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𝐇𝐢, 𝐭𝐡𝐞𝐫𝐞! 🖖 Looking for an expert Full Stack Developer? Look no further! ✨ My name is André, I'm a skilled Full Stack Developer with 9+ years of experience in the field, and I will take your project across the finish line. ✌ I've successfully developed a full range of software, from enterprise systems to SaaS products or mobile apps. I will provide high-quality frontend, backend, API, and DB solutions, with clean, bug-free, well-tested code. 🤝 I specialize in the 𝑀𝐸𝑅𝑁 stack: ✅ 𝑁ode.js/𝐸xpress.js ✅ 𝑅eact ✅ 𝑀ongoDB ✅ JavaScript/Typescript I'm experienced with different stacks and I'm always eager to learn something new. Test me! 𝐋𝐞𝐭'𝐬 𝐦𝐚𝐤𝐞 𝐲𝐨𝐮𝐫 𝐩𝐫𝐨𝐣𝐞𝐜𝐭 𝐚 𝐫𝐞𝐚𝐥𝐢𝐭𝐲! 🚀

Startups, enterprises and public-sector organizations bring me in when the product needs strong technical decisions, not just execution - production AI systems, SaaS platforms and fintech, from architecture to live deployment. Most engagements start with a fixed-price design phase that defines architecture, scope and roadmap, then convert into fixed milestones, so delivery stays structured and budget predictable. Rate $125-150/hr depending on complexity; most work is delivered as fixed-price milestones. What I specialise in: AI/LLM systems - RAG pipelines, multi-tenant AI assistants, agent orchestration, Claude/OpenAI integrations, structured outputs, eval pipelines. SaaS platforms - multi-tenant architecture, subscription billing, RBAC, admin backends, scalable APIs across web and mobile. Fintech/compliance - ACH, Stripe Connect, idempotent payment webhooks, audit logging, GDPR-compliant data. Govtech/regulated - transparency platforms, donor-funded compliance, multi-language reporting. Blockchain/Web3 - Solana smart contracts, SPL tokens, DeFi integrations. Selected results (live demos and links in the Portfolio section): Minerva (active production) - multi-tenant AI assistant platform architected end to end: organizations upload document libraries and deploy embeddable chatbots on their own knowledge base. Hybrid retrieval (BM25 + dense vector + semantic), Entra ID + RBAC + MFA, full tenant isolation, golden-query eval harness in CI. NestJS, Next.js, Azure OpenAI. Diginak.ai (active production, lead architect) - logistics document automation that auto-processes ~78% of inbound PDF/CSV/Excel with zero human touch; the remainder routes to human review with confidence scores. Claude API + tool use, state-machine workflow engine, retry/idempotency, 850+ automated tests. NestJS, PostgreSQL. Walletta AI Cashier (concluded May 2026, 5-star) - real-time voice agent with sub-500ms perceived latency. Claude + GPT-4o orchestration, structured tool calls with confidence-scored routing, persistent WebSocket, retry with circuit breaker. LiveKit, Deepgram, ElevenLabs, NestJS. Damen Capital Portal (concluded May 2026, 5-star) - loan-servicing portal for a private lender with the full ACH lifecycle: tokenization, NACHA returns R01-R85, HMAC-verified idempotent webhooks, append-only audit log, OAuth 2.0 + RBAC, scheduled reconciliation. NestJS + Fastify, Supabase. PulseYourBiz (active production) - all-in-one SaaS for service providers: bookings, payments, invoicing, CRM, analytics. Five-app Turborepo monorepo, Stripe Connect payouts, idempotent webhooks, React Native mobile. Docker + GitHub Actions. ProveYourImpact (production) - multi-tenant governance/compliance platform for donor-funded projects in PALOP countries: 20 API modules, 9-role RBAC, configurable workflow engine, audit log, EU/UNDP/World Bank report generators in four languages. NestJS, Next.js, PostgreSQL + RLS. Also shipped: no-code Solana token/DeFi platform with 1,500+ users (SwapForge), offline-first clinical decision support for underserved regions (ExtendYourClinic), multi-tenant VetSaaS with PostgreSQL RLS isolation (acti.vet), React Native apps live on both app stores (ForroAI). Tech stack: Backend: Node.js, NestJS, Python, FastAPI, REST, GraphQL. Frontend: React, Next.js, React Native, Expo, TypeScript, Tailwind. AI: Claude, OpenAI, RAG, pgvector, Azure Cognitive Search, structured outputs (Zod/Pydantic), prompt caching, tool use, eval harnesses in CI. Cloud: Azure (Functions, OpenAI, Entra ID, Key Vault, App Insights, Bicep IaC), AWS, GCP, Docker, GitHub Actions. Databases: PostgreSQL, MongoDB, Redis, Supabase, RLS tenant isolation. Blockchain: Solana, Anchor, SPL, Jupiter, Solidity, EVM. Working model: 25-30 hrs/week across a small number of parallel engagements. Best fit when the product needs architectural ownership - not a fit for quick fixes or one-off tasks.

