(creator of 3L)<p>No. Almost any language we use today can run on 3L and transpilers are planned for the future of 3L. The security features will still be provided via the underlying lisp though. Technically the same security mechanism could work for most languages but it is much simpler, easier, and more natural to implement in lisp.<p>Even languages like C can be supported safely via memory emulation (although right now that would mean it runs quite slowly but likely, although no guarantee, it will run well enough in the future as hardware becomes more powerful).