I'd only add one more point to this otherwise excellent list of advice for programmers doing it for the long haul: 13. Strive to become as proficient as you ca

I'd only add one more point to this otherwise excellent list of advice for programmers doing it for the long haul: 13. Strive to become as proficient as you can in the business domain in which you ply your programming. Such proficiency can be a crucial asset if you have plans to start your own consultancy or to produce specialised products and solutions for niche markets.