> Chez Scheme shoud be in between

? The default implementation as of Racket version 8.0 uses Chez Scheme as its core compiler and runtime system.

https://docs.racket-lang.org/reference/implementations.html

> some C programs use very advanced low level tricks

* possible hand-written vector instructions or "unsafe" or naked ffi" are flagged

https://benchmarksgame-team.pages.debian.net/benchmarksgame/...