Usually there are two skills to have to ship a software project: - Knowing and using the basic underlying technologies (languages, but also concepts, like mach

Usually there are two skills to have to ship a software project: - Knowing and using the basic underlying technologies (languages, but also concepts, like machine learning, databases, UI skills or so on) - Knowing the specific codebase and process for those projects (how the build works, what are the components, what they do, etc). True, someone knowing the first skillset has an advantage, but a talented person will have no problem doing the second one much faster. For an hire, I would rather factor in the long term. It's about sane finance management and ROI, actually. For any given pool of candidates, you are considerably reducing the chance you hit a talented people, if you interview only 10% of all candidates just based on their previous base skills.