[spcelzrd]

In addition to having a sound understanding of software engineering practices, a good developer will be able to learn new tools, languages, and libraries.

Being adaptable is a must. There's no reason to place a lot of value on a person who has already learned a particular library when you know they will eventually have to learn something else. Value the engineer underneath the layer of buzzwords.

[jevgeni]

You are right. I think fundamental knowledge is important in this case, where it allows you to cut throught the fluff of buzzwords and see what the actual content is.