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Need a senior architect who can build it, scale it, and make it beautiful, with AI woven through the whole thing instead of bolted on the side? That's what I do. I'm a principal full-stack architect and polyglot engineer, 15+ years taking products from idea to production across fintech, health-tech, cybersecurity, blockchain, defense, and AI. 💡 Work clients know me for: - A $500M real-time fintech trading platform (web + mobile) - A $100M real estate CRM built from scratch; the firm was acquired by Cushman & Wakefield - Solana indexing infrastructure handling $1–3T in daily transaction volume - A live algorithmic quant trading platform running real money on a tier-1 broker - Federated-learning threat detection for an AI cybersecurity platform - Solo-replaced a 10-developer offshore team on a national assistive-communication app 🤖 AI / LLM, where much of my recent work lives: - Production LLM systems with structured outputs, guardrails, and audit logging in regulated fintech - Multi-model pipelines (Claude, Whisper, Gemini, OpenAI, ElevenLabs) chosen deliberately for cost, latency, and accuracy - MCP and agentic tooling, with official Anthropic certifications behind it - A production AI agent and grounded voice-and-chat assistant on frontier models (Gemini, Claude, GPT), with real tool-calling into live equipment data, RAG over the actual manuals, a scorer, and an adversarial grounding eval harness that gates every deploy so it cannot hallucinate to users - Architecting specialized-model training on proprietary field data: fine-tuning small open models (Llama/Qwen) for domain tasks like fault diagnosis and failure prediction, with labeled eval sets and an eval-gated deploy pipeline - The discipline that keeps AI output reliable and affordable in production, not just impressive in a demo 🛠 Stack: - Full-stack: TypeScript/React/Next.js, Node/Deno, Python, Go, Rust, Ruby/Rails, PHP/Laravel - Mobile: Flutter, React Native, Swift, Kotlin - APIs & data: GraphQL, REST, PostgreSQL, MySQL, MongoDB, Redis - Cloud & infra: AWS, GCP, Supabase, Docker/K8s, CI/CD - AI: Claude, Gemini, GPT, MCP, multi-model orchestration - Security: PCI DSS remediation, federated learning, RLS/RBAC, signed webhooks 🎯 Clients hire me when: - They're launching something ambitious and want it architected right the first time - Their legacy codebase is a mess and they need someone who can inherit it and stabilize it fast - They want AI built into the product correctly, by someone who's shipped it in production - They want someone who thinks like an engineer, a strategist, and a founder I also direct and design large-scale sculptures and immersive environments. Fluent in product vision, UX/UI, and creative direction, with experience in Rhino3D, Unity, CAD, TouchDesigner, and Adobe. Request my design portfolio directly if you're curious. 📩 Message me and tell me what you're building. I'll tell you how I'd make it better.

Hi there! I’m a seasoned Full-Stack Software Developer with over 20 years of experience in the tech industry. I specialize in creating robust, scalable, and efficient web applications using modern technologies like React and Amazon Web Services (AWS). My extensive background in both front-end and back-end development allows me to deliver comprehensive solutions that meet my clients' unique needs. What I Offer: Fullstack Development: Expertise in building end-to-end web applications, from designing intuitive frontends to developing powerful backend services. Frontend Excellence: Proficient in React, HTML, CSS, and JavaScript to create responsive and user-friendly interfaces. Backend Mastery: Strong skills in Node.js, Java, and other backend technologies to build scalable and secure server-side applications. Cloud Services: Deep knowledge of AWS services, including EC2, S3, Lambda, RDS, and more, to design and deploy cloud-based solutions. Agile Development: Experience in agile methodologies to ensure efficient project management and timely delivery. Collaboration: Excellent communication skills and a collaborative approach to working closely with clients, designers, and other stakeholders. Key Projects: Oncue: Directed the engineering team to implement Twilio Flex and Dropbox Sign solutions, enhancing customer interaction and streamlining workflows. Healthline Media: Led the development of a new web platform using Node.js and React.js on AWS, improving performance and scalability. Constant Contact: Guided the iOS development team, implemented CI/CD pipelines, and ensured seamless deployment of mobile applications. Skills: Frontend: React, HTML, CSS, JavaScript, TypeScript Backend: Node.js, Java, Spring, SQL, NoSQL Cloud Services: AWS (EC2, S3, Lambda, RDS), GraphQL, Next.js Tools: Git, Docker, Jenkins, Jira, Twilio Methodologies: Agile, Scrum, Continuous Integration/Continuous Deployment (CI/CD) Why Choose Me: I bring a unique blend of technical expertise, project management skills, and a deep commitment to delivering high-quality software solutions. I aim to help you achieve your business objectives by providing reliable, scalable, and user-friendly applications. I am passionate about technology and strive to stay updated with the latest trends and best practices in software development. Let’s work together to bring your ideas to life and drive your projects to success!