🚀 Is your MVP taking months instead of weeks? 💡 Tired of hiring a Front End Developer who doesn't understand your business and just writes code? I'm a Front End Developer helping startup founders launch production-ready MVPs in 𝟮–𝟯 𝘄𝗲𝗲𝗸𝘀, using a clear, 𝗯𝘂𝘀𝗶𝗻𝗲𝘀𝘀-𝗼𝗿𝗶𝗲𝗻𝘁𝗲𝗱 development approach. As an Upwork Expert-Vetted React Front End Developer with a Master's in Computer Science and 7+ years of experience building scalable SaaS platforms, dashboards, and custom APIs, I translate complex tech into clear product decisions that drive results. Over those years as a Front End Developer I've worked with startups from idea stage to Series B, as well as enterprise clients like 𝗦𝗮𝗺𝘀𝘂𝗻𝗴, 𝗛𝗼𝗿𝗶𝘇𝗼𝗻𝘀, and 𝗕𝗲𝗻𝘁𝗹𝗲𝘆 - always focusing on fast delivery, clean architecture, and measurable outcomes. 💬 Here's what founders say after working with me as their Front End Developer: "𝘎𝘳𝘦𝘢𝘵 𝘦𝘹𝘱𝘦𝘳𝘪𝘦𝘯𝘤𝘦 𝘸𝘰𝘳𝘬𝘪𝘯𝘨 𝘸𝘪𝘵𝘩 𝘒𝘺𝘳𝘺𝘭𝘰! 𝘏𝘦 𝘥𝘦𝘭𝘪𝘷𝘦𝘳𝘦𝘥 𝘢 𝘩𝘪𝘨𝘩-𝘲𝘶𝘢𝘭𝘪𝘵𝘺 𝘙𝘦𝘢𝘤𝘵 + 𝘛𝘺𝘱𝘦𝘚𝘤𝘳𝘪𝘱𝘵 𝘧𝘳𝘰𝘯𝘵𝘦𝘯𝘥 𝘴𝘵𝘺𝘭𝘦𝘥 𝘸𝘪𝘵𝘩 𝘛𝘢𝘪𝘭𝘸𝘪𝘯𝘥 𝘊𝘚𝘚, 𝘣𝘶𝘪𝘭𝘵 𝘸𝘪𝘵𝘩 𝘤𝘭𝘦𝘢𝘯 𝘤𝘰𝘥𝘦 𝘢𝘯𝘥 𝘴𝘵𝘳𝘰𝘯𝘨 𝘢𝘵𝘵𝘦𝘯𝘵𝘪𝘰𝘯 𝘵𝘰 𝘥𝘦𝘵𝘢𝘪𝘭. 𝘊𝘰𝘮𝘮𝘶𝘯𝘪𝘤𝘢𝘵𝘪𝘰𝘯 𝘸𝘢𝘴 𝘴𝘮𝘰𝘰𝘵𝘩 𝘢𝘯𝘥 𝘥𝘦𝘭𝘪𝘷𝘦𝘳𝘺 𝘰𝘯 𝘵𝘪𝘮𝘦 - 𝘩𝘪𝘨𝘩𝘭𝘺 𝘳𝘦𝘤𝘰𝘮𝘮𝘦𝘯𝘥!" "𝘒𝘺𝘳𝘺𝘭𝘰 𝘥𝘦𝘭𝘪𝘷𝘦𝘳𝘦𝘥 𝘤𝘭𝘦𝘢𝘯, 𝘴𝘤𝘢𝘭𝘢𝘣𝘭𝘦 𝘤𝘰𝘥𝘦 𝘢𝘯𝘥 𝘩𝘢𝘯𝘥𝘭𝘦𝘥 𝘧𝘳𝘰𝘯𝘵-𝘦𝘯𝘥 𝘥𝘦𝘷𝘦𝘭𝘰𝘱𝘮𝘦𝘯𝘵 𝘸𝘪𝘵𝘩 𝘱𝘳𝘦𝘤𝘪𝘴𝘪𝘰𝘯. 𝘊𝘰𝘮𝘮𝘶𝘯𝘪𝘤𝘢𝘵𝘪𝘰𝘯 𝘸𝘢𝘴 𝘴𝘮𝘰𝘰𝘵𝘩, 𝘢𝘯𝘥 𝘩𝘦 𝘸𝘢𝘴 𝘱𝘳𝘰𝘢𝘤𝘵𝘪𝘷𝘦 𝘪𝘯 𝘴𝘰𝘭𝘷𝘪𝘯𝘨 𝘵𝘦𝘤𝘩𝘯𝘪𝘤𝘢𝘭 𝘤𝘩𝘢𝘭𝘭𝘦𝘯𝘨𝘦𝘴. 𝘏𝘪𝘨𝘩𝘭𝘺 𝘳𝘦𝘤𝘰𝘮𝘮𝘦𝘯𝘥𝘦𝘥 𝘧𝘰𝘳 𝘸𝘦𝘣 𝘥𝘦𝘷𝘦𝘭𝘰𝘱𝘮𝘦𝘯𝘵, 𝘈𝘗𝘐 𝘪𝘯𝘵𝘦𝘨𝘳𝘢𝘵𝘪𝘰𝘯, 𝘢𝘯𝘥 𝘱𝘦𝘳𝘧𝘰𝘳𝘮𝘢𝘯𝘤𝘦-𝘧𝘰𝘤𝘶𝘴𝘦𝘥 𝘦𝘯𝘨𝘪𝘯𝘦𝘦𝘳𝘪𝘯𝘨 𝘱𝘳𝘰𝘫𝘦𝘤𝘵𝘴." "𝘏𝘢𝘱𝘱𝘺 𝘸𝘪𝘵𝘩 𝘴𝘱𝘦𝘦𝘥 𝘢𝘯𝘥 𝘲𝘶𝘢𝘭𝘪𝘵𝘺!" Why founders keep me as their long-term Front End Developer: 🎯 Business-first mindset - a Front End Developer who understands your priorities and aligns tech decisions with them ⚙️ Rapid MVP execution - from concept to launch in weeks, not months 🧩 Front End ownership - a senior Front End Developer handling React, Next.js, API integrations, Tailwind, MUI and scalable architectures 🧩 Full Stack ownership - MERN, Express.js, Node.js, MongoDB 🧠 Strategic guidance - more than a Front End Developer: I help you define what truly matters for your first release 📌 Typical