Sign the dist as the last step before creating the archive. Take care not to modify/regenerate dist meta files or the manifest.

Error: Old SIGNATURE detected. Please inform the module author to regenerate SIGNATURE using Module::Signature version 0.82 or newer. gpg: Signature made Fri 18 Sep 2015 09:54:06 PM JST gpg: using RSA key 97BE5D729A22E4E5 gpg: Can't check signature: No public key ==> BAD/TAMPERED signature detected! <==

Add a META.json to the distribution. Your buildtool should be able to autogenerate it.

Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.

This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.