Capsul is a NixOS-friendly hosting provider. Currently, the NixOS images which Capsul is able to provision must be updated manually. Here is how Aynish did this... to quote them directly (but slightly reformatted) from Matrix:
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okay, here's what i did:


* went to releases.nixos.org and followed the web ui to the most recent release of 23.11 (highest number after nixos-...-23.11.iso)
* i clicked on the sha1 for the iso i wanted (x86_64-linux)
        https://releases.nixos.org/nixos/23.11/nixos-23.11.4248.01885a071465/nixos-minimal-23.11.4248.01885a071465-x86_64-linux.iso.sha256 it has both url and hash
* I went to https://git.cyberia.club/cyberia/capsul-images and cloned it
* I copied nixos/22.11 to nixos/23.11 with:
 ``` cp -R nixos/22.11 nixos/23.11 ```
*     I updatded system.stateVersion in configuration.nix
    and then changed the references to the new one folder in build.yarn
    in nixos/23.11/packer.json i updated references to the new iso

```
nix-shell -p packer
cd nixos
./build 23.11
```
and now I'm waiting a bunch for it to finish. Once it finishes, I'll try and boot it up in qemu and check that it works. Then I'll submit a PR
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That's the current status. Once it's been double checked, this also needs to be documented at: