The stack developer meaning can get muddled as it is typically used for the stack of technologies that an application is constructed from. A development stack can consist of programming language, front-end framework, back-end technology, database and other tools. A “stack developer” is typically a developer that uses a certain technology stack. Activities vary depending on the stack and project. The key is to get to know the technology and not the label, particularly if assessing a developer's skills or when deciding what to learn.