Does Coding in CMS makes you unprofessional?

When you say “coding in CMS”, I'm assuming that you were talking about making plugin/theme for CMS or develop applications based on CMS ?

Regard that question, I would say no. CMS(s) have their own market, which could help you earn well. But I think you should consider the followings:

• You should know your tool well: understand its pros/cons or what are the best practices. Wordpress is the most popular CMS ever, but it has the bad source code with lot of hack/magic and is bashed by the PHP community a lot.
• Don't limit your knowledge in the CMS area only. Learn other systems/frameworks/languages. That helps you be a better programmer. (I went from Joomla > Wordpress > Magento > Zend 1 > Laravel > Symfony and now I'm working with Python/Go.)

An honest review would be very helpful.

Thanks.