I met a guy travelling in South Africa / Namibia in 2013 who had two web businesses (https://www.replacementkeys.co.uk/ and InternetRadio.com). Had No Degree, just self taught / on the job training. He had written most of his stuff in Perl :o! Similar philosophy to this to Pieter Levels!
The other story which is very inspiring as well is the Tailwind CSS (https://adamwathan.me/tailwindcss-from-side-project-byproduc...)