Alex Chen

Built Fraud Detection at Scale

Stripe's payments platform needed advanced fraud prevention to protect millions of daily transactions. As Senior Software Engineer, Alex was tasked with leading the payments integration team to build real-time detection capabilities. He architected and deployed fraud detection pipelines leveraging machine learning models and streaming data infrastructure. The system processed 10M+ transactions daily with a 40% reduction in fraudulent charges.

Supercharged Collaborative Editing

Figma's growing user base of 4M+ designers demanded seamless real-time collaboration features. Alex joined the collaborative editing team to improve the core multiplayer editing experience. He developed new WebSocket-based collaboration features and profiled network bottlenecks to optimize performance. WebSocket performance improved by 40%, enabling smoother real-time co-editing for millions of users.

Delivered 15+ Client Projects

Multiple startups and small businesses needed custom web solutions but lacked in-house engineering talent. As a freelance web developer, Alex was responsible for end-to-end delivery of tailored applications. He built full-stack applications using React and Node.js, managing client relationships and project timelines independently. Successfully delivered 15+ projects, helping clients launch products and grow their digital presence.