Library user ambiguity

When talking about the ’user’ when discussing the implementation of library software, or any programming tool, there’s an ambiguity. You could mean the end-user, the person who will be using the software which is written with the library, or the using programmer, the person writing that software. We have ’end-user’ as a good term for the former, but there’s still no good, unambiguous term for the latter. ’Using programmer’ is clumsy.