I pick a platform/language that's stable. e.g. Common Lisp. The libraries everyone use typically don't change -- you can usually get away with not even specify

I pick a platform/language that's stable. e.g. Common Lisp. The libraries everyone use typically don't change -- you can usually get away with not even specifying a version number. The language hasn't changed since being standardized decades ago. That doesn't mean its deficient -- it's a programmable programming language, thus various things that are features of other languages are just more libraries in Common Lisp.