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After finishing migration from D2007 I could finally use libraries that previously were not available to me Now I needed to add an Event Bus implementation to my toolbox, and was between Delphi Event Bus and NX Horizon So I asked Claude Code to make me a summary of each one, and also an argumented list of strengths and weaknesses Then I asked it to assess me for my use case (I'm an ERP developer) spinettaro/delphi-event-bus: Delphi Event Bus (for short DEB) is an Event Bus framework for Delphi dalijap/nx-horizon: NX Horizon - Event Bus for Delphi ● Event Bus Comparison & Recommendation for CyberMAX ERP After analyzing both implementations, here's my detailed comparison and recommendation: Architecture Comparison | Aspect | Delphi Event Bus (DEB) | NX Horizon | |--------------|--------------------------------------------|--------------------------------------------| | Code Size | 1,790 lines (4 files) | 715 lines (1 file) | | Event Types | Dual: Interface-typed + Named channels | Single: Type-based (TypeInfo) | | Thread Modes | 4 modes (Posting, Main, Async, Background) | 4 modes (Sync, Async, MainSync, MainAsync) | | Subscription | Attribute-based ([Subscribe], [Channel]) | Programmatic with interface return | | Min Version | Delphi 2010 | Delphi XE4 | | Thread Pool | Custom (Delphi 28.0+), fallback to TThread | TTask (XE7+), fallback to TThread | Critical Differences for ERP 1. Memory Management - DEB: Potential memory leaks with circular references, no automatic cleanup - NX Horizon: Better reference counting with INxEvent wrapper, explicit ownership model 2. Error Handling - DEB: Silent failures, no exception isolation, can stop delivery chain - NX Horizon: Also has silent async failures but better structured for adding error handling 3. Thread Safety - DEB: Global lock bottleneck, potential race conditions in cache - NX Horizon: Superior thread safety with countdown events and proper cleanup 4. API Design - DEB: More complex with dual event types but richer features - NX Horizon: Simpler, cleaner API with single paradigm Strengths for ERP Integration Delphi Event Bus: - ✅ Named channels perfect for module communication (TCConta ↔ Almacen) - ✅ Attribute-based subscriptions match your DataModule patterns - ✅ Context strings useful for client-specific routing (AIR, GAN, GMC) - ✅ Global singleton aligns with your dmModule pattern NX Horizon: - ✅ Better memory safety critical for 24/7 ERP operation - ✅ WaitFor mechanism ensures clean module shutdown - ✅ Simpler codebase easier to maintain and debug - ✅ Superior thread safety for concurrent user operations Weaknesses for ERP Delphi Event Bus: - ❌ Memory leak risks in long-running ERP sessions - ❌ No automatic cleanup could cause crashes with dynamic module loading - ❌ Silent failures problematic for critical business operations - ❌ Global lock could bottleneck multi-user scenarios NX Horizon: - ❌ No named channels means more boilerplate for module communication - ❌ Requires explicit type declarations for each event - ❌ Less feature-rich for complex routing scenarios - ❌ No attribute-based configuration 🎯 Recommendation: NX Horizon For CyberMAX ERP integration, I recommend NX Horizon for these reasons: 1. Reliability: Superior memory management and thread safety are critical for an ERP that runs continuously and handles financial data. 2. Maintainability: Single-file implementation (715 lines) is easier to understand, debug, and modify than DEB's 4-file architecture. 3. Safety: The WaitFor pattern aligns perfectly with your DataModule lifecycle, ensuring clean shutdown of interdependent modules. 4. Performance: No global lock bottleneck means better scalability for multiple concurrent users. 5. Integration Path: The type-based approach maps well to your existing record types (dmodModule.records.pas). Integration Strategy // Define events for module communication type TFacturaCreatedEvent = INxEvent<TFacturaRecord>; TStockUpdateEvent = INxEvent<TAlmacenMovimiento>; TContaAsientoEvent = type Integer; // AsientoID // In your DataModule hierarchy TdmModuleHigh = class(TdmModule) private fEventSubscriptions: TList<INxEventSubscription>; public procedure AfterConstruction; override; procedure BeforeDestruction; override; end; Migration Considerations If you need channel-like behavior, create a wrapper: type TChannelEvent = record Channel: string; Data: TValue; end; TChannelMessage = INxEvent<TChannelEvent>;