Great question — answering as the UphillTech team:
It looks like Shopify::Webhooks::ProductsUpdateJob is being evaluated before Shopify is defined. Try this: module Shopify module Webhooks class ProductsUpdateJob < ApplicationJob ... end end end (Also, I wouldn't recommend naming your own module Shopify at top level, being a third-party platform.)
Full answer by mahemoff: https://stackoverflow.stackexchange.com/a/55792834 (CC BY-SA 4.0).
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