[eru]

I haven't done FFI with Racket, but https://docs.racket-lang.org/foreign/index.html looks reasonably approachable?

[umanwizard]

That seems to let you call C functions from Racket, but I don't see how it lets you embed Racket in a C program and call Racket functions from C. So it's at best half a solution, unless I'm missing something.

[eru]

See https://docs.racket-lang.org/inside/cs-procs.html