cl-babel binary package in Ubuntu Focal amd64

 Babel is a charset encoding/decoding library, not unlike GNU libiconv, but
 completely written in Common Lisp.
 .
 It strives to achieve decent performance. To that effect, it uses OpenMCL's
 approach of calculating the destination buffer size in advance. Most of the
 encoding/decoding algorithms have been adapted from OpenMCL's source.
 .
 Another important goal is reusability. Similarly to SBCL, it defines an
 interface wherein the algorithms can be reused between a variety of data types
 so long we're dealing with conversions between octets and unicode code points.
 .
 Babel comes with converters between strings and (unsigned-byte 8) vectors but
 can be easily extended to deal with, e.g., strings and foreign memory, vectors
 and Closure's runes, etc...

Source package