Hi, Dylan, a co-founder here. It's a great question.
We've found that for integrations or common automations, building on a cloud platform is too low-level. You've got to manage a number of services that aren't core to your use case (e.g. API Gateway, IAM, Cloudwatch Logs, etc.). We operate at a higher level and just give you an execution environment to run Node.js code or stitch together pre-built actions, similar to integration platforms like Zapier.
Of course, Serverless and other frameworks abstract part of the cloud services, but you're still running on that platform, and when you need to troubleshoot or scale the service, it's likely you'll have to peek under the covers. We tried to build a serverless platform from the ground up and provide services like the HTTP server, key-value store, logs, and other services right inside the UI, or accessible in code. There's no other cloud resources to manage or monitor.
This kind of abstraction isn't great for every application, but we think it shines when you're building integrations or data pipelines that aren't part of your core app.
The pre-built actions and built-in OAuth / key-based auth also operate at a higher level than most cloud services. We've tried to provide these in a developer-friendly way, so you have full control over how your workflow runs, but don't have to manage the parts that are tangential to the logic of your app.
As we expose more APIs for building and running workflows, we'd love to support a framework like Serverless.
I'd love if you have time to give Pipedream a try and see how it works for yourself! We're looking for feedback on how we can improve so we'd love more eyes on it.