I have extended babel with a new character encoding, but it's not clear to me what is the right way to compile the newly defined encodings and make them visible visible to babel's octets-to-string, etc. So far I have resorted to the following (copied from babel's strings.lisp): (defparameter babel::*string-vector-mappings* (babel-encodings:instantiate-concrete-mappings :octet-seq-setter babel::ub-set :octet-seq-getter babel::ub-get :octet-seq-type (simple-array (unsigned-byte 8) (*)) :code-point-seq-setter babel::string-set :code-point-seq-getter babel::string-get :code-point-seq-type babel:simple-unicode-string)) Is there a better way? Vebjorn