Being a full-stack developer means to have an open mind towards new technologies, having your hands dirty in each one and to have an understanding of how a web application gets done from a concept to design to the finished product.
The idea of a “full-stack developer” isn’t about being fluent in every possible technology there is, because specialization exists for a reason. It’s more about having an understanding in each of the areas above, to communicate intelligently between team members and to be a good asset if the situation needs it.
The full-stack developer will have an increasingly important role in the web development of the future, especially when development methods such as DevOps are becoming an essential part of software development companies, where the line between code developers and administrators who are responsible for code deployment and setup is getting thinner each day.