"If we are running 20 to 50 servers, that process might take two to three hours," he states.
In the Amazon environment, they can just spin up 200 servers to do the work, turn it off, and just pay for the time used.
The next phase of this migration is machine learning and AI, he states. He notes how the big cloud providers - AWS, Microsoft and Google - are putting big data tools right inside their data centres.
We can turn on a whole lot of services using these tools, says Drury. "This will fundamentally change the accounting software experience."
"We are just scratching the surface in terms of growth," says Sankar Narayan, chief financial officer, Xero.
"We are not relying on any particular geography to get to our targets," he says. He says Xero's new markets include Asia Pacific, with Xero opening an office in Singapore.
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