Matteo Rossi

Table of Contents The Problem with Stateless ChatWhat We Are BuildingTwo Different Kinds of MemoryMix & MatchShort-Term Memory: Keeping the Conversation CoherentLong-Term Memory: Carrying Knowledge Across SessionsMemory Consolidation: From Conversation to Durable FactThe Advisor Chain and Why Order MattersThe Atlas …

Table of Contents The problemWhat we are buildingWhy RAG and why MongoDB AtlasHow the Pieces Fit TogetherGetting the Project RunningThe Ingestion PipelineThe Retrieval PipelineThe Atlas Vector Search IndexTrying It OutConclusion and What’s NextThis is the first article in a three-part …

Table of Contents Rethinking ETL for modern systemsArchitectural building blocksEmbracing concurrency with reactive pipelinesBackpressure: the hidden heroDesigning for failure: error handling strategiesRetry and recovery patternsIdempotency: the cornerstone of safe retriesBatching vs streamingParallelizing transformationsIntegrating with messaging systemsObservability and monitoringPutting it all …

Table of Contents Why Cache Invalidation Becomes Hard in Distributed SystemsTime-Based Expiration (TTL)The Cache-Aside PatternEvent-Based Cache InvalidationVersioned Cache KeysMulti-Layer CachingEvent-Driven Cache RebuildsChoosing the Right StrategyFinal ThoughtsCaching is one of the most powerful tools developers have at their disposal for optimizing …

Table of Contents Creating Non-Blocking Streaming Endpoints for High-Throughput ApplicationsFrom Snapshots to StreamsProject SetupDomain Model: Telemetry as a Streamable DocumentReactive RepositoryService Layer: Explicit Backpressure StrategyStreaming Endpoint with Server-Sent EventsThe Real Bottleneck: Waiting, Not WorkingThe Most Dangerous Line of CodeResource Efficiency …

Table of Contents Authorization Is a Business ConcernModeling Permissions FirstUsing MongoDB for User MetadataFrom Infrastructure Model to Application PrincipalCentralizing Authorization LogicContextual Rules: Where RBAC StopsRBAC vs ABAC: When Roles Are Not EnoughThe Architectural PayoffConclusionWe often work with Java applications where …

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 …