Sure. Given code which works for a lot of people, versus some organization composed of people, the fault is probably with people and not with code. This follows from the formal properties of code as mathematical objects, plus the property of probabilistically-checked proofs: If code works for a lot of people, then the code is expected to work generally with high probability.
Moreover, there are lots of folks having professional success with Nix, and having consumed enough of their stories, I think that the stumbling blocks that the parent identified are faults of their organization and not of Nix in particular. To see this, first replace "Nix" with "Brand X" and note that the complaints are generic to any community-developed software which doesn't have B2B resellers. Then, consider your own experience learning Nix, and note that usability, poor documentation, and a feeling that things are deliberately cryptic are all common to learning any new tool or programming language.
We can comfortably conclude that Nix did not prevent itself from being adopted by the parent's organization. Indeed, it would seem that Nix made itself extremely attractive and adoptable, else it would not have been under consideration!
I don't think Nix works for a lot of organizations as a package manager. It works for a lot of individuals for a different use case (NixOS). If you're mostly installing existing packages from nixpkgs onto a NixOS box, that probably works very well--users don't need to know much about the expression language or the nature of their dependency tree. If you're using it as a development tool, users are going to need to intimately understand Nix, its expression language, and their entire dependency tree. Further, how well Nix works for your development use case largely depends on which language you're using, how well that language is supported by Nix (is it compiled or interpreted, does nixpkgs have good coverage for your language's ecosystem, etc). Notably, working with Haskell or Go in Nix is probably quite easy, while working with Python is quite hard.
As an example, I recall trying to build a package for psycopg2 (it wasn't in nixpkgs at the time, and even if it were, for one reason or another we couldn't directly use many packages from nixpkgs), the most popular Python library for interacting with a Postgres database; however, that required me to write packages for a bunch of C libraries that I didn't understand at all, including fishing random header files out of the Postgres source code. No one in our organization including our Nix veterans could figure out how to build it correctly, and it ultimately caused us to move away from Nix (it was among the last straws).
Besides, just because it didn't work for us doesn't imply that there's a problem with our personnel (by several industry key metrics, our devops capability is excellent), but rather that the effort required to implement Nix successfully was greater than the work required to use other tooling. We could use C++ instead of Python for our organization, but just because we don't doesn't imply that our organization is incompetent; rather that Python's tradeoffs are more appropriate for our problems. In effect, Nix creates more problems than it solves for us, which is unfortunate because the problems it solves are really important problems, and many of the problems it creates are utterly unnecessary (add docstrings, use a more familiar expression language--maybe Starlark [https://go.starlark.net], provide and document 'escape hatches' so users can use system dependencies where it's prohibitively difficult to hermetically package things, etc).
Nix has a way of exposing complex and low-quality build systems. Many pieces of the Python ecosystem fall into this category. For example, it wasn't Nix's fault that psycopg2 had a dependency on postgresql C header files, nor was it Nix's fault that the postgresql headers had to be rearranged for psycopg2's build to work. Nix basically reveals the full complexity of the package's actual build environment, and for some packages the work required to make a reliable build is overwhelming. Some easier to use systems have people doing this work for you, like the Debian project. Others rely on luck to supply dependencies. The thousands of Dockerfiles that run "apt-get update" are a great example of this.
After using Nix for a while you start to reflexively shy away from software with low-quality build systems. Nix is not easy to use, but it's best of breed in terms of software supply chain auditability and malleability (anything in the system can be trivially modified or patched). If you can move to an "easy" system, that may be the appropriate trade-off for you, but it means you may be in a domain where these properties are unimportant.
Read your way down this thread and note that every defence of Nix is merely shifting the blame in it's entirety to some other part of the ecosystem. Rightly or wrongly that's a big problem for Nix if it intends to gain widespread acceptance.
It's true somewhat though, but it's a problem is not easy to solve for Python.
