I think I'm too cynical to do these kinds of side businesses... I look at this and am confused why anyone is paying for it. I often find it hard to step away from what I would do compared to what others will do.
Well what’s the alternative to taking good notes for a developer? Markdown on git? You still have to pay for github if you want it to be private and you have the hassle of setting it up. $5/month is irrelevant if you use it a couple of times a day
I've been using StackEdit.
> You still have to pay for github if you want it to be private
You can upload to a Gist and set it private