Dear David, The bug report [1] opened more than 4 years ago about the Chicken bootstrapping is still pending. I am not sure to understand these lines; quoting you [1]: << Generated from optimizer.scm by the CHICKEN compiler This is *not* source code, it's a binary disguised as C source code. >> Why is it an issue for bootstrappability? Thank you in advance for any comments. Or could this bug report be closed? All the best, simon [1] https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22366