projects I take on as a Front End Developer: SaaS dashboards and admin panels - React Front End Developer work with complex state and data-heavy UI MVPs from Figma to production - a Front End Developer who ships, not just prototypes Custom API integrations and internal tools for growing teams Frontend rescue - stepping in as the new Front End Developer on an existing codebase I don't take on last-minute fixes or e-commerce stores - as a Front End Developer I focus on SaaS and MVP projects where clear product thinking makes the difference. If you're a founder looking for a reliable Front End Developer who speaks your language and delivers predictably - let's build something great together. 🛠️ Tech Stack & Tools: Languages & Libraries: React, React.js, Node.js, JavaScript, ReactJS TypeScript, ReactJS NodeJS, Python, PHP, React Native, NextJS, MERN Stack Styling: Material UI, Tailwind CSS, MUI React, custom SCSS / CSS Build Tools: Webpack, Vite, NPM UI/UX: Figma, Frontend Design tools for pixel-perfect visuals Visualization: Leaflet, maps & data-driven charts Databases: MongoDB, PostgreSQL, MySQL, Firebase State Management: Redux, Zustand, RTK Query Cross-browser / cross-platform manual testing

Hello, FullStack .NetCore/React Developer, looking to help you at building scalable and maintainable app. Background in Electronic Engineering but have been working in FullStack for about 3 years. I have good knowledge of the React ecosystem and most relevant libraries, to build an app from the ground up. Right now trying to focus on providing UI to replace business oriented problems, bringing things like interactive tables and data visualisation to replace excel workflows. Some of my experiences and knowledge: - Javascript/Typescript - ReactQuery, Zustand, Redux-Toolkit... - Css, Tailwind, clsx... - ReactHook-Form, Formik, Zod... -Nextjs -Any Rest API integration, Axios/Fetch, Odata. In my portfolio I have a complete diagram with all technologies we have worked on.

