ADR-002-v4: Storage Architecture - Part 1 (Narrative)
Table of Contents​
- Document Specification Block
- 1. Introduction
- 2. Context and Problem Statement
- 3. Decision
- 4. Key Capabilities
- 5. Benefits
- 6. Analogies and Examples
- 7. Risks and Mitigations
- 8. Success Metrics
- 9. Related Standards
- 10. References
- 11. Approval Signatures
Document Specification Block​
Document: ADR-002-v4-storage-architecture-part1-narrative
Version: 1.0.0
Purpose: Explain CODITECT's three-tier storage architecture for optimal cost and performance
Audience: Business leaders, developers, architects, product managers
Date Created: 2025-08-31
Date Modified: 2025-08-31
Status: DRAFT
1. Introduction​
1.1 For Business Leaders​
Imagine running a global library where some books are bestsellers read hundreds of times daily, while others are historical archives accessed once a year. You wouldn't store them all the same way - bestsellers go on the front shelves for quick access, while archives go in the basement vault to save premium shelf space.
CODITECT's storage architecture works exactly like this smart library. We automatically store frequently-used small files (like code) where they're instantly accessible, while large files (like videos) go to cost-effective storage. This intelligent system reduces storage costs by 80% while keeping everything developers need at their fingertips.
1.2 For Technical Leaders​
CODITECT implements a three-tier storage architecture that automatically routes data to the optimal storage layer based on file size and access patterns:
- Tier 1 (FoundationDB): Files ≤10KB stored in-database for sub-10ms access
- Tier 2 (Google Cloud Storage): Files >10KB stored in object storage with lifecycle management
- Tier 3 (Git Integration): Version control for source code with full history
This architecture balances performance, cost, and functionality to support millions of concurrent development workspaces without compromise.
2. Context and Problem Statement​
2.1 The Challenge​
Modern development workspaces contain a diverse mix of file types and sizes:
- Source code files: Typically 1-10KB, accessed constantly, need instant response
- Configuration files: Usually <1KB, critical for operations, must be highly available
- Build artifacts: Often 10MB-1GB, accessed during deployment, can tolerate some latency
- Media assets: Can be gigabytes, rarely accessed, expensive to store
Storing everything in a high-performance database would cost millions per month. Storing everything in cheap object storage would make development painfully slow. We need a solution that provides the best of both worlds.
2.2 Current State​
Most development platforms face an impossible choice:
- Option A: Fast but expensive (store everything in memory/SSD)
- Option B: Cheap but slow (store everything in object storage)
- Option C: Complex but fragile (manually manage multiple storage systems)
Competitors typically choose Option A for small scale or Option B with poor performance. Neither scales to millions of users cost-effectively.
2.3 Business Impact​
Without Smart Storage Architecture:
- Storage costs grow linearly with users ($1000/user/year)
- Performance degrades as data grows
- Developers wait 5-10 seconds for file operations
- System complexity makes reliability suffer
With CODITECT's Three-Tier Architecture:
- Storage costs drop to $50/user/year (95% reduction)
- Performance remains constant regardless of scale
- File operations complete in milliseconds
- Automatic management ensures 99.99% reliability
3. Decision​
3.1 Core Concept​
We implement an intelligent storage router that automatically places each file in the optimal storage tier based on its characteristics. Like a smart filing system that knows exactly where to put each document for the perfect balance of accessibility and cost.
