Install cl-base64 by entering the following commands in the terminal:
sudo apt update sudo apt install cl-base64
Description:
Common Lisp package to encode and decode base64 with URI support
This package provides highly optimized base64 encoding and decoding. Besides conversion to and from strings, integer conversions are supported. Encoding with Uniform Resource Identifiers is supported by using a modified encoding table that uses only URI-compatible characters.
Homepage: http://files.kpe.io/cl-base64/
Version: 3.3.4-1
Section: universe/devel