Microservice Architecture 101

A comprehensive guide to understanding and implementing microservice architecture, from foundational concepts to production-ready patterns.

Introduction

Through building and maintaining distributed systems, I've learned that microservices aren't just about splitting code—they're about organizational alignment, data ownership, and embracing distributed systems complexity. This series shares practical knowledge gained from real projects, focusing on patterns that work and pitfalls to avoid.

Learning Path

Articles

#	Article	Topics
1	Introduction to Microservices	Monolith vs microservices, when to use, trade-offs, Conway's Law
2	Service Decomposition Strategies	Bounded contexts, business capabilities, strangler fig pattern
3	API Design for Microservices	REST principles, versioning, contracts, OpenAPI with FastAPI
4	Synchronous Communication	HTTP/REST, gRPC, service discovery, load balancing
5	Asynchronous Communication	Message queues, event-driven patterns, RabbitMQ, Celery
6	API Gateway Pattern	Gateway responsibilities, routing, authentication, rate limiting
7	Database per Service	Data ownership, polyglot persistence, data isolation
8	Distributed Data Patterns	Saga pattern, event sourcing, CQRS, distributed transactions
9	Resilience Patterns	Circuit breaker, retry, timeout, bulkhead, fallback
10	Observability	Distributed tracing, centralized logging, metrics, health checks
11	Containerization & Deployment	Docker for microservices, Docker Compose, orchestration basics
12	Service Mesh & Governance	Service mesh concepts, security, versioning, team organization

Technology Stack

This series uses Python with modern tools:

Category	Technology
Framework	FastAPI (Python 3.11+)
Database	PostgreSQL, Redis
Messaging	RabbitMQ, Celery
Containerization	Docker, Docker Compose
Observability	OpenTelemetry, Prometheus
API Documentation	OpenAPI/Swagger

Sample Project Structure

microservices-demo/
├── services/
│   ├── user-service/
│   │   ├── src/
│   │   │   ├── api/
│   │   │   ├── domain/
│   │   │   ├── infrastructure/
│   │   │   └── main.py
│   │   ├── tests/
│   │   ├── Dockerfile
│   │   └── pyproject.toml
│   ├── order-service/
│   │   └── ...
│   └── notification-service/
│       └── ...
├── gateway/
│   └── ...
├── shared/
│   ├── schemas/
│   └── utils/
├── docker-compose.yml
├── docker-compose.prod.yml
└── README.md

Prerequisites

Before starting this series, you should be familiar with:

• Python fundamentals and async programming

• REST API concepts

• Basic SQL and database concepts

• Docker basics (helpful but not required)

• Git version control

Related Resources

This series complements other content in this knowledge base:

• Software Engineering 101 - Core engineering practices

• Database 101 - Database fundamentals

• Domain-Driven Design - DDD concepts

Key Principles

Throughout this series, we emphasize:

1. Start Simple - Don't microservice everything from day one

2. Design for Failure - Distributed systems fail; plan for it

3. Data Ownership - Each service owns its data

4. Independent Deployability - Services deploy independently

5. Observable Systems - You can't fix what you can't see

6. Team Alignment - Architecture reflects organization structure

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Let's begin with Article 1: Introduction to Microservices