Problem
Git defines two remote modes with authentication: ssh and https. Through tools.gitlibs we support ssh auth via a connection to an ssh-agent. git+https authentication is not currently supported, though common in the wild.

Workarounds
Use git over ssh, for now.

Background info
The mainline git implementation supports a mechanism named "credential helpers" through which it demands authentication from an oracle. These helper oracles are executables invoked with a map of authentication demand (arriving via stdin) and they return authentication information (over stdout):

This extension mechanism allows integrations with 1Password, LastPass, and Hashicorp Vault. By default git config --get 'credential.helper' returns osxkeychain on macOS and cache on Linux. git resolves credential helpers either by absolute path + args or like so:

Authors of credential helpers should make an effort to assist their users by naming their program "git-credential-$NAME", and putting it in the $PATH or $GIT_EXEC_PATH during installation

git also supports configuring defaults for usernames or credential helpers by looking up URLs in its config.

JGit, used by tools.gitlibs, supports the idea of a CredentialProvider with several concrete implementations (AwtCredentialsProvider, ChainingCredentialsProvider, ConsoleCredentialsProvider, NetRCCredentialsProvider, UsernamePasswordCredentialsProvider) but none that work the same way as mainline git.

Github currently prefers https over ssh for git access (though that has historically flip-flopped).

Non-starters

• Putting credentials in deps.edn