function init/1 required by behaviour ConsumerSupervisor is not implemented

[Former user]

Using Belt 0.4.2, I get the following warnings:

==> belt
Compiling 18 files (.ex)
warning: function init/1 required by behaviour ConsumerSupervisor is not implemented (in module Belt.Provider.Filesystem.Supervisor)
  lib/belt/provider/filesystem.ex:7: Belt.Provider.Filesystem.Supervisor (module)

warning: function init/1 required by behaviour ConsumerSupervisor is not implemented (in module Belt.Provider.SFTP.Supervisor)
  lib/belt/provider/sftp.ex:3: Belt.Provider.SFTP.Supervisor (module)

Generated belt app

I'm not (yet!) using S3, which explains the lack of warning for that provider.

Let me know if I can help with anything!