[saidajigumi]

At my last gig, we were using Firebase, Google's acquired-and-increasingly-integrated serverless solution. It was straightforward to have custom GCP instances that integrated with and extended our regular serverless workflows. In that scenario, it meant the compute instances tended to be extremely simple, as they were essentially just glorified event handlers.

Interestingly, as Firebase evolved during our use, nearly all of our external-instance use cases were obsoleted by more powerful native serverless support, esp. around functions.

All of which is the best of both worlds for serverless: an easy escape hatch to custom instances, and an ever-decreasing need for that escape hatch.