Karzan Hashem

I am a Senior Full Stack Engineer with 8+ years building scalable, high-traffic web applications across fintech, marketing, and e-commerce domains. I specialize in React, Next.js (SSR), Node.js, Python, Java, and cloud-native architectures on AWS and Azure. At my current role I developed core product features for a global rewards platform serving over 1M registered users, built backend services for real-time reward attribution using Node.js and FastAPI, and implemented secure payout systems integrating PayPal, Stripe, crypto gateways, and gift card APIs. I have delivered regulatory reporting and digital onboarding platforms, engineered microservices and REST/GraphQL APIs, and contributed to cloud-native CI/CD pipelines. I also implemented observability with Datadog and Sentry, participated in on-call rotations, and used Amplitude to run A/B experiments that informed product decisions. I design AI-driven product features using RAG and LLM integrations for support automation, fraud enrichment, and personalization, and I thrive in cross-functional teams that value data-driven iteration, reliability, and scalable architecture.