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# Project Architecture

<!-- SECTION:architecture:overview:START -->
## Architecture Overview

<!-- DATA:architecture-pattern:START -->
```yaml
pattern:
  selected: "[Choose: MVC, DDD, Microservices, Monolithic, etc.]"
  description: "Brief description of why this pattern was chosen"
```
<!-- DATA:architecture-pattern:END -->

<!-- SECTION:architecture:ddd-example:START -->
### Domain-Driven Design Example

<!-- DATA:ddd-layers:START -->
```yaml
layers:
  - name: "Domain Layer"
    path: "/domain"
    description: "Pure business logic, no external dependencies"
    components:
      - type: "Entities"
        description: "Stateful business objects"
      - type: "Value Objects"
        description: "Immutable domain concepts"
      - type: "Domain Services"
        description: "Business logic spanning multiple entities"
      - type: "Ports"
        description: "Interfaces for external dependencies"
  
  - name: "Application Layer"
    path: "/application"
    description: "Use case orchestration"
    components:
      - type: "Application Services"
        description: "Coordinate domain objects and infrastructure"
      - type: "DTOs"
        description: "Data transfer objects for API responses"
  
  - name: "Infrastructure Layer"
    path: "/infrastructure"
    description: "External integrations"
    components:
      - type: "Repositories"
        description: "Database access implementations"
      - type: "External Services"
        description: "Third-party APIs, payment processing, etc."
      - type: "Adapters"
        description: "Integration with external systems"
```
<!-- DATA:ddd-layers:END -->
<!-- SECTION:architecture:ddd-example:END -->

<!-- SECTION:architecture:alternative-patterns:START -->
### Alternative Architecture Patterns

<!-- DATA:architecture-alternatives:START -->
```yaml
alternatives:
  - pattern: "MVC"
    components:
      - name: "Models"
        role: "Data and business logic"
      - name: "Views"
        role: "User interface components"
      - name: "Controllers"
        role: "Handle requests and coordinate between models and views"
  
  - pattern: "Microservices"
    components:
      - name: "Service Boundaries"
        role: "Each service owns its data and logic"
      - name: "Communication"
        role: "REST APIs, message queues, or gRPC"
      - name: "Service Discovery"
        role: "How services find each other"
  
  - pattern: "Clean Architecture"
    components:
      - name: "Entities"
        role: "Business objects"
      - name: "Use Cases"
        role: "Application business rules"
      - name: "Interface Adapters"
        role: "Controllers, presenters, gateways"
      - name: "Frameworks & Drivers"
        role: "External tools and frameworks"
```
<!-- DATA:architecture-alternatives:END -->
<!-- SECTION:architecture:alternative-patterns:END -->
<!-- SECTION:architecture:overview:END -->

<!-- SECTION:architecture:core-concepts:START -->
## Core Concepts

<!-- DATA:key-components:START -->
```yaml
components:
  - name: "[Component Name]"
    responsibility: "[Description of the component's responsibility]"
    dependencies: []
  - name: "[Component Name]"
    responsibility: "[Description of the component's responsibility]"
    dependencies: []
  - name: "[Component Name]"
    responsibility: "[Description of the component's responsibility]"
    dependencies: []
```
<!-- DATA:key-components:END -->

<!-- DATA:domain-concepts:START -->
```yaml
concepts:
  - name: "[Concept]"
    description: "[Description of what this represents in your system]"
    related_to: []
  - name: "[Concept]"
    description: "[Description of what this represents in your system]"
    related_to: []
  - name: "[Concept]"
    description: "[Description of what this represents in your system]"
    related_to: []
```
<!-- DATA:domain-concepts:END -->

<!-- DATA:business-rules:START -->
```yaml
rules:
  - id: "rule_1"
    description: "[Description of the business rule]"
    enforcement: "[How/where this rule is enforced]"
  - id: "rule_2"
    description: "[Description of the business rule]"
    enforcement: "[How/where this rule is enforced]"
  - id: "rule_3"
    description: "[Description of the business rule]"
    enforcement: "[How/where this rule is enforced]"
```
<!-- DATA:business-rules:END -->
<!-- SECTION:architecture:core-concepts:END -->

<!-- SECTION:architecture:integrations:START -->
## External Integrations

<!-- DATA:third-party-services:START -->
```yaml
services:
  - name: "[Service Name]"
    purpose: "[Purpose and how it's used]"
    api_type: "[REST/GraphQL/gRPC/etc]"
    authentication: "[Auth method]"
  - name: "[Service Name]"
    purpose: "[Purpose and how it's used]"
    api_type: "[REST/GraphQL/gRPC/etc]"
    authentication: "[Auth method]"
```
<!-- DATA:third-party-services:END -->

