Software Architecture and Software Design

#software #architecture #design #patterns

Based on both key definitions, software architecture and software design, we can lay down an organization of software principles, methodologies and patterns currently applied in modern software development and technology innovations.

Software Architecture

It's a high level blueprint for a system.
It defines the structural elements like subsystems, roles, relationships and responsibilities meaning it lays down the architecture style, patterns that will guide the software design.
Software architecture directly deals with arranging this elements like servers, databases, APIs, clients or users of the software application, etc in order to fulfill business requirements.

Software Design

Implies decisions at a lower level of detail as it provides an implementation plans for the laid out architecture.
Software designers will decide on the specifications, contracts used in these subsystems that later software engineers will implement.

Organization of software principles, methodologies and patterns

Index of software concepts:

Software architecture style
Software architecture patterns
Software design methodologies
Software design patterns
Programming paradigms
Clean code principles

1. Software Architecture Style

Based on Structure (separation of concerns)

Layered architecture (N-tier):Common for separation of concerns (e.g. presentation, business logic, data layers).
Hexagonal architecture (Ports & Adapters): Focused in decoupling core logic from external systems.

Based on distribution of the application

Monolith architecture
Microservices architecture
- Microservices patterns

Events

Focuses on asynchronous communication through events.

Event Driven architecture

Cloud

Involves event triggered functions (AWS Lambda) rather than traditional server management.

Serverless architecture

API Design

REST over HTTP

2. Software Architecture Patterns

Based on data management

Database per service (microservices)
Shared database (monoliths)

Event driven systems

CQRS: Common Query Responsibility Segregation, Separating read and write operations.
Domain event
Event sourcing: Store state changes as sequence of events.

Based on transactional messaging

Ensures reliable message delivery in distributed systems.

Transactional outbox

Based on security

Access tokens (Authentication)
Oauth (Authorization)
Session

Based on observability

Essential for monitoring and troubleshooting in distributed systems.

Log aggregation
Application metrics
Exception tracking
Health check API

3. Software Design Methodologies

Domain Driven Design (DDD): Focuses on modeling the domain and aligning software design with business needs.
Behavior Driven Development (BDD): emphasizes collaboration between developers, testers and business stakeholders.
Test Driven Development (TDD): involves writing tests for core domain logic before coding to ensure quality and maintainability.

4. Software Design Patterns

Creational Patterns
Structural Patterns
Behavioral Patterns

Expand on software design patterns

5. Programming Paradigms

Object Oriented Programming (OOP)
- Composition over inheritance
- SOLID
  - Single-responsiblity Principle
  - Open-closed Principle
  - Liskov Substitution Principle
  - Interface Segregation Principle
  - Dependency Inversion Principle
Functional Programming: emphasizes immutability and pure functions.

6. Basic principles

Clean Code
DRY: Don't repeat yourself
KISS: Keep it stupid simple
YAGNI: You aren't going to need it

Take into account that all these architectural principles, methodologies and patterns are no substitute for making your own decisions. You need to balance them according to business requirements of your software application.