Build services focused on specific business domains and functionality

Service-oriented architectures (SOA) define services with well-delineated functions that are driven by business needs. Microservices use domain models and bounded contexts to define service boundaries along business context lines. Focusing on business domains and functionality helps teams define independent reliability requirements for each service, improving overall resilience and scalability. Bounded contexts isolate and encapsulate business logic, enabling teams to better reason about handling failures and managing complexity.

Establish domain-focused service champions in each team: Assign domain-focused service champions within each workload team to oversee the design of services around specific business domains and functionality. These champions ensure that services are built with a clear focus on business requirements, encapsulating related logic within bounded contexts for better maintainability and reliability.

Provide training on domain-driven design and bounded contexts: Train builder teams on best practices for domain-driven design (DDD) and defining bounded contexts. Training should include understanding business domains, drawing appropriate boundaries, and applying SOA and microservices principles. Proper training helps teams develop services that are aligned with business needs and isolate complexities within specific contexts.

Develop domain-focused service guidelines and standards: Create clear guidelines for designing services based on business domains and functionality. These guidelines should cover identifying business boundaries, creating bounded contexts, and defining service responsibilities. Documented standards help ensure consistency and alignment across teams, making it easier to develop services that meet business requirements and reliability standards.

Integrate domain-driven validation into CI/CD pipelines: Integrate validation checks into CI/CD pipelines to ensure that new services are designed around well-defined business domains and bounded contexts. Automated checks can verify that services are independent, encapsulate appropriate business logic, and do not overlap in responsibilities. This ensures that service boundaries are respected throughout the development lifecycle.

Define automated guardrails for domain-focused service boundaries: Use automated tools to enforce domain-driven service boundaries, ensuring that services are designed with a clear focus on business domains. Tools like AWS Step Functions, AWS Lambda, and Amazon EventBridge can help enforce the separation of concerns and guide teams in maintaining service boundaries. Automated guardrails help prevent unnecessary coupling and keep services well-aligned with their intended business context.

Foster a culture of business-driven service design: Encourage builder teams to prioritize business needs when designing services. Recognize and reward teams that effectively segment their workloads based on business functionality and create bounded contexts that encapsulate complexity. Open discussions about the benefits and challenges of domain-driven design can help create a culture of continuous improvement focused on developing resilient, business-aligned services.

Conduct regular service boundary reviews: Schedule regular reviews to assess service boundaries and ensure that they align with business domains and requirements. These reviews should evaluate whether the services effectively encapsulate business logic and isolate complexity, ensuring that reliability requirements are met independently for each service. Regular reviews help maintain a focus on building services that are scalable, reliable, and well-defined.

Leverage automation for consistent domain-focused service design: Use Infrastructure as Code (IaC) tools like AWS CloudFormation or AWS CDK to automate the deployment of domain-focused services. Automating these processes ensures consistency across environments and helps prevent deviations from best practices in service segmentation.

Provide dashboards for visibility into service boundaries and domains: Use dashboards to provide visibility into service boundaries, business contexts, and the reliability of individual services. Tools like Amazon CloudWatch and AWS X-Ray can help monitor the health and interactions of services within their domains. Dashboards help builder teams proactively manage service boundaries and ensure that each service is well-aligned with its business context.

Supporting Questions

• How do you ensure that builder teams define service boundaries based on business domains and functionality?
• What mechanisms are in place to validate that services are designed independently, encapsulating appropriate business logic?
• How do you align service design practices with organizational standards for scalability, reliability, and business needs?

Roles and Responsibilities

Domain-Focused Service Champion (within Builder Team)

Responsibilities:

• Guide the design of services around business domains and bounded contexts.
• Ensure that services encapsulate specific business logic and align with domain-driven design principles.

Application Developer

Responsibilities:

• Implement application features within services that align with specific business domains.
• Use automated tools to validate that service boundaries are respected during development.

Operations Team Member

Responsibilities:

• Assist builder teams with managing service dependencies and maintaining well-defined boundaries.
• Provide guidance and training to ensure alignment with best practices for domain-driven service design.

Artifacts

Domain-Focused Service Design Guidelines and Standards: A document outlining best practices for defining service boundaries along business context lines, including guidance on domain-driven design and bounded contexts.

Training Resources for Domain-Driven Design: Hands-on labs, workshops, and documentation to help teams understand how to design services focused on business domains and functionality.

Automated Service Segmentation Configurations: Scripts and configurations that help automate the deployment of services within specific business contexts, ensuring consistency across environments.

Relevant AWS Services

Training and Awareness Tools:

• AWS Skill Builder and AWS Well-Architected Labs: Resources for learning about domain-driven design, service-oriented architecture, and microservices best practices.
• AWS Trusted Advisor: Provides insights into application architecture and recommendations for improving the alignment of services with business domains.

Domain-Focused Service Design and Guardrails:

• AWS Lambda: Helps develop services that align with specific business functionality, supporting a microservices architecture.
• AWS Step Functions: Orchestrates workflows across services within specific business domains, promoting separation of concerns.
• Amazon EventBridge: Helps manage event-driven communication between services, maintaining well-defined boundaries and reducing coupling.

Monitoring and Visibility Tools:

• Amazon CloudWatch: Tracks the health and performance of domain-focused services, providing alerts for reliability issues.
• AWS X-Ray: Helps trace requests across services, identifying dependencies and verifying that services are well-aligned with their business domains.
• AWS CloudFormation: Codifies service configurations, automating the deployment of domain-focused services and ensuring consistency across environments.