A. Design pattern

Separation of Concerns

• Keep frontend, backend, and database independent.

Service-Oriented Architecture (SOA)

• Microservices communicating over: microservice in details
• REST
• gRPC
• messaging systems :
  • rmq
  • kakfa

API-first Development:

• Design APIs before implementation to enable parallel development.

Event-Driven Architecture

• Use event streams for real-time updates
• Kafka,
• AWS::SQS + AWS::EventBridge
• RMQ::StreamingQueue

Serverless Architecture (auto-scale,etc)

• AWS :: Lambda
• for scalable and cost-effective solutions.
• Other AWS serverless offering
• fargate (ECS/EKS)
• sqs,s3
• AWS DB :: DynamoDB,Aurora

Twelve-Factor App

• Guidelines for building scalable and maintainable applications.
• -02_twelve_factor_app.md

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B. Infrastructure components:

Front-end

• framework:
• Reactjs : project-1 | project-2(redux)
• Angular 2+ :
  • js/html/css : front-end-pack
  • ng: Angular project-1 MEAN-stack | Angular project-2 OTT
  • css more: css notes-1 | css notes-2
• Vue.js
• SPA
• PWA

Backend

• GraphQL APIs : pending
• frameworks for RESTful APIs
• java --> SpringBoot
  • 00_Springboot
• js/ts/nodejs --> Express.js
  • project-1

• py --> Django/fastApi

  • project-2

• API Gateway:

• Routing, authentication, rate-limiting
• ingress server in K8s
• Microservices
• deploy via
  • containers (Docker)
  • orchestration (Kubernetes) : pods+services
  • 03_Kubernetes
• https://github.com/lekhrajdinkar/03-spring-cloud-v2/tree/main/Notes
• 01_monolith_MicroServices.md00_kickOff
• Load Balancers
• AWS :: ELB/Elastic Load Balancer - alb, nlb,
• NGINX
• Cloud services : AWS: lambda, s3, sqs, etc
• 01_aws

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Database

• Relational Databases:
• PostgresSQL / Aurora(serverless)
• MySQL
• NoSQL Databases
• MongoDB,
• Cassandra,
• AWS:DynamoDB
• Horizontal scaling : aws serverless takes care
• Distributed architecture
• primary writer instance
• multiple READ instance
• replication with encryption at rest.
• AWS serverless takes care.
• Caching:
• Redis
• Memcached

CI/CD pipeline

• GitHub Actions
• Harness
• containerization: docker/k8s

Observability and Monitoring (log,metric,traces)

• OpenTelemetry
• micrometer
• Prometheus, grafana, AWS:CloudWatch
• Application health
• distributed tracing
• AWS:CloudWatch>x-rays

Authentication and Authorization

• 01_web_Security
• SAML + SSO
• LDAP
• Okta
• OAuth 2.0,
• OpenID Connect

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C Design Aspect

scalability

reliability

flexibility

maintainability

Observability