I dived into the hex.pm (Erlang package manager) ecosystem and found that we can list it like this:

• Iterate through the package API https://hex.pm/api/packages/ (pass ?page=n for pagination)
• To get a list of released versions for each pkg, extract pkg["releases"][i]["version"] where i is the ith release.
• Now combine these versions with the package name in based on the format: https://repo.hex.pm/tarballs/{pkg_name}-{pkg_version}.tar
• Send these urls to the tar loader along with extra metadata.
• For the last_update value, we can use pkg["updated_at"]

Sample tar link: https://repo.hex.pm/tarballs/jason-1.4.0.tar

References:

• Hex.pm specs
• Hex CLI source code
• Hex.pm source code