Git
1. Credentials
If I want to write to this repo at a different (somewhat) trusted place, I need write-access to it. Since I do not really understand how to use yubikey & gpg, I hestitate to use them, especially where I think that the repo do not have much value to whoever has access to.
So I prefer git credentials with https connection.
1.1. Plaintext store
Generate the git config, see https://git-scm.com/book/en/v2/Git-Tools-Credential-Storage for the input format.
git credential-store --file ~/some_file store
Add the following lines to my git config
[credential] helper = store –file ~/somefile