ZNC

ZNC is an IRC bouncer: it stays connected to IRC networks so clients can disconnect without missing messages or losing the session.

Note: This page concerns NixOS 19.03 and later.

Start with the following:

services.znc = {
  enable = true;
  mutable = false; # Overwrite configuration set by ZNC from the web and chat interfaces.
  useLegacyConfig = false; # Turn off services.znc.confOptions and their defaults.
  openFirewall = true; # ZNC uses TCP port 5000 by default.
};

And use services.znc.config to configure ZNC as described in Configuration on the ZNC wiki.

Clients

Choose a password, and extract a hash with:

$ nix-shell --packages znc --command "znc --makepass"

Then, in configuration.nix:

services.znc.config = {
  LoadModule = [ "adminlog" ]; # Write access logs to ~znc/moddata/adminlog/znc.log. 
  User.bob = {
    Admin = true;
    Pass.password = {
      Method = "sha256"; # Fill out this section
      Hash = "...";      # with the generated hash.
      Salt = "...";
    };
  };
};

SSL is enabled by default and a self-signed certificate is generated to ~znc/znc.pem. A fingerprint can be extracted with:

cat ~znc/znc.pem | openssl x509 -sha512 -fingerprint -noout | tr -d ':' | tr 'A-Z' 'a-z' | cut -d = -f 2

Next, see Connecting and Category:Clients on the ZNC wiki.

Networks

SASL authentication is not yet supported from configuration.nix. Either /msg *sasl or use NickServ instead as shown below.

service.znc.config.User.bob = {
  Network.freenode = {
    Server = "chat.freenode.net +6697";
    Chan = { "#nixos" = {}; "#nixos-wiki" = {}; };
    Nick = "bob";                             # Supply your password as an argument
    LoadModule = [ "nickserv yourpassword" ]; # <- to the nickserv module here.
    JoinDelay = 2; # Avoid joining channels before authenticating.
  };
};