While this isn't the normal sort of product you usually find on Appsumo (since there's an element of DIY that most buyers tend to avoid, preferring lots of hand-holding), you shouldn't miss out on this opportunity..

This isn't a SaaS product - this is a headless CMS system where you are hosting a robust platform capable of all type of functionality.

You can run a website, set up a community or social media platform. You can host integrated voice and video calls, you can deliver courses, and you can wrap any and all of these up in a membership framework where you sell access, content, or any other things you can think of.

And the best part about it is that everything is powered by a powerful drag and drop design interface. Don't like how your classes are displayed along the top of the screen? No problem! Create a side bar and move them there... all the assets automatically resize themselves and format to take up the space with any other elements that previously existed.