Pretty well... neat!
Let's talk about scaling. This is, roughly, incremental re-architecture to meet current and projected load. It usually means increased complexity over time, whether it's just "stick a cache in front of this" or "we now need work queues & workers & many μservices.
The code might be open-source, but the operations cannot be. (npm, home of OS maniacs, in practice doesn't OS its services because they would be meaningless sans AWS, a CDN, & a lot of glue.)
Risks and challenges: not negativity, but asking what happens next.
Federation: I understand why people burned by centralized networks love it. In practice it is not a concept non-nerds either understand or want. It's an implementation detail.
Non-universal names are a bug not a feature to most people.
Centralization has usability benefits.
So expect convergence on this shard & confusion when it falls over.
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