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126 questions, 454 terms and 400 topics in 20 areas.
11 results for “Message Formats”
Discord's Message Store Migrations
Discord moved from MongoDB to Cassandra to ScyllaDB as message volume grew from millions to trillions, each time for a specific and different reason.
Message Ordering
The guarantee about the sequence in which messages are delivered — normally per-partition or per-group only, and lost the moment consumption is parallelised.
Message Queue
A store that holds messages until a consumer processes them, decoupling producer availability and rate from consumer availability and rate.
At-Least-Once Delivery
The guarantee that a message will be delivered, possibly more than once — the practical default in every distributed messaging system.
Consumer Group
A set of consumers that cooperatively read one stream, with each partition assigned to exactly one member, so the group collectively processes every message once.
Outbox Pattern
Writing an outgoing message into a table in the same transaction as the business change, and relaying it to the broker separately, so the two cannot diverge.
Publish/Subscribe
A messaging pattern where each published message is delivered to every interested subscriber, rather than to one competing worker.
Visibility Timeout
The period after a consumer receives a message during which it is hidden from other consumers, before it becomes available again for redelivery.
Message Formats
JSON, Protobuf, Avro — schema evolution and payload economics.
Data Lakes & Lakehouses
Open formats on object storage with transactional metadata on top.
Sequence Diagrams
Ordered message exchange, and walking the failure of each arrow.