I am now a retired architect, who had his own practice, but have been involved with writing code for AutoCAD since Rel9, as well as chairing the UK BS1192 Part5 Layering Group.
I am writing a large management application in VB.NET.
I have coded about 90%,and debugged 50%.
Still much interesting stuff to do.
I can see that maintenance, technical support, new technologies will become more uncertain in the future as I get older, and will prevent potential clients from buying the product.
I also would like to share the adventure with others.