I have authored one project that took ten years to reach maturity (It is now exploding). That allowed me to iterate it, and ensure that it would be top-quality, by the time I tossed the reins over to a new team.
It was free, though, and a labor of love[0].
I wrote another project as a "training course." It was sort of a dissertation. The quality is pretty much "off the charts."
I had originally thought about selling it, but was told that was a non-starter, because it was written in in PHP[1], so I simply open-sourced it as MIT.
Nowadays, I work on client-side code (native Swift for Apple stuff). I am not in a hurry to get back to SaaS.
I like the name of the blog.
[0] https://medium.com/@ChrisMarshallNY/the-story-of-the-bmlt-87...
[1] https://riftvalleysoftware.com/work/open-source-projects/#ba...