Overview
A secure, full-stack fintech application that bridges the gap between banking data and payment processing using Plaid and Dwolla.
Scope
Full Stack Architecture, API Integration, Security Implementation
Tech Stack
Languages: TypeScript, HTML/CSS, SQL
Frontend: React, Next.js, Tailwind CSS, Shadcn UI, Zustand, React Hook Form, Chart.js
Backend: Bun, Express, Prisma, Plaid API, Dwolla API
Databases: PostgreSQL
Developer Tools: Git/GitHub, Docker, Sentry, ESLint, Concurrently
Challenge
The primary challenge was orchestrating a secure, atomic handshake between two complex financial APIs. Plaid for reading data and Dwolla for moving money, while strictly adhering to compliance and security standards. This required synchronizing local transaction records with remote banking state to ensure accuracy, implementing AES-256 encryption for PII at rest, and managing distinct sandbox configurations for multiple third-party services without leaking credentials.
Objective
The objective was to architect and build a robust Fintech MVP that safeguards sensitive user data while providing a frictionless modern banking experience. The goal was to go beyond simple API connections to create a scalable architecture capable of handling real-world financial workflows, including real-time account verification, balance checks, and legally compliant money transfers.
Results
Interlock delivered a polished, production-ready MVP that allows users to securely onboard, instantly link real-world bank accounts, and execute ACH transfers with immediate feedback. The final product features a 100% TypeScript codebase for maintainability and utilizes a high-performance Bun/Express backend to handle webhooks and concurrent API requests with minimal latency.