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From the Chicken-users mailing list, a post by Felix.
This shows a minimal example of embedding (you don't need CHICKEN_initialize, unless you want to set specific buffer sizes):
/* gcc x.c -lchicken -o x */ int main() { C_word x; CHICKEN_run(CHICKEN_default_toplevel); CHICKEN_eval_string("(print (+ 3 4))", &x); return 0; }