It is a Django application, whose purpose is to mimic the features of a YouTube and a Twitch accounts, in terms of subscriptions, follows, and playlist management. It is open-source, more precisely developped under the MIT License. You can find the source code on GitHub.
Its purpose is the preservation of privacy without the cost of practicality, by allowing users to still follow content creators without having to rely on YouTube or Twitch recommandation system. This is a way of remaining in control of what one's see.
On desktop, it combines greatly with incognito navigation. On Android, applications such as YoutTube Vanced are fitted to be used with Notifpy. Similar applications for Twitch exist but are not advanced enough for it to be used on a regular basis. In both cases, remember to maintain an empty cache to get rid of history and recommandations.
The repository's README contains all the information you need.
Following the APIs guidelines, I can not offer this application as a public service. But if you want to have a quick look at, I can create a temporary demo account. Feel free to contact me.