The patch hashes are currently base64-encodings of the SHA2-512 of the patch as written in binary.
This is not optimal, especially when we need to copy-paste hashes (which does not happen very often for me).
I was thinking of transitionning to base58. Since Pijul 0.8 only supports SHA2-512 hashes, this can be made backwards compatible (looking at the length of the encoded hash is enough to know the encoding).
However, this is not forward-compatible: current versions of Pijul will be in trouble when the hash function is changed in the future.
Alternatively, we can drop support for base64, and release a small conversion tool. What do you think?