Microservices are small, independent services that work together to form a system.
Each one runs its own logic, stores its own data and can be built, deployed and scaled on its own.
π Why Microservices?
π‘ Independent scaling: Scale only what needs scaling. Stop wasting resources on monoliths.
π Faster deployment: Each microservice has its own CI/CD pipeline.
π§ͺ More testing flexibility: Test parts of your system in isolation.
π₯ Smaller teams: Teams work on different services in parallel.
π Tech flexibility: Use the best tool for the job, language, platform, database or framework.
πΈ Easier legacy integration: Wrap old systems inside microservices and evolve at your pace.
π¦ Real-World Example
Imagine an e-commerce platform built with microservices:
Service | Responsibility | Tech Stack |
|---|---|---|
π Cart Service | Add/remove items | Node.js + Redis |
π· Product Service | Manage product catalog | Python + PostgreSQL |
π³ Payment Service | Handle transactions | Java + Stripe API |
π¦ Shipping Service | Fulfill and track deliveries | Go + RabbitMQ |
π€ Auth Service | Manage login and permissions | .NET + Azure AD |
Each service is deployed independently and communicates via REST or messaging (like RabbitMQ or Azure Service Bus).
π Core Principles
1. Independence of Design
Each service must be isolated in logic and data. No shared databases.
2. Independent Deployment
Services should run anywhere, use containers to bundle code and dependencies.
3. Loose Coupling
Limit dependencies. Prefer asynchronous messaging. Avoid chained API calls.
4. Data Ownership
Each microservice must own its data. Changes are shared via events.
5. Idempotency
Design messages so re-processing them doesn't break the system.
π‘ Resilience Tactics
π Retry with backoff
Retry failed requests with increasing delay: 10ms β 20ms β 40ms...π§― Circuit breakers
Stop retrying when a service is clearly failing.π© Bulkheads
Limit concurrent requests per service to avoid system-wide crashes.π¬ Message deduplication
Use message IDs and reject duplicates:
if (receivedMessages.has(message.id)) {
return; // already processed
}
receivedMessages.set(message.id, true);
Microservices are more than a design choice.
Theyβre a strategic advantage that brings scalability, flexibility and speed to modern software teams.