Common Architectural Styles and When to Use Them

1. Monolithic Architecture

Concept:
All components are packaged and deployed as a single unit.

When it works best:

• Small to medium-scale applications
• Startups and early-stage products
• Teams with limited DevOps complexity

Pros: Simple deployment, easy debugging, straightforward development
Cons: Hard to scale components independently, tightly coupled codebase

2. Microservices Architecture

Concept:
System is split into loosely coupled services, each owning a single business capability.

When it works best:

• Large, complex systems
• Organizations needing independent scaling and deployments
• Teams with strong DevOps and CI/CD pipelines

Pros: High scalability, independent deployment, flexible tech stack
Cons: Operational complexity, requires strong observability and communication

3. Event-Driven Architecture

Concept:
Components communicate via events rather than direct calls.

When it works best:

• Real-time data processing
• IoT systems
• Distributed applications needing loose coupling

Pros: Highly scalable, resilient, decoupled services
Cons: Harder debugging, requires strong event management and monitoring

4. Layered (N-Tier) Architecture

Concept:
Application organized into layers (UI, business, data, etc.), each handling specific responsibilities.

When it works best:

• Traditional enterprise systems
• Academics / simple internal tools
• Systems with clear separation of concerns

Pros: Structured and easy to understand, good maintainability
Cons: Can introduce performance overhead, may feel rigid

5. Serverless Architecture

Concept:
Compute resources are managed by the cloud provider; code runs in stateless functions.

When it works best:

• Apps with variable or unpredictable traffic
• Event-driven workloads
• MVPs and low-maintenance projects

Pros: No server management, auto-scaling, cost-efficient
Cons: Cold starts, vendor lock-in, limited execution time

6. Micro-Frontends

Concept:
Front-end application broken into independent, deployable UI modules.

When it works best:

• Large UI applications
• Multi-team development
• Complex web apps with shared components

Pros: Independent deployment, tech-agnostic front-end modules
Cons: Increased complexity in routing, consistency, and shared state

Conclusion

There is no “one-size-fits-all” architecture. The right choice depends on:

• Business scale and future growth
• Team skills and size
• Operational maturity
• Performance and availability requirements
• Development speed vs. system complexity

Great architects don’t just choose a style—they align architecture with business needs and evolve it over time.

If you'd like, I can also provide:

📌 diagrams for each architecture
📊 comparison table
🧠 real-world product examples for each style
🎓 interview-style explanation