Pure speculation on my part (since I couldn't find any details either): their "Closed world assumption" and "No reflection" principles [1] could mean the compil

Pure speculation on my part (since I couldn't find any details either): their "Closed world assumption" and "No reflection" principles [1] could mean the compiler can output radically different bytecode, e.g., eliminating the tail call by eliminating the "call" altogether. That said, I might be wrong given that the FAQ [2] notes that tail call elimination "has some run-time performance cost"; maybe they're baking in a trampoline. [1] https://flix.dev/principles/ https://flix.dev/principles/ [2] https://flix.dev/faq/ https://flix.dev/faq/