What are microservices?

Microservices are an architectural style where an application is built as a collection of small, autonomous services, each performing a specific business function.

Main characteristics:

• Small and focused: Each service addresses a narrow task.
• Autonomous: Can be developed, deployed, and scaled independently.
• Decentralized data management: Each service can have its own database.
• Inter-service communication: Usually occurs through lightweight protocols (e.g., REST, gRPC).
• Fault tolerance: Failure of one service does not necessarily lead to the failure of the entire application.
• Technological heterogeneity: Different services can use different programming languages and technologies.

Advantages:

• Accelerated development and deployment.
• Better scalability of individual components.
• Increased resilience.
• Easier adoption of new technologies.

Disadvantages:

• Increased system complexity overall.
• Need to manage distributed transactions.
• Challenges with monitoring and debugging.
• Requires a more mature DevOps culture.

Comparison with monolith:

Characteristic	Microservices	Monolith
Size	Small, focused services	One large application
Deployment	Independent deployment of services	Deployment of the entire application
Scalability	Scaling of individual services	Scaling of the entire application
Fault tolerance	High (failure of one service is not critical)	Low (component failure affects all)
Technologies	Ability to use different stacks	Single technology stack
Development team	Small autonomous teams	One large team
Complexity	High (service interaction)	Low (for simple applications)
Data management	Decentralized	Centralized