Contemporary systems are increasingly complex, with both large codebases and constantly changing environments which make them challenging to develop, deploy and manage. We consider two recent efforts to tackle this complexity: microservices and emergent software. Microservices have gained recent popularity in industry, in which monoliths of software are broken down into compositions of single-objective, end-to-end services running on HTTP which can be scaled out on cloud hosting systems. From the research community, the emergent systems concept demonstrates promise in using real-time learning to autonomously compose and optimise software systems from small building blocks, rapidly finding the best behavioural composition to match the current deployment conditions. We argue that emergent software and microservice architectures have strong potential for synergy in complex systems, offering mutually compatible lessons in dealing with complexity via scale-out design and real-time client-tailored behaviour. We explore self-designing microservices, built with emergent software, to demonstrate the complementary boundaries of both concepts - and how future intersections may offer novel architectures that lie at a compelling point between human- and machine-designed systems. We present the conceptual synergy and demonstrate a specific microservice architecture for a smart city example where scoped microservices are continually self-composed according to the demands of the applications and operating environment. For the purpose of reproducibility of the study, we make available all the code used in the evaluation of the proposed approach.