The classic MIT Scheme
Have you ever seen the iconic lectures at HP by Abelson and Sussman? https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-001-structure-and-interpretation-of-computer-programs-spring-2005/video-lectures/
This is the very same MIT Scheme. You should literally feel like touching something sacred.
git clone git://git.savannah.gnu.org/mit-scheme.git cd mit-scheme/src ./Setup.sh ; ./configure --prefix=/usr/local ; make -s all sudo make -s install