NZBHydra 2 is a meta search for NZB indexers.
It provides easy access to a number of raw and newznab based indexers.
You can search all your indexers from one place and use it as an indexer source for tools like Sonarr, Radarr or CouchPotato.
There is a wrapper that is required to run the program, which is in the files/ directory and updated dynamically.
I'm unsure about the ordering, so please let me know if it's out of order.