For me the missing bit in Fly is scheduled tasks. I know how to solve this by spinning up an app that runs permanently as a scheduler, but basic cron-like scheduling should be part of the platform IMO. All other FaaS-like service do this.
[0] - https://docs.celeryq.dev/en/stable/userguide/periodic-tasks....
I think that Render solved "Cron as a Service" beautifully: