quicklisp CFFI-GROVEL:GROVEL-ERROR Couldn't execute "cc" about sketch HOT 2 CLOSED

Well, it looks like you don't have a C compiler named cc. There is probably a configuration variable to change it to something like gcc/clang/whatever, but I guess it would be easier to install it / make a symbolic link /usr/bin/cc to another C compiler.

P.S. The variable is (probably) cffi-toolchain:*cc*.
You could try

(ql:quickload :cffi-toolchain)
(setf cffi-toolchain:*cc* <name-of-c-compiler>)
(ql:quickload :sketch)

Hopefully it helps!

from sketch.

Turns out all I had to do was install gcc (cc is an alias command for it) and it worked. So yes it turned out to be a very obvious thing I was missing, thank you very much for pointing me in the right direction though!

from sketch.