It's a PaaS service like Heroku and others. However it's the new generation of "serverless" billing models where you don't worry about instances/nodes/servers a

It's a PaaS service like Heroku and others. However it's the new generation of "serverless" billing models where you don't worry about instances/nodes/servers at all and pay in much finer-grained increments. Basically node-js servers running your code with an integrated CDN, but they also support Go, Python and Ruby for running server-side logic.