[sowbug]

Don't use the term "retirement." Instead, you're doing a solo startup. Add that it's in stealth mode if you don't feel like talking about your current focus of attention. If I'm reading your comment correctly, it's not even a lie; it sounds like you'd be happy turning a hobby into a business if that's where fate took you.

I "retired" about a year ago after almost 25 years in the industry. My story since then is a lot like that of the author of the article. I've written more code this year for love than I bet I did in 10 years for pay. It's been exactly the retirement I wanted: one of the most productive times of my life.