These instructions are for implementing HTTPS on a NFSN-hosted static site using a certificate from Let's Encrypt. The certificate is generated manually on a separate computer.
Start off by installing the letsencrypt client. This requires sudo privileges and will install a bunch of packages:
% curl -O https://dl.eff.org/certbot-auto
% chmod +x ./certbot-auto
% ./certbot-auto
Generate the certificate. This will require you to publish some challenge responses on NFSN. I find it easiest to use tmux with letsencrypt running in one window and an SSH session to NFSN in another:
