ACME nsupdate 
ACME (Let's Encrypt) client with nsupdate (DDNS) integration.
CLI tool to obtain certificates via ACME and update the matching TLSA records. The primary authentication method is http-01 via webroot for now, but dns-01 is supported too.
Don't actually trust this, I wrote it for myself. Read and understand the code if you want to actually use it. There are no tests!
Installation
Install the gem:
$ gem install acme_nsupdate
Usage
See the help:
$ acme_nsupdate --help
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/jhass/acme_nsupdate. Feature contributions are welcome too, feature requests will most likely not be fulfilled.
License
The gem is available as open source under the terms of the MIT License.