Hey! I have 7 years of experience working as backend/fullstack software developer mainly focusing on Java-ReactJS apps. I worked with manufacturing systems (SAP), high load systems (Amazon), automations and health care. If you need someone who is attentive to details and knows what data protection is - text me!

💼 8+ years of Full Stack Development experience with strong expertise in Software Architecture 🌍 120+ projects delivered for clients in the US, Canada, Europe & Asia 💰 20M+ in client revenue generated through high-performance web apps 🚀 40+ SaaS platforms & 12 HR solutions successfully launched 📱 Dozens of responsive Progressive Web Apps (PWA) delivered ⭐ 5-Star ratings across all projects I lead a team specializing in web development, mobile development, and SaaS development, with deep hands-on experience building scalable, high-performance products for startups and growing businesses. Our team includes dedicated frontend developers in React, backend developers in Node.js, and UI/UX designers - together we take full ownership of the product lifecycle, from idea validation and MVP delivery to stable production releases. 🚀 MVP & Startup Product Development We help founders move fast without sacrificing quality through agile web development and mobile development workflows. Our focus is on: Turning ideas into working MVPs Building investor-ready demos Launching beta products quickly Our team delivers: Rapid MVP development (UI/UX design - Frontend - Backend) UX flows and prototyping in Figma Production-ready code with React, Node.js, React Native, and Swift Secure third-party integrations (Stripe, Firebase, Auth0, Twilio, Google Maps) Clean, scalable architecture designed for long-term growth and SaaS development 💻 Web Development Our React frontend development team and backend developers work together on Node.js to build modern web applications that are fast, maintainable, and scalable. Front-End (Frontend developers React focus): React.js, Next.js TypeScript, JavaScript (ES6+) HTML5, CSS3, Tailwind Back-End (Backend developers/development with Node.js): Node.js, NestJS, Express.js REST & GraphQL APIs PostgreSQL, MongoDB, MySQL CMS & Headless Solutions: Sanity, Contentful, Strapi Every project combines React frontend development and Node.js backend development to support performance, scalability, and clean code practices - a foundation that's especially critical for SaaS development. 📱 Mobile App Development Our mobile development specialists create mobile applications optimized for real-world usage: React Native for fast cross-platform delivery Swift & SwiftUI for native iOS apps Firebase, push notifications, analytics App Store deployment and optimization Offline mode, multi-language support, battery efficiency Our backend developers use Node.js to handle server-side logic, ensuring smooth communication between mobile apps and backend systems. ☁️ Cloud, DevOps & System Architecture Our backend development team designs and maintains reliable, production-ready infrastructure: AWS: Lambda, EC2, S3, CloudFront, RDS Docker, Kubernetes, Terraform CI/CD pipelines (GitHub Actions, GitLab CI) Monitoring & logging (Sentry, Prometheus, Grafana) The goal: stable deployments, predictable scaling, and minimal downtime - essential for any serious SaaS development effort. 🎨 UI/UX Design & Development We work with strong UI/UX design awareness baked into every stage, not just code execution: Product discovery & user flows Design systems & UI kits Accessibility (WCAG) Responsive, conversion-focused layouts This helps ensure the product is not only functional, but usable and intuitive - whether it's a web development project, a mobile development project, or a full SaaS development build. 🤝 How We Work Direct communication with our frontend developers, React, backend developers, Node.js, and UI/UX design team (no middle layers) Transparent progress and clear estimates Agile mindset and iterative delivery Clean, documented, maintainable code Result: reliable products built by a team that understands both business goals and technical execution across web development, mobile development, and SaaS development. Just send me a message or click Invite, and I'll personally oversee your project in a Product Manager role, with our development team executing the work.