Personal details
Andres R.
Technical skills
About
Senior Full-Stack Developer with over 8 years of experience building real-world web applications and scalable platforms, including AI-driven products. I work across the stack using Python, Node.js, React, and FastAPI, with hands-on experience designing and shipping systems that integrate modern language models and retrieval-based architectures. I am comfortable owning technical decisions, balancing performance and cost, and taking projects from early design through production release. I have deployed and maintained cloud-native systems using CI/CD pipelines, Docker, and Kubernetes, and enjoy working closely with product, design, and engineering teams in fully remote environments to deliver reliable, user-focused solutions.
- Hands-on experience with WebSockets in real-time applications, including chat systems and live dashboard updates, enabling seamless server-to-client data streaming without polling.
- Built real-time features using persistent connections to ensure instant data synchronization across clients, improving responsiveness and user experience.
- Implemented WebSocket solutions in a real-time inventory management system at LendingUSA, delivering live updates of stock levels across multiple users and devices.
- Leveraged Socket.IO (Node.js) to manage connections, reconnection logic, and message broadcasting to multiple clients.
Work Experience
- Architected and developed a full-stack AI-powered bid-matching platform using Node.js, MongoDB, and React, deployed on DigitalOcean with a complete CI/CD pipeline implementation.
- Implemented an AI document-parsing system using instructor.js for LLM orchestration and Zod for structured output validation, comparing top-tier and lightweight models across providers (GPT-4/3.5, Claude Opus/Haiku, Gemini Pro/Flash, Grok).
- Conducted comprehensive cost-benefit analyses of LLM models and vector store solutions (OpenAI, Ragie, Google Vertex AI, and in-house), providing data-driven recommendations that informed key architectural decisions.
- Designed the complete software architecture in Miro, establishing system blueprints for backend services, AI integration, and data flow across the platform.
- Built co-pilot chat functionality with persistent message storage and a single-thread-per-opportunity architecture, integrating CopilotKit with a defined RAG architecture and backend actions to enable users to extract useful data.
- Developed a document-scraping pipeline using Playwright with smart bot-detection bypass techniques (stealth and proxy), handling complex formats including ZIP files and image-based documents.
- Built frontend components in React based on Lovable-generated code, resolving frontend/backend inconsistencies and API schema duplication issues.
- Led technical evaluations and selected Gemini 2.5 Flash as the most cost-effective model with sufficient quality for production parsing, transitioning the project from the research phase into full production build mode.
- Developed and maintained interactive, user-friendly geospatial dashboards for real-time energy consumption and grid performance visualization using React.js.
- Designed and implemented responsive, mobile-first UI components that improved user engagement by 25%.
- Integrated data visualization tools like D3.js and Chart.js to display complex energy metrics, providing insights into grid performance and efficiency.
- Worked closely with backend engineers to consume RESTful APIs, ensuring seamless data flow and synchronization between frontend and backend systems.
- Optimized web application performance, reducing load times by 30% through code splitting, lazy loading, and image optimization techniques.
- Collaborated with UX/UI designers to create wireframes and mockups that enhanced the user experience and simplified complex data interactions.
- Implemented state management solutions using Redux, improving application performance and maintainability.
- Conducted thorough unit and integration testing with Jest and React Testing Library to ensure high-quality, bug-free code.
- Participated in Agile ceremonies including sprint planning, retrospectives, and daily stand-ups to ensure timely delivery of features.