What is Local-First Architecture?
Local-First Architecture is a software design pattern where data is stored and processed on the user's device first, with optional cloud sync. This ensures privacy, offline functionality, and user data sovereignty.
Core Principles
- Privacy is an engineering choice: not a legal promise.
- Limited-scope processor posture: reduces SOC 2 audit perimeter and UK DPA/GDPR burden.
- Stateless Floor: standardizes data while remaining regulatory-agnostic.
Citation: Salford Seed Deck v4.1, Slide 11 (Regulatory Posture).
Why does it matter?
Traditional cloud-first apps store all your data on their servers. This creates privacy risks, vendor lock-in, and dependency on internet connectivity. Local-first architecture puts you in control.
Real-World Example: Pocket Portfolio
Pocket Portfolio uses local-first architecture:
- Your portfolio data: Stored in your browser (localStorage/IndexedDB)
- CSV parsing: Done entirely client-side (no server uploads)
- Price data: Fetched via API but analyzed locally
- Optional sync: Google Drive sync available, but not required
Result: We never see your Net Worth. You own your data completely.
Benefits of Local-First
- Privacy: Your sensitive data never leaves your device
- Offline: Works without internet connection
- Speed: No network latency for local operations
- Ownership: You control your data, not the vendor
- No Lock-In: Export your data anytime in standard formats
- Security: Reduced attack surface (no central database of user data)
Key Takeaways
- Local-first = privacy-first—your data stays on your device.
- Cloud is optional—used for sync/backup, not core functionality.
- You own your data—export anytime, no vendor lock-in.
- Works offline—no internet required for core features.
Learn More About Our Architecture
Read why we built Pocket Portfolio with local-first principles:
Read Architecture Guide →