I use Lisp for my projects

1. Type checking built in 2. More concise and readable than most languages 3. Trivial to inspect while running, ability to change a running program 4. There seems to be a massive amount of lisp that it is inhaling from somewhere 5. Large amount of libraries.

This has the added benefit that even if you publish the code, nobody will be stealing it.

Edit -- I find it very useful to write tests for critical functions. This catches situations where the agent decides some interesting functionality is no longer interesting.