Beyond the general constraints on architectural decisions .(listed above), I've imposed the following constraints to limit the option space:

No changes to the client interface of the circulation APIs
- excludes using hypermedia controls to defer fetching some data
Only existing infrastructure can be used (I'm including Kafka in this, even though it isn't official yet)
- excludes options which including changing the storage technology e.g. MongoDB or integration mechanism e.g. gRPC

Analysis

Limitations of Analysis

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