Matteo Rossi

Table of Contents IntroductionWhy “Clean Core” Still Matters in 2026Hexagonal Architecture Recap Ports: Defining What the Core NeedsThe Domain Model Must Stay IgnorantMongoDB as an Adapter — Not a RepositoryMapping Between Domain and Persistence ModelsTesting: Where the Architecture Pays OffSpring Boot …

Table of Contents Reactive Streams: The Contract Behind ReactorProject Reactor Core ConceptsBackpressure: The Hard Part Reactive Does Not Mean FasterMongoDB Reactive Driver: Architecture OverviewIntegrating MongoDB Reactive Driver with Project ReactorPerformance Considerations with Reactive MongoDBReactive Architecture Patterns with MongoDBWhen NOT to Use …

Table of Contents GraphQL fundamentals Why GraphQL fits well in the Spring ecosystemChoosing Netflix DGS with Spring for GraphQLProject setupDependenciesDomain model overviewDefining the GraphQL schemaPersistence with MongoDBQuery resolvers with Netflix DGSMutations and input validationResolving relationships in MongoDBThe N+1 query problemUsing DataLoader …