The Ultimate Privacy-First Financial Engine
Cuan empowers you with an ultra-fast, local-first finance tracker. Built on browser-embedded PostgreSQL and WASM, your financial data never leaves your device unencrypted.
Currently heavily tested and verified on the latest Google Chrome and Brave browsers (Desktop & Mobile).
Engineered for Privacy & Speed
Traditional finance apps store your records on centralized cloud databases. Cuan embeds a full SQL database locally inside your browser sandbox.
Local-First SQL
Browser-embedded PostgreSQL database running on WebAssembly with high-speed OPFS persistence. Your app, your data.
Zero-Knowledge
All financial records and receipt images are encrypted locally using AES-GCM before storage. We can never read your data.
Native Multi-Currency
Date-matched multi-currency aggregation with precise daily, weekly, and monthly budget enforcement.
How Local-First Privacy Works
1. Local Execution
PGlite runs PostgreSQL natively in your browser thread via WASM & OPFS.
2. Client Encryption
Data & receipt attachments are sealed locally with AES-GCM before transport.
3. Zero-Knowledge Sync
Relay server only stores encrypted binary blobs. Only your devices hold the keys.
Traditional Cloud Apps vs. Cuan
Why local-first architecture is the future of personal data sovereignty.
| Dimension | Traditional Cloud Apps | Cuan Local-First |
|---|---|---|
| Data Storage | Stored plain on central 3rd-party servers | 100% on your device (Browser OPFS) |
| Privacy & Encryption | Company has access to your full financial ledger | Zero-knowledge AES-GCM client encryption |
| Offline Resilience | Broken or read-only without constant internet | 100% functional offline with auto delta sync |
| Query Latency | 200ms – 800ms network round-trip delays | 0ms instant execution via in-memory WASM SQL |
| Data Portability | Proprietary formats and vendor lock-in | Standard PostgreSQL dump anytime |
Inspectable & Verifiable
Closed native app store binaries often bundle opaque analytics and ad trackers. With Cuan, you can open browser DevTools to verify that zero unencrypted bytes leave your device.
Full PostgreSQL Engine
Runs identical PGlite WASM SQL queries across Mac, Windows, Linux, Android, and iOS browsers—never watered-down mobile SQLite wrappers.
1-Click Install & PWA
Instant home screen installation with no 200MB app store downloads, zero platform gatekeeping, and full offline persistence.
Plans & Pricing
No credit card required. Free tier is yours forever.
Free Tier
MOST POPULARPerfect for individuals wanting full local ownership of their financial data.
- 100 MiB Storage
- 3 Active Devices
- Local Encryption
- 100% Offline Functional
Pro Tier
IN DEVELOPMENTPro features are in active development. Fill out the interest form to help us gauge demand and accelerate release.
- Everything in Free Tier, plus:
- 1024 MiB Storage
- 10 Active Devices
- Export to Excel
- Priority Support
Frequently Asked Questions
What does “Local-First” mean?
It means your browser is the primary database. Cuan doesn't fetch your transactions from a remote server every time you load the app; they live directly on your device using PGlite. The server only exists to sync data seamlessly across your devices.
Is my financial data secure?
Yes. We use zero-knowledge encryption (XChaCha20-Poly1305) to ensure your data is encrypted locally before it ever leaves your device. The server only stores encrypted blobs and cannot read your financial information.
Will Cuan work offline?
Absolutely. Because Cuan is offline-first, you can open it, log expenses, and view reports completely disconnected from the internet. The app will automatically sync in the background once you are back online.
Which browsers are supported?
Cuan is currently heavily tested and verified on the latest Google Chrome and Brave browsers (Desktop & Mobile). Support for other WebAssembly/OPFS-compatible browsers is continuously expanding.
Why not build a native mobile app instead?
Closed native app binaries distributed through app stores are black boxes that often bundle opaque tracking SDKs, trap your financial records inside proprietary operating system silos, and are subject to arbitrary store gatekeeping and paywalls.
By building Cuan with WebAssembly, PGlite, and PWA capabilities:
- Inspectable & Verifiable: You can open browser DevTools and inspect network traffic to prove 0 unencrypted bytes ever leave your device.
- Universal Relational SQL: The exact same enterprise-grade PostgreSQL engine runs across Mac, Windows, Linux, Android, and iOS browsers.
- Frictionless Ownership: Install in 1 click to your home screen without a 200MB download, and export standard PostgreSQL dumps anytime.