Security of Julia, since possible to change the compiler at runtime

Continuing the discussion from This month in Julia World - 2026-08: Slide 48 Not too surprising. If you have access to the compiler (or infrastructure), then you can change the generated code: We can already change the parser at runtime. I believe we can also change the compiler in arbitrary ways. E.g. a package could? Is there any way around this in Julia or languages like Lisp? Even Python? Can and should the compiler be code that is is a separate process? An .so/.dll? could you still un...