I updated Docker Desktop today to the latest version and it broke building images from flyctl.
I could still use the docker command from the terminal to build images etc but I got this error when trying to fly deploy --local-only:
Error: failed to fetch an image or build from source: docker is unavailable to build the deployment image
Which is weird because, again, I could build using the docker command.
I started downgrading Docker Desktop versions until (4.24.2) finally worked.
I don’t know what caused the issue with flyctl but I think the issue was caused by a new feature for managing builders in Docker Desktop.
In the latest version of Docker Desktop with the builders features, I could see the default builder had an error because it couldn’t connect with the daemon. There was a new one called desktop-linux which was working fine from the dockercommand but not from flyctl.
Maybe flyctl has a hardcoded value or something that points to the default builder?