acme.sh
On my servers I use amce.sh as client for Let's Encrypt. It's a "simple" bash script with no real dependencies except openssl and curl/wget - so pretty much everywhere usable.... syntax is very simple and it also supports dns-01 (if you have a supported dns provider).
The certs issued I use for apache, postfix, dovecot, syncthing and other services. They work really fine.
Biting the hand that feeds IT
