2F;src" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;NetBSD&#x2F;src</a>Additional packages you could get from pkg_in&#x2F;pkgsrc (NetBSD), pkg-ng&#x2F;ports (FreeBSD) or pkg_add (OpenBSD) are clearly distinct from the base system, installed in a dedicated subtree (&#x2F;usr&#x2F;src in NetBSD, &#x2F;usr&#x2F;local&#x2F; OpenBSD&#x2F;FreeBSD), and provided in a best effort manner.The reproducible build target was almost certainly only for the base system, which is a few percent of what Debian tries to achieve, and on which NetBSD has a tighter control over (developer + distributor instead of downstream assembler+distributor).A reproducible base system is useful, but given how quickly you typically need to install packages from pkgsrc, it&#x27;s not quite enough.

As pointed in your link, NetBSD achieved this with some help from Debian. If I understand correctly, it&#x27;s not that NetBSD tried harder, it&#x27;s that their problem was easier: fewer packages which change less (they still use CVS, &quot;stability&quot; is an understatement!).BTW, most Debian packages have reproducible builds. Those which have not (I&#x27;d say 5%) are shown in orange in the graph there: <a href="https:&#x2F;&#x2F;wiki.debian.org&#x2F;ReproducibleBuilds" rel="nofollow">https:&#x2F;&#x2F;wiki.debian.org&#x2F;ReproducibleBuilds</a>

That distro has smaller codebase than Debian Installer.

While we are bragging, stagex was the first to hit 100% full source bootstrapped deterministic and hermetic builds last year and the first to make multiple signed reproductions by different maintainers on their own hardware mandatory for every release.Debian has come along way, but when Debian says reproducible they mean they grab third party binaries to build theirs. When we say reproducible we mean 100% bootstrapped from source code all the way through the entire software supply chain.We think that distinction matters.<a href="https:&#x2F;&#x2F;stagex.tools" rel="nofollow">https:&#x2F;&#x2F;stagex.tools</a>

Good thing. NetBSD has fully reproductible build since 2017. <a href="https:&#x2F;&#x2F;blog.netbsd.org&#x2F;tnf&#x2F;entry&#x2F;netbsd_fully_reproducible_builds" rel="nofollow">https:&#x2F;&#x2F;blog.netbsd.org&#x2F;tnf&#x2F;entry&#x2F;netbsd_fully_reproducible_...</a>

I can see it just fine; maybe an overzealous firewall thinks you&#x27;re a bot? At any rate, the Wayback Machine has it: <a href="https:&#x2F;&#x2F;web.archive.org&#x2F;web&#x2F;20260510074120&#x2F;https:&#x2F;&#x2F;lists.debian.org&#x2F;debian-devel-announce&#x2F;2026&#x2F;05&#x2F;msg00001.html" rel="nofollow">https:&#x2F;&#x2F;web.archive.org&#x2F;web&#x2F;20260510074120&#x2F;https:&#x2F;&#x2F;lists.deb...</a>

ForbiddenYou don&#x27;t have permission to access this resource.
Apache Server at lists.debian.org Port 443:&#x2F;

Probably easiest way is to use Bazel to leverage the effort that has gone in there

Has anyone fought Microsoft Visual Studio successfully to produce reproducible builds of C++ programs? From what I have heard, it is one of the worst contexts to do it.

So much time has been wasted on reproducible builds which could have better spent on securing more important parts of Debian. Practically minor changes like a build timestamp being different is not an issue.

As someone who recently spent a lot of time on making a large C++ program entirely reproducible on 4 different OS’es, one cannot understate just how many tiny details matter here.

A small step for debian,giant leap for mankind.

In the end, Nix is just a thin veneer on this stuff.Given how many quick &amp; dirty sed patching or exec commands I&#x27;ve seen in the few nix package&#x2F;modules I&#x27;ve read, I would not exactly bet my life on it being completely idempotent &amp; reproducible.

Debian, like any other legacy distro, mush became declarative, because the &#x27;80s model of manual deploy and the absurd pain of D&#x2F;I and Preseed must end.

no problem in Debian since the start of the effort would be solved by reproductible buildsThis is nice pat yourself on the back achievement for people that prefer security theatre and checking boxes than doing something actually useful, and they wasted thousands man hours of poor victims that had to implement it

&gt; zero improvement on end-user experience.Maybe not by itself, but it does allow for the ecosystem to be audited, in a way that ultimately benefits the end-user. It really is an important part of a healthy supply chain.

This is some of the best news I&#x27;ve heard recently when it comes to figuring out how to produce high quality Software Bills of Materials for the upcoming EU Cyber Resilience Act, for what it&#x27;s worth. Reproducible packages are actually worth a great deal when you are selling products with digital elements. Much easier to scan through, audit, etc. with confidence.

&gt; for example the stream of issues from npm et al.Curious, what distros where affected by npm supply chain attacks?

Debian has had a better &quot;software supply chain&quot; posture than any other player in the ecosystem since before the turn of the century. While we all face the risk of malware from upstream, Debian is the least at risk of being affected by it. See for example the stream of issues from npm et al. None of it has affected Debian.

Has there been a single publicly known attack that would have been prevented by this?

It does not solve all supply chain issues, it do solve some supply chain issues.Not being able to see if the source code shipped is the same as been used for creating the binary is scary

Reproducible builds shows that, within a specific configuration, the code produced the binary, regardless of who signed or published it.Indeed, this could mitigate an attacker replacing the binary with something that&#x27;s not produced from the code, but it does not mitigate the tool chain or code itself containing the exploit, creating a malicious binary.

That&#x27;s not what reproducible builds aim to prevent, and no one claims that. When upstream pushes bad code, that&#x27;s on upstream.The thing reproducible builds aim to prevent is Debian or individual developers and system administrators with access rights to binary uploads and signing keys to get forced to sign and upload binary packages by attackers - be these governments (with or without court orders) or criminal organizations.As of now, say if I were an administrator of Debian&#x27;s CI infrastructure, technically there would be nothing preventing me from running an &quot;extra&quot; job on the CI infrastructure building a package for openssh with a knock-knock backdoor, properly signing it and uploading it to the repository. For someone to spot the attack and differentiate it, they&#x27;d have to notice that there is a package in the repository that has no corresponding build logs or has issues otherwise.But with reproducible builds, anyone can set up infrastructure to rebuild Debian packages from source automatically and if there is a mismatch with what is on Debian&#x27;s repository, raise alarm bells.

If you find yourself holding opinions of the kind: &quot;If it can&#x27;t be made perfect, it shouldn&#x27;t be changed at all?&quot; you may want to consider that most things that work well today were incrementally improved.Reproducable builds are not solving all issues as you rightly observed, but they can be a stepping stone (or even a pre-condition) for further measures.

Well - reproducible also means code guarantee. It may not improve an end-user experience directly, but you get an extra quality control step, as guarantee, here. I think reproducibility is great. If we can achieve that, it should be achieved. See also NixOS; it can guarantee that snapshot xyz works, not just for one user, but ALL users. I see it as hopping from guarantee to guarantee. That&#x27;s actually a good thing in the long run. Just think differently here.

&gt; zero improvement on end-user experienceThe end-user experience is that now you can host your Debian binaries in caches and CDNs without worrying about supply chain hackers.You can verify that file hashes match the ones on Debian&#x27;s website and sleep much better at night.If you don&#x27;t trust Debian&#x27;s website then you can rebuild yourself and check if Debian has been compromised.

zero improvement on end-user experience. does not solve supply chain issues, debian package will reproducabily contain the malware from upstream.

Debian must ship reproducible packages