Impure deployement with sops-nix

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1

Hi,

I use colmena with flakes and sops-nix and I need the use of --impure option to build because of this line in my configuration.nix :

sops.age.sshKeyPaths = [ /etc/ssh/id_key];
# or
#sops.age.keyFile =  /path/to/age/key.txt

Is this the normal behavior or is there a problem in my configuration ?

Thanks