By the way, one of NNCP users send me a (personal) message:

>NixOS supports merging of configuration values and files using nncp-cfgdir. The same technique might be useful for Ansible and Puppet.
>https://nixos.wiki/wiki/NNCP
>https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/programs/nncp.nix#L72

So nncp-cfgdir is already used by someone more actively than me :-)

-- 
Sergey Matveev (http://www.stargrave.org/)
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