I&#x27;m a lone dev too.  I&#x27;ve been using microservices with Google App Engine.  By using some templates and some conventions I find it easy to create modular back-ends.<p>Basically I design using fairly detailed use cases and data model.  Then each scenario in the use cases is implemented as a microservice.  This approach makes single responsibility design rather easy.  As business requirements evolve, the updated use cases lead to changes and additions.  All rather neat and easy.