How is it like to run SaaS company on your own? How many of you out there are making $$$ from their own SaaS business?

I have been working as a Software Engineer for quite some times now and I enjoy crafting production quality software. I am also an ex co-founder of a small digital marketing company - this is what helped me understand software products from a marketers perspective and plan things out accordingly even before starting any sort of development. All of this started off as a hobby - I always enjoyed building systems and I have always had my own side projects - recently, one of my side projects started getting a lot of attentions and traffic. I am currently working as a full time Software Engineer for a local company which leaves me tired after work. I would love to partner up with someone at some point - for now I'm just wondering how many of you out there are running SaaS all on your own? I would appreciate if you could share your experiences and provide any helpful tips on running a SaaS business independently :)