No signed images on Docker hub?


Trying to pull drone from dockerhub, I see this error:

$ docker pull drone/agent:1.3.1
Error: remote trust data does not exist for docker.io/drone/agent: notary.docker.io does not have trust data for docker.io/drone/agent

Are there no signed images on dockerhub?

If not, then are there instructions on how to compile drone and build containers from the git repository?