It was, I maintain a port here [0]. Release tarballs can be downloaded here [1], I plan to add them to the git tags but did not get to it yet. For example alpine linux ships it in the repositories [2].

0: https://git.sr.ht/~graywolf/acme-client-portable

1: https://data.wolfsden.cz/sources/

2: https://pkgs.alpinelinux.org/packages?name=acme-client&branc...