🔝Top 1% Expert-Vetted ⭐️ Over $446K earned over 133 different contracts on Upwork I help companies develop data-driven solutions to solve their toughest business challenges. I create robust data scraping & data science programs to help my clients capture leads, monitor prices, identify patterns, make important decisions, and more. Over the past several years, I have worked with dozens of Enterprise clients such as Amazon, Chegg, Spring (formerly TeeSpring), and more. Taking a data-focused approach helps businesses large and small reach new heights. In order for me to help your business grow, I offer the full circle of data-related tasks: 1. Data scraping & extracting - web scraping and extracting unstructured data from internet or APIs 2. Data processing - clean and engineer data to be in the format you need 3. Data loading - store structured data into external source (SQL, S3, Excel, Parquet, Snowflake, etc) 4. Data science - apply state-of-the-art machine learning algorithms to generate high-value insights I combine the many facets of data work into a unified approach, allowing my clients to get clean, organized data that is ready to power their growing business needs. Through my structured approach to generating data-driven solutions, I turn client projects into long-lasting, big-impact work. I can write complex data scraping programs to extract thousands of gigabytes of data. The data scraping software can be combined with other data streams to be fed into data loading and machine learning phases. To realize this return on investment as swiftly as possible, I utilize my large codebase of frameworks and tools to develop time-tested industry-grade solutions. Data is the new gold - let me do the heavy data scraping and data science for you. If it sounds like we may be a good fit, please feel free to message me directly and I would love to chat with you about what you are working on and how I can add the most value. Thank you!

⭐⭐⭐⭐⭐ Top 1% Developer on Upwork 🏆 🏆 🏆 🏆 🏆 Top 2023 AI Company 1️⃣8️⃣ Years of Experience | Looking for a dedicated, reliable team or a powerhouse developer? Your quest ends here! Welcome to my profile🚀 ⭐Top Rated Plus Upwork Contractor ⭐Spearheading one of the Top AI Companies on Upwork ⭐Partnered with over 50 Upwork clients, successfully executing more than 50 high-quality projects. Leveraging 18 years of experience in web development and 8 years in team leadership, I specialize in crafting seamless, performant interfaces and websites that drive tangible results. Skills I bring to the table🧩: • Mastery in ReactJS, Redux, GraphQL, NextJS, GatsbyJS, VueJS. • Expertise in JavaScript (ES6-ES8), TypeScript. • Proficient in Redux, Redux-Saga. • Experienced in NodeJS, Express, NestJS, NextJS. • Database knowledge: MongoDB, PostgreSQL, MySQL. • Skilled in Scss, Sass, PostCSS, HTML5, CSS3. • Building maintainable design systems with Storybook. • Client-side performance including AMP and PWA apps. • Expertise in Accessibility, 508 Compliance, SEO Optimization. • Cross-browser/cross-platform testing. • Automation QA: Cypress, Puppeteer, Playwright, Jest, Selenium. • Proficient in tooling: Webpack, Git, NPM. Happy Clients Speak📣: "Bernardo and his team bent over backward for this project. The project management and execution were awesome. We will definitely use them again." - Occam Tech "Bernardo is the best front end developer we've worked with. Was a pleasure working with him and will plan on continuing to do so." - Novo "Bernardo has been a pleasure to work with. Will continue to utilize him in future projects when the needs arise." - Cellular Outfitter My Services Include💼: • Dedicated team or a single engineer with a project manager • End-to-end software development • Building robust Design Systems for a consistent UI experience • Automation and manual testing for a bug-free application My Agile Process✅: Understanding your requirements and creating a project roadmap. Weekly sprints, with QA for each feature implemented. Continual Deployment for instant review of changes. Regular updates to keep you in the loop! Ready to unlock the power of AI for your business with a seasoned web architect? Let's talk📞

I build great websites using HTML5, CSS3, JS, and other latest web technologies. I can help you create a landing page or implement a custom CMS or other web development, always keeping in mind what's best for your business.

