Architecture Decision Records (ADRs)

This directory contains Architecture Decision Records (ADRs) that document important architectural decisions made during the development of Zixly.

ADR Format

Each ADR follows this structure:

• Title: Clear, descriptive title
• Status: Proposed, Accepted, Deprecated, Superseded
• Context: What is the issue that we’re seeing that is motivating this decision?
• Decision: What is the change that we’re proposing or have made?
• Consequences: What becomes easier or more difficult to do because of this change?

ADR Index

• ADR-001: Multi-Tenant Architecture
• ADR-003: Real-Time Data Strategy
• ADR-004: Mobile App Architecture
• ADR-005: Open-Source Strategy
• ADR-006: Kubernetes Pipeline Orchestration
• ADR-007: Webhook Event-Driven Pipeline Architecture
• ADR-008: Local Docker Compose First Strategy
• ADR-009: LocalStack + Terraform Phase

Business Context

Zixly is a DevOps automation platform for Brisbane businesses.

This platform:

• Provides webhook-triggered data analysis pipelines
• Demonstrates cloud-native infrastructure patterns
• Showcases Docker, Kubernetes, Terraform, and AWS expertise
• Is open-source for portfolio demonstration and reuse purposes

Decision Categories

Architecture Decisions

• Multi-tenant vs Single-tenant: Internal operations platform
• Pipeline orchestration: Kubernetes Jobs vs other orchestration tools
• Event architecture: Webhook-driven vs polling-based pipelines
• Local-first strategy: Docker Compose MVP before cloud deployment
• Infrastructure as Code: Terraform with LocalStack for local development
• Real-time data strategy: WebSocket vs polling approaches
• Mobile app architecture: React Native vs native development

Technology Decisions

• Database choice: PostgreSQL with Supabase
• Authentication: Supabase Auth vs custom solution
• Deployment: Docker Compose → Kubernetes → AWS EKS progression
• Monitoring: Prometheus + Grafana observability stack
• Queue System: Redis/Bull vs AWS SQS for job processing
• Infrastructure: LocalStack for local AWS emulation

Business Decisions

• Open-source strategy: Community engagement and contribution
• Internal operations focus: Service business optimization
• Dogfooding approach: Authentic expertise demonstration
• Competitive positioning: Unique market differentiation

Decision Process

1. Identify Decision Need

• Architecture review identifies decision points
• Business requirements drive technology choices
• Implementation challenges require solutions
• Performance or security concerns arise

2. Research Options

• Evaluate multiple approaches
• Consider trade-offs and consequences
• Research best practices and patterns
• Consult with team and stakeholders

3. Make Decision

• Document rationale and context
• Record decision and consequences
• Communicate to team
• Update implementation plans

4. Review and Update

• Regular review of decisions
• Update when context changes
• Deprecate when superseded
• Learn from consequences

Decision Principles

Technical Principles

• Simplicity: Prefer simple, elegant solutions
• Maintainability: Choose maintainable approaches
• Performance: Optimize for performance
• Security: Prioritize security and compliance

Business Principles

• DevOps Automation: Focus on Brisbane tech market
• Open-Source: Enable portfolio demonstration and reuse
• Cloud-Native Patterns: Demonstrate modern infrastructure practices
• Competitive Advantage: Local Brisbane DevOps expertise

Implementation Principles

• Fail-Fast: Throw meaningful exceptions immediately
• Type Safety: TypeScript strict mode across entire stack
• Multi-Tenancy: Enforce tenant_id scoping in all queries
• Documentation: Comprehensive documentation for all decisions

Document Version: 1.0
Last Updated: 2025-01-27
Owner: Technical Architecture
Review Cycle: Quarterly