Hey there, I'm fsoc. I wrote maniac back in 2017, and published it in 2018. Over the years I was approached by a number of people either asking if I was providing private versions of maniac or if I was accepting donations. Until recently, I said no.
I'm still maintaining the public version on GitHub and that one will always be free for everyone. But having a private version allows me to implement features that would have otherwise taken up too much of my time to work on. These kinds of features will be exclusive to this version.
But, first and foremost this is a project I work on in my free time for fun. I hope you can have fun with it too!