<!-- DATA:internal-services:START -->
```yaml
internal:
  - name: "[Service Name]"
    purpose: "[Purpose and how it's used]"
    protocol: "[Communication protocol]"
  - name: "[Service Name]"
    purpose: "[Purpose and how it's used]"
    protocol: "[Communication protocol]"
```
<!-- DATA:internal-services:END -->

<!-- DATA:apis:START -->
```yaml
apis:
  - name: "[API Name]"
    description: "[Description and usage]"
    version: "[Version]"
    endpoints: []
  - name: "[API Name]"
    description: "[Description and usage]"
    version: "[Version]"
    endpoints: []
```
<!-- DATA:apis:END -->
<!-- SECTION:architecture:integrations:END -->

<!-- SECTION:architecture:organization:START -->
## Code Organization

<!-- DATA:directory-structure:START -->
```yaml
structure:
  - path: "src/"
    contains:
      - path: "[layer1]/"
        description: "[Description of this layer]"
        subdirs:
          - path: "[component]/"
            description: "[Description]"
          - path: "[component]/"
            description: "[Description]"
      - path: "[layer2]/"
        description: "[Description of this layer]"
        subdirs:
          - path: "[component]/"
            description: "[Description]"
          - path: "[component]/"
            description: "[Description]"
      - path: "[layer3]/"
        description: "[Description of this layer]"
      - path: "shared/"
        description: "Shared utilities and helpers"
      - path: "config/"
        description: "Configuration files"
      - path: "examples/"
        description: "Reference implementations"
```
<!-- DATA:directory-structure:END -->

<!-- DATA:module-organization:START -->
```yaml
organization_patterns:
  - type: "Feature-based"
    description: "Organize by features (recommended for larger projects)"
    when_to_use: "When features are well-defined and independent"
  - type: "Layer-based"
    description: "Organize by architectural layers"
    when_to_use: "When following strict architectural patterns"
  - type: "Domain-based"
    description: "Organize by business domains"
    when_to_use: "When using Domain-Driven Design"
```
<!-- DATA:module-organization:END -->
<!-- SECTION:architecture:organization:END -->

<!-- SECTION:architecture:data-flow:START -->
## Data Flow

<!-- WORKFLOW:request-lifecycle:START -->
```yaml
request_flow:
  - step: 1
    name: "Entry Point"
    description: "[How requests enter your system]"
    components_involved: []
  - step: 2
    name: "Processing"
    description: "[How they're processed]"
    components_involved: []
  - step: 3
    name: "Response Generation"
    description: "[How responses are generated]"
    components_involved: []
  - step: 4
    name: "Response Delivery"
    description: "[How they're returned to the client]"
    components_involved: []
```
<!-- WORKFLOW:request-lifecycle:END -->

<!-- DATA:data-storage:START -->
```yaml
storage:
  primary_database:
    type: "[Type]"
    purpose: "[Purpose]"
    connection_pool: true
  cache_layer:
    type: "[Type if applicable]"
    purpose: "[Purpose if applicable]"
    ttl: "[Time to live]"
  file_storage:
    type: "[Type if applicable]"
    purpose: "[Purpose if applicable]"
    location: "[Local/Cloud]"
  message_queue:
    type: "[Type if applicable]"
    purpose: "[Purpose if applicable]"
    retention: "[Message retention policy]"
```
<!-- DATA:data-storage:END -->
<!-- SECTION:architecture:data-flow:END -->

<!-- SECTION:architecture:communication:START -->
## Communication Patterns

<!-- DATA:internal-communication:START -->
```yaml
internal:
  patterns:
    - type: "[Synchronous/Asynchronous]"
      description: "[How components communicate]"
      use_cases: []
    - type: "Event-driven"
      description: "[Event patterns if applicable]"
      event_bus: "[Technology used]"
```
<!-- DATA:internal-communication:END -->

<!-- DATA:external-communication:START -->
```yaml
external:
  patterns:
    - type: "[REST/GraphQL/gRPC/etc.]"
      description: "[API patterns]"
      authentication: "[Auth method]"
      rate_limiting: "[Rate limit strategy]"
```
<!-- DATA:external-communication:END -->
<!-- SECTION:architecture:communication:END -->

