I can't imagine throwing a developer who has 10 years of solid Java or C# experience at a project in LISP and expect good results in a short period of time. I haven't been a C# developer in a bit more than 10 years, and looking at modern C# is a world of difference, it's moved so much in the direction of a functional paradigm, added a pile of new operators that fundamentally change how people write code... it would be like Shakespeare trying to read and write English in 2022...

J.Ja