Updated: August 05, 2026 $53M+ Raised by Clients | 84+ MVPs Launched | 14 Years Building SaaS Startups | 100% Job Success ✅ Co-Founder & CEO at Beyond the Wow — AI Developer & Startup MVP Studio ✅ CEO at Gearheart — Enterprise SaaS MVP Development Studio (14 Years) ✅ 2x Founder of B2B SaaS Products, 1 Exit ✅ 84+ MVP Launches for Startups & Growth-Stage Teams ✅ Built SmartSuite from Scratch — $38M Raised, 7M+ Users ✅ 2–4x Faster MVP Development Using Claude Code, Lovable, Cursor, and Replit ✅ Top-Rated on Clutch & GoodFirms I'm a 2x founder with one exit and 14 years building B2B SaaS Startups as SaaS Developer and MVP Developer. I know what it means to bet on idea, run out of runway, figure out product-market fit. That's why I work as your SaaS MVP Development partner — not vendor, but full stack developer and MVP Developer building Startup MVP. I lead Gearheart and co-founded Beyond the Wow — AI Developer and SaaS MVP Development studio. I deliver SaaS MVP Development and AI Integration in weeks as MVP Developer and SaaS Developer specialist. With 14 years in SaaS MVP Development, I've shipped 84+ SaaS MVP Development projects for 70+ clients as web developer, nextjs developer, python developer, full stack web developer, or software developer. Whether you need SaaS Developer, MVP Developer, full stack developer, or AI Developer understanding SaaS Business Development — I've done it from both sides. My web app development expertise spans startup MVP and investing app launches to enterprise SaaS MVP Development with machine learning, bubbleio, email deliverability, data science, saas marketing. OUR ENGINEERING STANDARD - SmartSuite — SaaS MVP Development from scratch by senior full stack developer: $1.2M ARR in 4 weeks, $38M raised, trusted by Capital One - Globalli — SaaS MVP Development for HR/payroll across 125+ countries, SOC2 Type II, $15M raised, 15+ modules WHAT I CAN HELP - Founder Briefing: as AI Developer and SaaS developer I define ICP, confirm Startup MVP with software product manager strategy - Discovery & Prototype: clickable Startup MVP in 5 days by MVP Developer and full stack developer using Lovable, Replit, bubbleio - Rescue Diagnosis: production issues? Senior SaaS Developer, MVP Developer, full stack developer review and fix fast - SaaS MVP Development: full-cycle in 3–4 weeks — 2–4x faster. MVP Developer and full stack web developer includes AI Integration, machine learning, auth, deployment - Sprint Subscription: ongoing SaaS MVP Development support as SaaS Developer, MVP Developer partner with data scientist expertise MVP SPEED — SaaS MVP DEVELOPMENT RESULTS - Legal SaaS platform + AI chatbot (SaaS Developer) → ~2 months - AI Receptionist with CRM AI Integration (Startup MVP, machine learning) → weeks - B2B Dental Referral Startup MVP (MVP Developer) → 3 weeks - Early-stage Startup MVP prototype (MVP Developer specialty) → 5 days - Medical device SaaS MVP Development (full stack developer) → 2 weeks WHY WORK WITH ME FOR SaaS MVP DEVELOPMENT - Been There as Founder: Built and exited SaaS products. My SaaS MVP Development process and MVP Developer experience built on founder experience - Product Before Code: I ask """"should you build this?"""" before """"how?"""" My SaaS MVP Development approach starts with strategy - AI Speed, No Shortcuts: as SaaS Developer, MVP Developer, full stack developer, AI Developer, I use Claude Code, Lovable, Cursor — 2–4x faster SaaS MVP Development - Offshore Pricing, Enterprise Standard: Ukraine-based SaaS Developer, MVP Developer delivering SaaS MVP Development at 14-year standard I work as SaaS MVP Development specialist: nextjs developer, web developer, python developer, software developer, senior full stack developer, data scientist, software product manager, full stack web developer, web app development, saas marketing, machine learning, bubbleio, email deliverability expertise, nextjs developer. WHAT CLIENTS SAY """"They were my choice the moment I met them. Their commitment to solving customer problems and creating best SaaS product is unmatched."""" — Jon Darbyshire, CEO at SmartSuite """"Not only their great skills, but accountability and ownership. Feels like internal team, not vendor."""" — Febriani, AVP Product at Bababos TECH STACK FOR SaaS MVP DEVELOPMENT AI & Integration: Claude Code, OpenAI, FastAPI, machine learning, data science Frontend: React, TypeScript, Next.js, Vue.js, bubbleio Backend: FastAPI, Django, Python, Node.js, GraphQL DevOps: AWS, DigitalOcean, Kubernetes, Docker From Startup MVP and investing app builds to full SaaS MVP Development with email deliverability, I cover sales-ready products end to end as MVP Developer, SaaS Developer, and full stack developer. I am your SaaS MVP Development studio.