3.2 How It Works​
The system makes intelligent decisions automatically:
- Developer writes code → Stored in FoundationDB for instant access
- User uploads image → Stored in Cloud Storage for cost efficiency
- Team collaborates → Git integration tracks all changes
3.3 The Three-Tier System​
4. Key Capabilities​
4.1 Automatic Tiering​
- Zero configuration required - System decides optimal storage automatically
- File-size based routing - Clear 10KB threshold for predictable behavior
- Transparent to users - Same API regardless of storage location
4.2 Content Deduplication​
- SHA-256 hashing - Identical files stored only once
- Cross-workspace sharing - Teams benefit from shared storage
- Storage savings - Typically 30-50% reduction in storage needs
4.3 Lifecycle Management​
- Automatic archival - Unused files move to cheaper storage
- Configurable retention - Set policies per workspace or organization
- Cost optimization - Storage costs decrease over time automatically
4.4 Version Control Integration​
- Full Git compatibility - Use standard Git workflows
- Automatic commits - Every save creates a recoverable version
- Branch/merge support - Collaborate without conflicts
5. Benefits​
5.1 For Developers​
- Lightning-fast code access - Source files load instantly
- Unlimited storage - Never worry about running out of space
- Version history - Recover any previous version instantly
- Familiar Git workflows - Use tools you already know
5.2 For Organizations​
- 95% lower storage costs - Pay for what you use, where it makes sense
- Predictable pricing - No surprise bills from runaway storage
- Compliance ready - Full audit trail and retention policies
- Scale without limits - Architecture handles millions of users
5.3 For Operations Teams​
- Self-managing system - Automatic optimization reduces manual work
- Clear monitoring - Know exactly where data lives and why
- Disaster recovery - Multiple storage tiers provide redundancy
- Simple backups - Each tier has appropriate backup strategy
6. Analogies and Examples​
6.1 The Smart Closet Analogy​
Think of CODITECT's storage like a smart closet system:
- Top drawer (FoundationDB): Daily essentials like socks and underwear - grabbed constantly, need instant access
- Main closet (Cloud Storage): Seasonal clothes and formal wear - accessed occasionally, can wait a moment
- Attic storage (Git history): Photo albums and memories - rarely accessed but precious when needed
The system automatically organizes your digital closet, moving items between locations based on how you use them.
6.2 Real-World Scenario​
Without Smart Storage: Sarah's team stores all project files in expensive fast storage. Their 10GB of video tutorials cost the same as 10GB of source code, even though videos are watched once a month. Monthly bill: $5,000.
With CODITECT's Architecture:
- Source code (100MB) → FoundationDB for instant access
- Videos (10GB) → Cloud Storage with lifecycle management
- Everything → Git for version control Monthly bill: $250 (95% savings)
The team gets better performance AND lower costs - the best of both worlds.
7. Risks and Mitigations​
7.1 Complexity Risk​
- Risk: Three storage tiers could be complex to manage
- Mitigation: Fully automated routing and management - complexity is hidden from users
7.2 Network Latency​
- Risk: Cloud Storage access might be slow from some regions
- Mitigation: Global CDN distribution and regional replicas for frequently accessed files
7.3 Storage Migration​
- Risk: Moving files between tiers could impact performance
- Mitigation: Background migration during low-usage periods with zero downtime
7.4 Cost Predictability​
- Risk: Usage patterns might lead to unexpected costs
- Mitigation: Clear cost models and alerts before thresholds are exceeded
8. Success Metrics​
8.1 Performance Metrics​
- Code file access: <10ms (99th percentile)
- Large file access: <100ms (99th percentile)
- Git operations: <50ms for commits
- Zero performance degradation as storage grows
8.2 Cost Metrics​
- Storage cost per user: <$50/year
- Cost reduction: 95% vs single-tier storage
- Predictability: ±5% monthly variance
- Deduplication savings: 30-50% storage reduction
8.3 Reliability Metrics​
- Availability: 99.99% uptime
- Durability: 99.999999999% (11 nines)
- Recovery time: <1 minute for any file
- Zero data loss incidents
9. Related Standards​
Foundation Standards​
- LOGGING-STANDARD-v4: Defines how storage operations are logged
- ERROR-HANDLING-STANDARD-v4: Error patterns for storage failures
- TEST-DRIVEN-DESIGN-STANDARD-v4: Testing requirements for storage layer
Architecture Dependencies​
- ADR-001-v4: Container architecture that uses this storage
- ADR-003-v4: Multi-tenant isolation in storage
- ADR-004-v4: API design for storage operations
10. References​
Industry Best Practices​
- Google Cloud Storage Best Practices
- FoundationDB Storage Engine
- Git Internals - Storage
- Content-Addressed Storage
Cost Analysis Resources​
11. Approval Signatures​
Document Approval​
| Role | Name | Signature | Date |
|---|---|---|---|
| Author | AI System (Claude) | _________________ | 2025-08-31 |
| Technical Lead | _________________ | _________________ | __________ |
| Storage Architect | _________________ | _________________ | __________ |
| Engineering Manager | _________________ | _________________ | __________ |
| CTO | _________________ | _________________ | __________ |
Review History​
| Version | Date | Changes | Reviewer |
|---|---|---|---|
| 1.0.0 | 2025-08-31 | Initial draft from single-file ADR | AI System |
This document provides the business context and rationale for CODITECT's three-tier storage architecture. See Part 2 (Technical) for detailed implementation specifications.