I landed a contract to develop a saas system before I really knew how to program for the web, I had some prior systems programming experience but had not coded

I landed a contract to develop a saas system before I really knew how to program for the web, I had some prior systems programming experience but had not coded for about 5 years. I quit my job to develop it and delivered but was never able to land another customer. I still have the original client 3 years later and the company grosses about $3,500 per month and I net $1,250. It pretty much runs itself, requires maybe 2 hours of work every 2 - 3 months. I spent a little over a year trying to grow it from the initial customer with no luck. Landed a job as a full stack engineer afterwards and I really like it. I am actively looking to start a new project but I will keep my main job while doing it. I had the benefit of a wife who makes a good salary to support me during that prior adventure (Still do :) )