Istio’s 2017 announcement invited you to imagine that you could “transparently inject a layer of infrastructure between a service and the network that gives operators the controls they need while freeing developers from having to bake solutions to distributed system problems into their code”. It is worth noting that it does not specifically mention the method by which this vision would be realised. Sidecars were always an implementation detail to us on the Istio team; one that provided the ability to do something which was otherwise so complicated as to be impractical for most users, but not…