{
  config,
  lib,
  pkgs,
  self,
  ...
}: let
  postfixConfig = pkgs.writeTextFile {
    name = "main.cf";
    text = builtins.readFile ./postfix/main.cf;
  };
in {
  system.activationScripts.mkMailmanNet = let
    docker = config.virtualisation.oci-containers.backend;
    dockerBin = "${pkgs.${docker}}/bin/${docker}";
  in ''
    ${dockerBin} network inspect mailman-net >/dev/null 2>&1 || ${dockerBin} network create mailman-net --subnet 172.20.1.0/24
  '';

  users.users.mailman = {
    description = "Mailman Service";
    home = "/var/lib/mailman";
    useDefaultShell = true;
    uid = 993;
    # Group hakkonaut so caddy can serve the static files from mailman-web directly
    group = "hakkonaut";
    isSystemUser = true;
  };

  age.secrets.mailman-core-secrets = {
    file = "${self}/secrets/mailman-core-secrets.age";
    mode = "600";
    owner = "mailman";
  };

  age.secrets.mailman-web-secrets = {
    file = "${self}/secrets/mailman-web-secrets.age";
    mode = "600";
    owner = "mailman";
  };

  age.secrets.mailman-db-secrets = {
    file = "${self}/secrets/mailman-db-secrets.age";
    mode = "600";
    owner = "mailman";
  };

  virtualisation = {
    docker = {
      enable = true;
    };

    oci-containers = {
      backend = "docker";
      containers."mailman-core" = {
        image = "maxking/mailman-core:0.4";
        autoStart = true;
        user = "993";
        volumes = [
          "/var/lib/mailman/core:/opt/mailman/"
        ];
        extraOptions = [
          "--network=mailman-net"
        ];
        environment = {
          DATABASE_TYPE = "postgres";
          DATABASE_CLASS = "mailman.database.postgresql.PostgreSQLDatabase";
          MTA = "postfix";
        };
        environmentFiles = [
          config.age.secrets.mailman-core-secrets.path
        ];
        ports = [
          "127.0.0.1:8001:8001" # API
          "127.0.0.1:8024:8024" # LMTP - incoming emails
        ];
      };

      containers."mailman-web" = {
        image = "maxking/mailman-web:0.4";
        autoStart = true;
        user = "993";
        volumes = [
          "/var/lib/mailman/web:/opt/mailman-web-data"
        ];
        extraOptions = [
          "--network=mailman-net"
        ];
        environment = {
          DATABASE_TYPE = "postgres";
          SERVE_FROM_DOMAIN = "list.pub.solar";
          MAILMAN_ADMIN_USER = "admin";
          MAILMAN_ADMIN_EMAIL = "admins@pub.solar";
        };
        environmentFiles = [
          config.age.secrets.mailman-web-secrets.path
        ];
        ports = [
          "127.0.0.1:8000:8000" # HTTP
          # "127.0.0.1:8080:8080" # uwsgi
        ];
      };

      containers."mailman-db" = {
        image = "postgres:14-alpine";
        autoStart = true;
        user = "993";
        extraOptions = [
          "--network=mailman-net"
        ];
        volumes = [
          "/var/lib/mailman/database:/var/lib/postgresql/data"
        ];
        environmentFiles = [
          config.age.secrets.mailman-db-secrets.path
        ];
      };

      containers."mailman-postfix" = {
        image = "mailu/postfix:1.9.46";
        autoStart = true;
        user = "993";
        extraOptions = [
          "--network=mailman-net"
        ];
        volumes = [
          "/var/lib/mailman/postfix/overrides:/overrides:ro"
          "/var/lib/mailman/postfix/mailqueue:/var/spool/postfix"
          "/var/lib/mailman/postfix/data:/var/lib/postfix"
          "/var/lib/mailman/core:/var/lib/mailman/core"
          "${postfixConfig}/bin/main.cf:/etc/postfix/main.cf"
        ];
        environmentFiles = [
          config.age.secrets.mailman-db-secrets.path
        ];
      };
    };
  };
}