Change:
hash = "sha256-idVklxLIWCIxxuEYJaBMhfbwzulNu4nk2yPqvKHMJQo="; }; <ins> patches = [ # https://github.com/SciTools/cartopy/pull/2163 (fetchpatch { url = "https://github.com/SciTools/cartopy/commit/7fb57e294914dbda0ebe8caaeac4deffe5e71639.patch"; hash = "sha256-qc14q+v2IMC+1NQ+OqLjUfJA3Sr5txniqS7CTQ6c7LI="; }) # https://github.com/SciTools/cartopy/pull/2130 (fetchpatch { url = "https://github.com/SciTools/cartopy/commit/6b4572ba1a8a877f28e25dfe9559c14b7a565958.patch"; hash = "sha256-0u6VJMrvoD9bRLHiQV4HQCKDyWEb9dDS2A3rjm6uqYw="; }) ]; </ins> nativeBuildInputs = [ cython geos # for geos-config

Discussion:
Steps to reproduce the behavior: I'm running nix under the available docker image. <!-- --Please run and paste the result.
I can confirm build failure inside docker image this has been fixed in latest nixpkgs run and try again
I've also noticed I get rather frequent crashes from inside docker, not sure what thats about, but it builds outside of docker
Thank you! I'll try it with the new docker image tomorrow. Yeah, Docker seems to create some issues, I'm not certain why.
I'm sorry I couldn't test this until today. After updating with inside the docker container, and doing , I got a different error:
yes, looks like cartopy is broke again on master while I am bisecting to find why it failed, to hopefully come up with a fix python 3.9 is no longer built in hydra so there will be no pre compiled binaries coming , if you can, switch to 3.10 and 3.11 while nixos/nix docker image works fine in most cases, I tend not to use it due to: disabled sandox and difficulty of setting up local caching building docker images locally outside of docker using nix seems to work much better, although has own disadvantages What specifically are you trying to do ? since we know a very recent good commit hash for nixpkgs that has working cartopy we can build a docker image using nix.
Thank you for dealing with this, I really appreciate it. I'm working on a project where I need to install a combination of some older libraries of Fortran (gfortran-8), C++, and several specific Python libraries too. The Fortran libraries are not available in the latest versions of Ubuntu, and probably not in the latest versions of macOS. Nix is a great solution to make an ad-hoc environment that I could export and share for cross-platform use. This is especially important for research, as you want to be able to share your results and the tools to reproduce your results with other scientists. Currently, I'm using Docker because the computing center I have access to doesn't have the Fortran libraries I need, so I managed to have access to Docker, where I can use the nixos/nix image and therefore satisfy the dependencies of this project. Not ideal, but works as long as I don't use cartopy 3.9.

I'll see how it goes with newer Python libraries too, but I'd rather keep the wheels running with what I have. I'm quite new with nix, so I'm learning my way to make a reproducible environment. For now, I've managed to install the libraries I need, which is just wonderful. Later, I want to make this environment properly reproducible and share the steps with other researchers, so it's easier for them to just install nix and then set up the project and let it calculate things.
python 3.9 should work fine, you just need to compile more dependencies nix-env -i is only useful for packages that provide executables, eg has files in ./bin. I can see that cartopy has . you wont be able to import cartopy via if you want enviroment where you can import cartopy you can use something like this meanwhile we'll keep this issue open, until cartopy is fixed on master
sorry i just realised you want python3.9