The bpycv package is incompatible with blender version 4 or later. It seems that neither upstream author nor the nixpkgs maintainer are currently interested in updating/maintaining this package. See: - https://github.com/NixOS/nixpkgs/issues/379872 - https://github.com/DIYer22/bpycv/issues/51 - https://github.com/NixOS/nixpkgs/pull/380403 - https://github.com/NixOS/nixpkgs/pull/380443