+1

Adding two subtle points:

>> Indeed a developer owns copyright over the source code and on the compiled binaries, because there is no expansion happening here but just a translation from one format into another ... does not rely on a mountain of other IP

... and, the license agreement of the compiler and libraries used / linked to practically always explicitly waive copyrights over the said non-mountain of IP.

>> As soon as you can prove that your contribution substantially outweighs the amount of IP contributed in total you would have a much stronger case.

... a much stronger case that you have a partial copyright over the work, which is now likely a derivative work. You still may not have a case that you own the copyright exclusively (or as the original article says, that your employer does).