[jkarneges]

My understanding is a Durable Object is similar to a long running JS app in a respawnable/relocatable container (imagine a Kubernetes deployment of 1 pod). There is always exactly one instance, somewhere. And because the instance is long running, WebSockets become more practical.

Note that because Durable Objects are long running computations, they are stateful and deployments are disruptive (clients disconnected). So even though you could potentially put them in the "serverless" category, the deployment experience isn't quite the same as short-lived serverless functions / lambdas.

The real novelty of Durable Objects appears to be their intended usage of fine granularity (and the underlying tech that enables this). For example, if you were building a chat room service, you could have 1 Durable Object per room. Of course, you could conceivably build a chat room service running 1 Node.js process per chat room on traditional VMs or containers, but that probably wouldn't scale well.

[kentonv]

Thanks, you explained it much better than I could.

[frakkingcylons]

I was struggling to wrap my head around Durable Objects, this was very useful.