Paypal

• 

  Axiom99

Inspiration

Axiom99 was born out of a fundamental desire to make digital payments safer, faster, and accessible to everyone without friction. While PayPal has transformed the global digital economy, small merchants and peer-to-peer users still face challenges with dynamic fraud, multi-currency settlement latency, and real-time transaction verification. Inspired by the core principle of an axiom—a truth that is self-evident and unquestioned—we built Axiom99 to serve as an immutable, trustless foundation for modern PayPal transactions.

What it does

Axiom99 enhances the PayPal payment ecosystem by introducing real-time predictive risk scoring, automated smart settlement flows, and seamless cross-border payment routing. Key features include:

• Instant Risk Validation: Evaluates transaction telemetry on-the-fly to assign a real-time trust score before triggering payment execution.
• Automated Dispute Mitigation: Uses transaction metadata and automated verification rules to handle edge-case payment holds before they turn into chargebacks.
• Smart Currency Optimization: Dynamically routes cross-border payments using optimal paths to reduce settlement overhead for international buyers and sellers.

How we built it

We built Axiom99 using a modern, scalable microservice architecture:

• Frontend: Built with React and Tailwind CSS for a sleek, responsive dashboard interface.
• Backend: Node.js / Express server integrated with PayPal Developer APIs (Orders API, Payouts API, and Webhooks).
• AI & Analytics Engine: Python-based model for transaction risk analysis and anomaly detection.
• Database: PostgreSQL for persistent transaction history and Redis for real-time state management.

Challenges we ran into

• Real-time Webhook Synchronization: Managing asynchronous state updates from PayPal webhooks while serving live risk scores to the frontend required precise event-loop handling and redis locking.
• Edge-case Fraud Modeling: Balancing fraud detection without triggering false positives for legitimate high-value or cross-border users.
• API Rate Limits: Optimizing bulk API payload calls to maintain high throughput during simulated high-volume payment spikes.

Accomplishments that we're proud of

• Fully integrating PayPal’s payment lifecycle end-to-end within the tight timeframe of the hackathon.
• Achieving low-latency (<150ms) transaction risk scoring alongside live checkout flows.
• Designing an intuitive UX that gives merchants actionable insights into transaction safety without complex setup.

What we learned

• Deep insights into PayPal's REST APIs, SDKs, and sandbox architecture.
• Best practices for handling edge-case payment states, webhook fallbacks, and multi-currency tokenization.
• How to effectively combine predictive analytics with financial transaction pipelines securely.

What's next for Axiom99 & PayPal

• SDK Integration: Packaging Axiom99 into a plug-and-play middleware library for merchants using PayPal Checkout.
• Biometric Auth Integration: Enhancing checkout speed with passkeys and webauthn validation tied directly to PayPal accounts.
• Expanded Merchant Tools: Adding automated tax calculations and instant multi-currency payout forecasting for international businesses.

Built With

• javascript
• node.js
• paypal
• postgresql
• python
• react
• redis
• talwindcss