The Guides section seems to be coming along really well… A couple quick suggestions for other topics that I think might make good additions someday:
- Billing your own customers
- (When you're running an app-hosting business, consultancy, etc., on top of Fly.io.)
- This would complement the existing app-handover and "one app per customer" docs.
- Expectations for metrics in this context.
- API access to fine-grained billing (or lack thereof).
- (When you're running an app-hosting business, consultancy, etc., on top of Fly.io.)
- Dealing with an ongoing capacity crunch
- Recognizing this transient situation in the logs /
flyctlmessages. - Rescuing volumes when the attached Machine won't boot.
- Special case for Legacy Postgres.
- Downloading volume contents under the above conditions.
- Moving builders to a different region.
- Avoiding in the future (links to older docs).
- Recognizing this transient situation in the logs /
Anyway, just a couple more ideas, 
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