More than a decade on from the financial crisis, regulators are spooked once again that some companies at the heart of the financial system are too big to fail. But they're not banks.
This time it's the tech giants including Google, Amazon and Microsoft that host a growing mass of bank, insurance and market operations on their vast cloud internet platforms that are keeping watchdogs awake at night.
Central bank sources said the speed and scale at which financial institutions are moving critical operations such as payment systems and online banking to the cloud constituted a step change in potential risks.