Mellow Nova

Your personal financial intelligence layer. 100% on-device. No servers. Your data stays yours.

A mobile app (Expo / React Native) that ingests Indian bank SMS and PDF statements, builds a complete financial picture, and applies real mathematical models to help you make smart decisions about your money.

Design principles

1. Accuracy over speed — never guess when you can verify. Every balance carries a confidence tier.
2. Financial robustness — real math (time value of money, linear programming, amortization, Markov chains), not heuristics.
3. Engineering reliability — pure functions, typed interfaces, deterministic outputs for the same inputs.
4. Extensibility — new banks, models, and data sources slot in without touching existing code.
5. Privacy by default — all computation on-device. No network calls, no telemetry.

How it works

DATA LAYER
  SMS XML ─┐
           ├─▶ Ingestion pipeline ─▶ WatermelonDB (SQLite)
  PDF stmt ─┘   (parse, classify, normalize, dedup)

INTELLIGENCE LAYER  (pure functions, no side effects)
  Balance tracker · Cash-flow forecaster · Debt optimizer (LP solver)
  Categorizer · Recurring detector · Loan prepayment simulator
  Credit optimizer · Emergency fund calc · Scenario / Monte Carlo

PRESENTATION LAYER
  Expo / React Native — Dashboard · Insights · Decisions · Alerts

The intelligence engines are all pure functions: given inputs, they produce deterministic outputs with no database access or side effects.

Tech stack

TypeScript · Expo · React Native · WatermelonDB (SQLite) · NativeWind (Tailwind) · Reanimated

Getting started

npm install
npx expo start

Status

Active development. Local-first by design — no data leaves your device.

License

See LICENSE.