Yep, I wrote both. The difference is that letsencrypt-nosudo doesn't have access to your private user account key, so you need to manually sign the requests. Acme-tiny does have access to your private user account key, so it signs the requests for you.

I was getting a lot of requests to automate letsencrypt-nosudo, so I did with this client rather than starting to ask for private keys in letsencrypt-nosudo.

From the same author.