Serverless 1 deprecation triggered:

[Bonafede]

When you try to run the serverless command this message appear

1 deprecation triggered in the last command:

CLI options definitions were upgraded with "type" property (which could be one of "string", "boolean", "multiple"). Below listed plugins do not predefine type for introduced options:
 - ServerlessWebpack for "out"

Probably it comes with the webpack custom.