The problem is that Python supports C extensions, and for example the psycopg2 package has an extra dependency on a libpq which it expects to have installed on the system i.e. if you were using a docker you would do something like yum install postgresql-devel otherwise it will fail. Python won't install it for you and it doesn't even have a way to relay (except for error message) that such package is needed.
Many people actually get stuck with this and won't know what to do, but quick google show that package is needed they install and everything works. Nix is functional and doesn't have state so you can't just invoke nix-env -i postgresql and now everything will start to work, that behavior would actually ruin reproducibility. Nix instead expects that the C dependency is also provided otherwise it will refuse the build.
That's what OP meant where he said Nix exposes weak build systems.
Anyway, there was significant progress in making things better in python, it is still not awesome, but it is very close. Actually the biggest pain point right now is to setup a build environment that's convenient to use.
It uses pip2nix and it can automatically figure out all python dependencies, the packages like psycopg2 need an additional entry like this: https://github.com/takeda/example_python_project/blob/master... because PyPI packages don't specify any system dependencies.
Almost every language build system ecosystem does someting quite wrong---it's irked me for a while. I hope to within the next year or two find the time/budget to pick one language and make it work properly, and integrate with Nix perfectly.
I think not everything knows what they are missing, and by doing one complete demo we'll be able to raise the bar and give the other languages a good jolt.
It's not Nix's fault, but that doesn't make it cheaper to deal with. Whatever you want to say, `pip install psycopg2` just works because someone else already dealt with the packaging problem.
That's the cost of full reproducibility though. If Nix would not expect the postgresql package listed in dependencies and instead relied on what's currently installed on your system we would get to the starting point. Where something works on one person's computer but doesn't on another.
Yes it is harder, but if you incorporate nix definitions in your source code (you need to pin nixpkgs though) then everyone will get exact same versions of the packages and your code works on everyone's computer.
There are other ways to get enough reproducibility without the headaches of Nix, however, so that’s what we ended up doing. Reproducibility is nice, but if we need to be able to develop software quickly and for the time being, Nix is an impediment. As previously mentioned, this doesn’t have to be the case; it’s mostly an artifact of lack of documentation and a strong preference for the novel and unfamiliar over the familiar, but also for lack of escape hatches.
If you don't specify essential dependency and rely on the dependency to be installed that by definition is not reproducible.
The fix in Nix for psycopg2 is specify that it also depends on postgresql, and that's all what's needed.
Here's definition of psycopg2 from NixPkgs: https://github.com/NixOS/nixpkgs/blob/master/pkgs/developmen... (the highlighted part is the only thing that's needed everything else is just informational, doCheck is to control whether unit tests should be run during build and disabled = isPyPy tells that psycopg2 doesn't work with PyPy, which it doesn't work with, because PyPy doesn't support C extensions)
If you use direnv + lorri you just need to enter directory (if not just type nix-shell) and suddenly you have everything you need and the application is installed (try executing "hello" which will execute the python code, if you modify hello.py it immediately takes effect as if you were using "pip -e")
If you call "nix build" you'll get a result directory with "result/bin/hello" that just works as if it was a binary program (don't need to worry about dependencies)
I think nix needs a tooling that does all of the ground work of setting up dev environment for the most popular languages, because it gets really confusing.
I think you are too confident about Nix's usability.
I maintain a few open source projects. I have made packages for Redhat, Ubuntu and Arch and updated one Nix package. I love the idea of Nix, but have quit trying to support it and have removed myself as a maintainer.
Moreover, there are lots of folks having professional success with Nix, and having consumed enough of their stories, I think that the stumbling blocks that the parent identified are faults of their organization and not of Nix in particular. To see this, first replace "Nix" with "Brand X" and note that the complaints are generic to any community-developed software which doesn't have B2B resellers. Then, consider your own experience learning Nix, and note that usability, poor documentation, and a feeling that things are deliberately cryptic are all common to learning any new tool or programming language.
We can comfortably conclude that Nix did not prevent itself from being adopted by the parent's organization. Indeed, it would seem that Nix made itself extremely attractive and adoptable, else it would not have been under consideration!