Not sure why you refer to our team as "we" but you can use even 2.x Java and .NET
clients with RabbitMQ 3.x if you don't care for certain protocol extensions. Core
protocol hasn't changed in a while and official clients don't require upgrading in lock step.
If you use something like Spring AMQP, however, the exact client version may matter more,
and YMMV .
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MK
Staff Software Engineer, Pivotal/RabbitMQ