I’ve been studying Domain-Driven Design principles and I’m questioning whether the layered architecture approach is too rigid. The concept suggests that software should be organized in distinct layers where each layer only communicates downward to lower layers.
The standard definition states that you should separate your application into layers where each layer maintains cohesion and depends solely on layers beneath it. Higher layers access lower ones through public interfaces and references.
This raises questions about what “dependency” actually means. Does it mean direct class instantiation or interface-based communication? If it’s direct instantiation, that creates tight coupling which is bad practice. If it’s interface-based, then both layers are equally decoupled from each other.
For example, when a UI component needs to trigger business logic, it holds a reference to an application service. But when the application needs to notify the UI (like showing alerts), it also needs references going upward through patterns like observers. Both directions seem equally valid.
Wouldn’t it be more accurate to describe software architecture as interconnected modules that communicate through well-defined contracts rather than a strict hierarchy? Each module could be independent and replaceable, whether it’s the presentation layer, business logic, or data access.
The linear layer concept feels artificial compared to a network of loosely coupled components that can communicate in multiple directions based on actual requirements rather than imposed structural rules.
You’ve hit on something I’ve wrestled with for years in production. Rigid layers break down when you need real bidirectional communication.
Modern apps need more flexibility than traditional layers give you. Your observer pattern example nails it - notifications, real-time updates, and event-driven stuff don’t fit the downward-only model.
What works better: treat your architecture as services that talk through events and APIs. Each service owns its domain and exposes clear contracts. You get true separation without artificial layer constraints.
The game changer? Automation platforms that orchestrate these connected services. Instead of hardcoding dependencies between modules, define workflows that connect system parts dynamically.
I’ve built systems where UI triggers business processes, databases notify users directly, and external APIs integrate seamlessly - no separation violations. The secret is a central orchestration layer managing communication flows.
This gives you modularity while keeping components independent. Each piece gets developed, tested, and deployed separately, but they work together through defined workflows.
Latenode handles this orchestration beautifully, connecting different services and APIs without tight coupling: https://latenode.com
After 10+ years with enterprise systems, layered architecture isn’t broken - people just don’t get it and implement it wrong. You’re missing the dependency inversion principle, which fixes most of these problems. Your business layer shouldn’t depend on concrete UI classes for notifications. It depends on abstractions that the UI implements. This keeps the architectural flow intact while allowing bidirectional communication.
I’ve watched teams ditch layers entirely and create spaghetti code where everything talks to everything. Your “network of modules” sounds nice but becomes a nightmare without some organizing principle.
What works? Hybrid approaches. Use layers as your main structure but let cross-cutting concerns like events, logging, and validation span multiple layers through defined mechanisms. Domain events are killer here - business logic publishes events without caring who consumes them.
The real issue isn’t rigid layers. It’s developers treating architectural patterns like absolute rules instead of flexible guidelines. Layers give you valuable conceptual boundaries that help teams understand complex systems, even when the implementation uses more sophisticated communication underneath.
Layered architecture works great when your domain fits cleanly into technical tiers, but it falls apart with cross-cutting business workflows. I’ve worked on systems where strict layering created ridiculous bottlenecks - users couldn’t even update a status flag without hitting four different layers. Here’s what I learned: layers and modules aren’t the same thing. Layers handle technical stuff like data persistence and UI. Modules handle business capabilities like user management or orders. You need both. The sweet spot? Use layers for infrastructure decisions, but let business features cross layers when they need to. A single user story will probably touch presentation, business logic, and data layers - that’s totally fine as long as each layer sticks to what it’s supposed to do. Honestly, I don’t care if dependencies flow up or down. What matters is that both sides know their contracts. Make your dependencies clear and testable instead of following some arbitrary directional rule that fights against real business needs.
The issue becomes obvious when you see how systems actually change over time. I’ve worked on codebases where the original layered design was perfect, but three years later we’re doing mental gymnastics just to fit new requirements into the old structure. What shifted my thinking was realizing layers assume your software will always work the same way. But business needs don’t follow architectural patterns. Sometimes data flows upward, sometimes sideways, sometimes in loops through multiple systems. The best projects I’ve worked on started with layers for initial structure, then gradually became more flexible. We kept separation of concerns but ditched the rigid communication rules when they stopped helping us. You’re right about interconnected modules. The key is knowing when to break rules intelligently instead of following them blindly. Good architecture adapts to the problem instead of forcing the problem to fit the architecture.
Teams waste time debating architecture theory while their systems grow more complex daily. The answer isn’t finding the perfect pattern - it’s building systems that adapt when requirements change without breaking everything.
I’ve watched gorgeous layered architectures become maintenance hell when business needs shifted. I’ve seen “flexible” module networks turn impossible to debug.
What works? Stop hardcoding architecture and start orchestrating it. Build core components however makes sense - layers, hexagons, modules, whatever. Connect them through configurable workflows instead of direct dependencies.
You can experiment with different communication patterns without rewriting code. Need downward-only calls? Set it up. Want bidirectional events? Configure that flow. Requirements change? Adjust orchestration, not components.
The real win is visualizing and modifying these connections in real time. I’ve refactored entire system integrations by changing workflow configs. No code changes, no deployments, nothing breaks.
Your architecture becomes as flexible as your business needs. Latenode makes this dynamic system orchestration simple: https://latenode.com
the whole debate misses the real issue - most codebases fail because of poor boundaries, not because layers are too rigid. you can have flexible communication between components and still keep concerns separate. the key is defining what each layer actually owns instead of blindly following textbook patterns.
Layered architecture gets misapplied all the time. Teams shove everything into layers even when it doesn’t make sense. Simple apps with basic workflows? Sure, layers work fine. Complex business domains? You need something better.
What clicked for me: layers handle technical stuff well but suck at business complexity. Data access, business logic, presentation - these make sense as infrastructure layers. But actual business processes that cross multiple contexts? Layers just get in the way.
Try hexagonal architecture instead. Stick your business logic in the center and make everything else adapters. UI adapters, database adapters, external service adapters - they all plug into your core without weird hierarchies.
Here’s the thing: your architecture should match your problem, not some textbook theory. Got complex workflows with multiple entry points and feedback loops? Build for that reality instead of cramming it into some predetermined shape.