In my experience with much smaller teams (5-50 programmers) the main challenges are three-fold: 1) getting developers to talk about formalizing (to any degree)

In my experience with much smaller teams (5-50 programmers) the main challenges are three-fold: 1) getting developers to talk about formalizing (to any degree) cross-system responsibility at all rather than just hanging code where it's easiest at-hand; 2) getting developers to think about external inputs/outputs at all and everything that entails, e.g. namespacing, versioning, forwards and backwards compatibility, validation, access control, ... 3) teaching developers to pick the right kind of interface for their data and processing, i.e. more or less queue vs. pubsub vs. RPC vs. REST vs. query language; of the three this is the only "technical" one, the others will be harder sells. Once you have done these, the question of _which_ queue/etc. you take is largely irrelevant; there will be some natural pressure to standardize and even "unnatural" pressure from CTOs/management will be straightforward to implement.