Sometimes, to use certain software, some other software needs to also be installed, or the computer has to fulfill certain properties. For these kinds of conditions, the terms "requirement" and "prerequisite" are usually used. (In Python application projects, it's even customary to have a file called
requirements.txt that lists required Python packages in machine-readable form.)
Another English term that is sometimes used for this meaning (to distinguish it from the requirements you impose on the software in question (what it's supposed to do / solve — the requirements specification)) is "dependency".
Is there an Esperanto term for stuff (especially other software) a software depends on?