TrueLayer + Stripe Demo App

Objective

The goal of this project was to build an interactive demo application that showcases the integration of the TrueLayer Open Banking API, the Stripe payment system, and an automated client assessment module.
The application demonstrates how third-party payment data and real bank transactions can be combined, displayed, and analyzed to produce a financial risk assessment.

Key Features

1. Bank Data Retrieval (TrueLayer)

• User authentication in a sandbox environment.
• Listing bank accounts and displaying account details: balances and transaction history.

2. Sandbox Stripe Payment

• The user selects a bank account and a demo product.
• A Stripe Checkout Session is initiated using sandbox card details.
• Upon successful payment, a mock transaction is added to the chosen account.

3. Mock Transaction Injection

• Stripe session details are fetched.
• A transaction is generated following the TrueLayer transaction format.
• Mock transactions are stored in localStorage.
• The transaction list displays both real and mock entries combined.

4. Automated Client Assessment (KYC/KYB Demo)

• The system analyzes transactions (real + mock data).
• Key evaluation metrics include:
  • 3-month average income and expenses
  • Expense-to-income ratio
  • Expense volatility (stability)
  • Ratio of high-risk transactions (e.g., gambling, payday loans)
  • Frequency of high-value payments
• Results are displayed with visual badges and detailed reasoning.
• Includes a simulated processing sequence (e.g., “Analyzing cashflow”, “Detecting recurring income”) to enhance user experience.

Technology Stack

• Frontend: Next.js (App Router), React, Tailwind CSS, Shadcn UI
• Backend: Next.js API Routes (proxy for TrueLayer and Stripe APIs)
• APIs:
  
  • TrueLayer Sandbox API – banking data
  • Stripe Test Mode API – sandbox payments
• Data Storage:
  
  • Real banking data – via TrueLayer
  • Mock transactions – localStorage
• Analysis Logic: Frontend transaction evaluation function (calculateScore())

User Flow

• Log in via the TrueLayer sandbox bank.
• Select a bank account.
• Initiate a Stripe payment for the demo product.
• On successful payment → insert mock transaction
• Transaction list updates (real + mock)
• Automated client assessment runs based on transaction history.
• The Assessment Panel displays detailed results and reasoning.