Basecamp (formerly 37 Signals) is quitting the cloud. One of the founders gives some reasons, and he had some detail in a tweet on what they've spent in the cloud the last few years. Over USD$3mm on various services, though their costs in search seem very high. I don't, and haven't, run as busy a business as they do, so I don't know if they've truly done a good job architecting things and setting up services. They say they have, though I'd expect everyone to say and think that.
However, I'll assume they are correct and they can't optimize things any more than they are currently. Their decision makes some sense, and I agree with it. I've been surprised at the growth of the cloud, both in size and how quickly people are moving to the cloud. I've also been saying for years that if you have a steady or known workload, the cloud is likely very expensive.
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