<!-- SECTION:architecture:security:START -->
## Security Considerations

<!-- DATA:auth-security:START -->
```yaml
authentication:
  method: "[JWT/OAuth/Sessions/etc.]"
  token_expiry: "[Expiry time]"
  refresh_strategy: "[How tokens are refreshed]"

authorization:
  model: "[RBAC/ABAC/etc.]"
  permission_check: "[Where permissions are checked]"
  
data_security:
  encryption_at_rest: "[Yes/No and method]"
  encryption_in_transit: "[Yes/No and method]"
  sensitive_data_handling: "[How sensitive data is handled]"
  compliance: "[GDPR/HIPAA/etc.]"
```
<!-- DATA:auth-security:END -->
<!-- SECTION:architecture:security:END -->

<!-- SECTION:architecture:performance:START -->
## Performance & Scalability

<!-- DATA:caching-strategy:START -->
```yaml
caching:
  levels:
    - level: "Application"
      what_cached: "[Data types cached]"
      ttl: "[Time to live]"
    - level: "Database"
      what_cached: "[Query results]"
      ttl: "[Time to live]"
  invalidation:
    strategy: "[TTL/Event-based/Manual]"
    description: "[How cache is invalidated]"
```
<!-- DATA:caching-strategy:END -->

<!-- DATA:scaling-approach:START -->
```yaml
scaling:
  horizontal:
    enabled: "[Yes/No]"
    auto_scaling: "[Yes/No]"
    metrics: "[CPU/Memory/Request rate]"
  vertical:
    enabled: "[Yes/No]"
    limits: "[Max resources]"
  load_balancing:
    strategy: "[Round-robin/Least connections/etc.]"
    health_checks: "[How health is determined]"
  database_scaling:
    read_replicas: "[Yes/No]"
    sharding: "[Yes/No]"
    strategy: "[Scaling strategy]"
```
<!-- DATA:scaling-approach:END -->
<!-- SECTION:architecture:performance:END -->

<!-- SECTION:architecture:development:START -->
## Development Guidelines

<!-- DATA:design-principles:START -->
```yaml
principles:
  - name: "[SOLID/DRY/KISS/etc.]"
    description: "[How it's applied]"
  - name: "[Principle]"
    description: "[How it's applied]"
  - name: "[Principle]"
    description: "[How it's applied]"
```
<!-- DATA:design-principles:END -->

<!-- DATA:coding-standards:START -->
```yaml
standards:
  - rule: "Repository pattern for data access"
    reason: "Separation of concerns"
  - rule: "Dependency injection"
    reason: "Better testability"
  - rule: "Business logic separate from infrastructure"
    reason: "Clean architecture"
  - rule: "Unit tests for all business logic"
    coverage_target: "[Percentage]"
  - rule: "Document complex algorithms"
    format: "[Documentation format]"
```
<!-- DATA:coding-standards:END -->

<!-- DATA:api-design:START -->
```yaml
api_standards:
  versioning:
    strategy: "[URL/Header/Accept]"
    format: "[v1, v2, etc.]"
  error_handling:
    format: "[Error response format]"
    status_codes: "[Which codes are used]"
  request_response:
    format: "[JSON/XML/etc.]"
    validation: "[How requests are validated]"
```
<!-- DATA:api-design:END -->
<!-- SECTION:architecture:development:END -->

<!-- SECTION:architecture:deployment:START -->
## Deployment Architecture

<!-- DATA:environments:START -->
```yaml
environments:
  - name: "Development"
    description: "[Description]"
    url: "[URL if applicable]"
    deployment: "[Manual/Auto]"
  - name: "Staging"
    description: "[Description]"
    url: "[URL if applicable]"
    deployment: "[Manual/Auto]"
  - name: "Production"
    description: "[Description]"
    url: "[URL if applicable]"
    deployment: "[Manual/Auto]"
```
<!-- DATA:environments:END -->

<!-- DATA:infrastructure:START -->
```yaml
infrastructure:
  hosting:
    provider: "[AWS/GCP/Azure/etc.]"
    services: "[Services used]"
    regions: "[Deployment regions]"
  ci_cd:
    pipeline: "[GitHub Actions/Jenkins/etc.]"
    stages: "[Build/Test/Deploy]"
    triggers: "[Push/PR/Manual]"
  monitoring:
    apm: "[Application Performance Monitoring tool]"
    logging: "[Logging solution]"
    alerting: "[Alerting strategy]"
```
<!-- DATA:infrastructure:END -->
<!-- SECTION:architecture:deployment:END -->

---
*This document describes the technical architecture of the project. Update it as architectural decisions are made or changed.*