David Listello

Looking for a production-grade, scalable full-stack web application or an AI-powered SaaS platform? With **20 years of enterprise experience in Cloud High-Availability, DevOps, and SRE**, I build robust, secure, and lightning-fast digital solutions that go far beyond basic templates.
Whether you need a complex fintech platform like SpendWise (with group expense splitting and real-time analytics) or an advanced AI workflow, I deliver clean architecture from database to UI.
**My Core Tech Stack & Expertise:**
* **Backend & Core APIs:** Java 25 / Spring Boot for bulletproof enterprise systems; Python 3.14 (FastAPI) for high-performance microservices.
* **Databases & Data Science:** Advanced PostgreSQL modeling for intricate relational data (ledgers, multi-user transactions) and data science pipelines.
* **Advanced AI & Machine Learning:** Specialized in **LLMs, RAG (Retrieval-Augmented Generation) pipelines, Diffusion models, and custom OCR integrations** to give your app true intelligence.
* **Frontend & UI/UX:** Modern, responsive interfaces built with React, Vite, Tailwind CSS, and interactive charting libraries for stunning user experiences.
* **Production Readiness:** Secure authentication, robust error handling, automated CI/CD pipelines, and cloud-native scalability.

**Why Work With Me?**
* **20 Years of Engineering Rigor:** Enterprise-level code quality, security, and bulletproof uptime architecture.
* **End-to-End Ownership:** Seamless integration of complex AI microservices with high-performance relational backends and sleek frontends.
* **Clear Communication:** Fast turnaround, transparent milestones, and a focus on turning your vision into a market-ready product
Let's bring your SaaS or web app vision to life. Send me a message to discuss your project roadmap today!