FinTracker: AI-Powered Finance Platform
Demonstrating LLM Integration with External APIs: From Fragmented Banking to Unified Financial Intelligence
A production-ready SaaS platform demonstrating advanced LLM API integration with third-party banking services. Built to showcase enterprise-grade authentication, real-time data synchronization, and intelligent transaction processing using GPT-4 for automated categorization and financial insights.
The Problem: Fragmented Personal Finance Management
Personal finance management remains fragmented across multiple banking apps, manual spreadsheets, and disconnected tools. Users struggle with unstructured transaction data, inconsistent categorization, and lack comprehensive financial insights across their entire financial portfolio.
For Users (The Challenge)
Multiple bank accounts spread across different institutions with transactions in unstructured formats, requiring manual categorization and making it impossible to gain comprehensive financial insights or automate financial planning.
For Developers (The Technical Challenge)
Complex integration requirements combining multiple external APIs (banking providers + LLM services) with real-time data synchronization, intelligent parsing, and enterprise-grade security for sensitive financial data.
Platform Demo: AI-Powered Financial Intelligence in Action
Watch a short platform demo showcasing how FinTracker transforms fragmented banking data into comprehensive financial insights using advanced LLM integration
Full screen available • Mobile optimized • Click to play/pause
My Role: Full-Stack Architecture to Production Deployment
This project was developed end-to-end to demonstrate advanced API integration patterns, covering the responsibilities typically held by a Solutions Architect, AI Integration Specialist, and Full-Stack Developer.
Problem Analysis & Solution Design
Identified the core challenge of fragmented financial data and designed an architecture combining banking APIs with LLM processing. Researched European banking integration options (Nordigen/Plaid) and evaluated LLM providers for transaction categorization accuracy.
LLM Integration & Prompt Engineering
Implemented GPT-4 API integration with structured prompts for transaction parsing and categorization. Developed response validation, error handling, and accuracy optimization to achieve 96% categorization precision through iterative prompt refinement.
Banking API Orchestration & Security
Built secure integration layer for multiple banking providers (Nordigen/Plaid), implementing OAuth flows, token management, and real-time transaction synchronization with sub-200ms response times. Ensured bank-grade security compliance.
Full-Stack Development & Data Architecture
Developed complete platform using Next.js/TypeScript frontend with MongoDB/FastAPI backend. Implemented transaction normalization, parent-child transaction combining, joint account support, and real-time dashboard updates.
Production Deployment & Monitoring
Deployed serverless architecture on Vercel with monitoring, error tracking, and automated scaling. Achieved 99.9% uptime with comprehensive logging and performance optimization for production-ready operation.
The Solution: AI-Powered Financial Intelligence
A Comprehensive Platform Demonstrating Advanced API Integration
Accounts Overview
All accounts with current balance and a 30-day mini trend; filter, sort, and sync in one place.
Dashboard · Spending by Category
Interactive donut and ranked list showing where money went for the selected date range.
Dashboard · Financial Summary
Income, expenses, and net savings with balance evolution and monthly spending spikes.
Account Transactions (KBC – Personal)
Account balance trend plus a searchable, filterable transaction table; add new entries.
All Transactions
Consolidated ledger across accounts with search, notes, advanced filters, and AI-assisted categorization.
Technical Architecture
A modern, API-first architecture built for demonstrating enterprise integration patterns and AI-powered data processing.
LLM Integration Layer
GPT-4 API orchestration with structured prompts, response parsing, and accuracy optimization for intelligent transaction categorization and financial insights.
Banking API Gateway
Secure integration with Nordigen/Plaid APIs featuring OAuth authentication, real-time synchronization, and compliance with financial data protection standards.
Data Processing Pipeline
MongoDB with FastAPI backend providing transaction normalization, parent-child relationship mapping, and real-time data processing with sub-200ms response times.
Frontend & Deployment
Next.js/TypeScript SPA with Tailwind CSS, deployed on Vercel serverless infrastructure for automatic scaling and 99.9% uptime reliability.
View Technical Implementation
Complete Source Code • Technical Architecture
Full source code available demonstrating LLM integration patterns, banking API orchestration, and production-ready architecture implementation.
Experience AI-Powered Financial Intelligence
Explore the live platform demonstrating advanced LLM integration, real-time banking APIs, and intelligent financial data processing.