I came across this question on Quora today and decided I would answer it. There were enough up-votes by people following the question that I’m re-posting my answer below:
I’m not sure what the term “world-class coder” means to you. But I would actively discourage the notion that there is some point you can reach in the practice of software development (whether it’s 3 years or 20 years) where you can look at yourself and say “Achievement unlocked! I am a world-class coder at last.” What may give you more satisfaction over time than the question of “where do I rank” in some mythical best coders on Earth list is “Am I a better developer now than I was last week? Last month? Last year?”
The things that previous commenters have suggested are great ideas for continuous improvement and refinement of your skills in programming. Do as many of those things as you can. Beyond those, I’d suggest the following:
Be willing to learn from anyone. I’ve made my living writing software since 1996 and I regularly learn new things about my craft from people a decade or more younger than me.
Keep track of what you learn–and share it. Whether it’s through blogging, Stack Overflow contributions, or something else–write about it. You may not encounter the exact problems you’ve solved in the future, but they will often be close enough that what you’ve captured will help you solve them much faster than you would have otherwise. The ability to explain what you know to others is a very valuable and rare one. The process of preparing to give a presentation to others on a topic has often been a good forcing function for me to learn that topic to the level where I can explain it well.
Learn about subjects beyond programming. The importance of the ability to understand new domains well enough and deeply enough to design and implement useful software for them cannot be overstated. I’ve delivered software solutions for news organizations, healthcare companies, marketing companies and defense/intelligence contractors in my career so far. Making myself familiar with the sort of terminology they use and the way such companies operate (above and beyond a specific project) definitely results in a better end product. One or more such topics can end up being great fodder for pet projects (which are great vehicles for learning things you aren’t already learning in a job).