Rspamd

Rspamd is a fast, free and open-source spam filtering system.

Installation

To enable Rspamd add following line to your system configuration

/etc/nixos/configuration.nix

services.rspamd.enable = true;

Configuration

Whitelist domain

To whitelist a specific domain (in this example the domain example.org) which otherwise gets rejected by Rspamd for various reasons, this custom configuration override can be added:

/etc/nixos/configuration.nix

services.rspamd = {
  enable = true;
  overrides."whitelist.conf".text = ''
    whitelist_from {
      example.org = true;
    }
  '';
};