Some time ago, Let's Encrypt announced that they will be supporting ACME v2 on February 27, 2018. I'm already busy implementing ACME v2 support in Hiawatha's Let's Encrypt client. It's almost finished. There are just some small issues to fix, but those might be a server-side bug as well.
Another new Let's Encrypt feature that's coming in February 2018, is support for wildcard certificates. The issue is that they can only be obtained via a DNS challenge instead of via the HTTP challenge I'm currently using. Using a DNS API is not an option, because not every DNS provider offers an API for DNS changes and there is also no single standard for such API. At the moment, I'm discussing my idea about how to obtain a wildcard certificate via an HTTP challenge with Let's Encrypt and the ACME Working Group at IETF. Hopefully they accept my idea.
Anyone who wants the try the new version of Hiawatha's new Let's Encrypt client, you can download it here.