Ability to apply rules to external schema

Is there a trick to making rules work when a rule path refers to a key in re-used schema?

AddressSchema = Dry::Schema.Params do
  required(:country).value(:string)
  required(:zipcode).value(:string)
  required(:street).value(:string)
end

ContactSchema = Dry::Schema.Params do
  required(:email).value(:string) 
  required(:mobile).value(:string)
end

class NewUserContract < Dry::Validation::Contract
  params(AddressSchema, ContactSchema) do
    required(:name).value(:string)
    required(:age).value(:integer) 
  end

  rule(:country) { key.failure('must be foo') unless value != 'foo' }
end

If I do something similar to above, I get a Dry::Validation::InvalidKeysError stating that the rule specifies keys that are not found in schema.

This is a bug. Please report.

Will do!