Even though the question was sufficiently answered in the end, I want to add something to answer the original answer for other people with the same question. In openfhe-python you can indeed serialize a Ciphertext (and more openfhe objects like keys) to a string, following the example/test found here. These methods that avoid writing to a file (and thus to disk), could be much faster and can be used in other cases that require sharing serialized openfhe objects like multiprocessing (link a related question here).