AWS infrastructure and security foundation

Infrastructure and security. SpendWiseApp on AWS Cloud follows a three-tier pattern suited to web workloads and cost-conscious scaling:

• Presentation tier — user experience and frontend hosting (for example Amplify).
• Application tier — APIs and business logic (for example ALB, ECS Fargate, ECR).
• Data tier — durable storage and databases (for example RDS PostgreSQL, Secrets Manager for DB credentials).

Implementation detail is split by technical layer (VPC → Frontend Hosting and user authentication → backend runtime → database), aligned with those modules:

1. 4.2.1 VPC and networking.
2. 4.2.2 Frontend Hosting and user authentication
3. 4.2.3 Backend and runtime platform
4. 4.2.4 Database.