What are some alternatives?
When comparing altHUB and Cardigann, you can also consider the following products
NZBClub - NZBClub index Usenet automatically almost real-time and make it available for NZB search.
drunkenslug.com - Usenet indexer providing SSL and integration for Couch Potato, Sonarr, Sabnzd and more.
NZBHydra2 - NZBHydra2 is a meta search for NZB indexers.
NZBgeek - A Usenet newsgroups NZB Indexer.
Usenet-Crawler - Usenet-Crawler is a usenet indexing site helping you to quickly download nzbs.
Jackett - API Support for your favorite torrent trackers.