absinthe diamond dependencies

diamond_deps.ex

defmodule CoreTypes do
  object :user do
    field :id, :id
    field :name, :string
  end
  
  object :product do
    field :id, :id
    field :author, :user
  end
end

defmodule SearchTypes do
  import_types CoreTypes
  object :search_result do
    field :query, :string
    field :results, list_of(:product)
  end
end

defmodule FeatureTypes do
  import_types CoreTypes
  object :feature_flag do
    field :creator, :user
    field :name, :string
  end
end

defmodule Schema do
  import_types SearchTypes
  import_types FeatureTypes
  query do
    ...
  end
end

Try this:

defmodule CoreTypes do
  use Absinthe.Schema.Notation

  object :user do
    field :id, :id
    field :name, :string
  end
  
  object :product do
    field :id, :id
    field :author, :user
  end
end

defmodule SearchTypes do
  use Absinthe.Schema.Notation

  object :search_result do
    field :query, :string
    field :results, list_of(:product)
  end

end

defmodule FeatureTypes do
  use Absinthe.Schema.Notation

  object :feature_flag do
    field :creator, :user
    field :name, :string
  end

end

defmodule Schema do
  use Absinthe.Schema

  import_types CoreTypes
  import_types SearchTypes
  import_types FeatureTypes

  query do
    field :hello, :string do
      resolve fn
        _, _, _ ->
          {:ok, "Hello"}
      end
    end
  end

end