Comment by dgl

GPG for sure, be very careful with "vim -x" as that's the only implementation of that encryption scheme, not supported in neovim anymore (and I've found security issues in it: https://dgl.cx/2014/10/vim-blowfish, "blowfish2" is just ok, but it's frankly still there to not break people's workflow, I would think very carefully before using it).

Annoyingly this technique uses AES-GCM (which is good!) but OpenSSL's command line tool can't cope with it: https://github.com/openssl/openssl/issues/12220

It would be nice to have a command line tool to extract these files too, then you know the implementation is correct. (Blowing my own trumpet but my very old project https://paste.sh does this.)