TrustChain — Trust-Based Community Trading Platform
TrustChain is a trust-first, invite-only platform where communities discover verified partners to exchange USD/USDT for local currency. It combines secure authentication, a deterministic order-lifecycle engine, Bayesian trust scoring, and near-real-time messaging into a single system—built on a production-grade FastAPI backend and a React 19 frontend, deployed on scalable AWS infrastructure that supports large, active communities.
My Key Contributions
Secure Auth & Session System
Engineered a hardened authentication layer with JWT access tokens and rotating refresh tokens stored in HttpOnly cookies, automatic token-reuse and breach detection that revokes an entire session family on compromise, and bcrypt password hashing—built to keep thousands of concurrent sessions safe.
Order Lifecycle Engine
Designed a deterministic 9-state order state machine with a full audit trail of every transition, dual-party confirmations, auto-expiry timers, and community-scoped multi-tenant isolation enforced at the database level so data never leaks across communities.
Trust & Reputation System
Built a Bayesian trust-scoring and completion-rate reputation engine that recomputes idempotently from order history, powering a ranked partner-discovery search that surfaces the most reliable counterparties first.
Inside the Platform
Invite-Only Communities
Members vote to admit newcomers, so trust is built into the network itself—no KYC and no middleman standing between traders.
Peer-to-Peer Trade Discovery
Users post buy and sell offers with live rates and linked payment methods, and a ranked search surfaces the best-matched partners in their communities.
Order Chat & Confirmations
Both sides coordinate payment over an order-scoped chat and confirm the outcome; mutual confirmation closes the deal, while disagreements are automatically flagged as contested.
Offline Demo Mode
A fully working product demo runs entirely in the browser from IndexedDB with zero backend calls, so anyone can explore the whole experience instantly.
Tech Stack
A FastAPI backend built on clean architecture and a React 19 frontend, deployed on AWS with automated CI/CD, TLS, and full Prometheus + Grafana observability—engineered to scale to large, active communities.
Core & API
Data
Frontend
Auth & Security
Cloud & Infra
CI/CD
Observability
Sync & Notifications
Are you interested?
Let's work together on your project.