add core configuration

modules/fileshare/default.nix

@@ -0,0 +1,17 @@
+{lib, ...}: let
+  # recursively construct attr-set of a directory
+  getDir = dir:
+    lib.mapAttrs (file: type:
+      if type == "directory"
+      then getDir "${dir}/${file}"
+      else type) (
+      builtins.readDir dir
+    );
+  files = dir: lib.collect lib.isString (lib.mapAttrsRecursive (path: type: lib.concatStringsSep "/" path) (getDir dir));
+  validFiles = dir:
+    map (file: ./. + "/${file}") (
+      lib.filter (file: lib.hasSuffix ".nix" file && file != "default.nix") (files dir)
+    );
+in {
+  imports = validFiles ./.;
+}

modules/fileshare/samba.nix

@@ -0,0 +1,55 @@
+{
+  config,
+  lib,
+  ...
+}: let
+  cfg = config.lily.fileshare;
+in {
+  options.lily.fileshare.enable = lib.mkEnableOption "activate local filesharing";
+
+  config = lib.mkIf cfg.enable {
+    services.samba = {
+      enable = true;
+      securityType = "user"; #Keep user, but use guest account.
+      openFirewall = true;
+      settings = {
+        global = {
+          workgroup = "WORKGROUP"; #Ensure this matches your network's workgroup.
+          "server string" = "smbnix";
+          "netbios name" = "smbnix";
+          "security" = "user"; #Keep this as user, but guest will be used for access.
+          "hosts allow" = "192.168.1. 127.0.0.1 localhost"; #Adjust to your LAN.
+          "hosts deny" = "0.0.0.0/0";
+          "guest account" = "nobody"; #Important for guest access.
+          "map to guest" = "bad user"; #Maps unknown users to guest.
+        };
+        "public" = {
+          "path" = "/ext/share";
+          "browseable" = "yes";
+          "read only" = "no";
+          "guest ok" = "yes"; #Allows guest access.
+          "create mask" = "0644";
+          "directory mask" = "0755";
+        };
+      };
+    };
+
+    services.samba-wsdd = {
+      enable = true;
+      openFirewall = true;
+    };
+    services.avahi = {
+      enable = true;
+      nssmdns = true;
+      nssmdns4 = true;
+      openFirewall = true;
+      reflector = true;
+      publish = {
+        domain = true;
+        enable = true;
+        userServices = true;
+        addresses = true;
+      };
+    };
+  };
+}