Hire the Best Nest Developers

Hello, my name is Lucas Schimidt. I am a full stack developer with knowledge in Python, SQL database language, and web technologies! With over 6 years of experience I have specialized in creating customized solutions, including web development, web design and automation. Passionate about technology!

I've built production systems serving 100,000+ users and currently lead engineering as CTO of a SaaS platform — so I bring senior-level architecture, not just code. Need a backend or full-stack engineer who ships fast without breaking what already works? I build production NestJS/Node.js APIs, Next.js web apps, and tricky third-party integrations (Stripe, GoHighLevel, Phorest, Zapier, PayFast) that other developers got stuck on. Hi 👋 I'm Rafique — a Top Rated AI-Native Full Stack Engineer with 100% Job Success on Upwork. I have 5+ years of experience building backend services, REST APIs, and SaaS platforms for startups and growing teams. Most of my work falls into one of three buckets: shipping new MVPs quickly, fixing and scaling existing apps, or building the integration layer that connects your product to the tools your business actually runs on. My core stack: 🔧 Backend: Node.js, NestJS, TypeScript, REST APIs, PostgreSQL, MongoDB, Prisma 🎨 Frontend: Next.js, React, TypeScript ☁️ Infra & Tools: AWS (Lambda, Cognito), Vercel, GitHub 🧠 AI-Native Workflow: Claude, Codex, and Cursor — used where they reduce bugs and ship faster, not as a replacement for clean architecture What clients hire me for: ✅ NestJS + Node.js backends with secure authentication and clean REST APIs ✅ Stripe, GoHighLevel, Phorest, PayFast, and Zapier integrations ✅ Next.js full-stack apps (auth, dashboards, SaaS MVPs) ✅ Performance, migrations, and stabilizing existing codebases ✅ Clear estimates, proactive updates, no surprises Recent client feedback: ⭐ "Rafique ROCKS — something I was trying to do on my own for hours and hours, he just did it." — Phorest → GoHighLevel integration ⭐ "Best developer to work with — extremely technical, patient, good communication, and most importantly knows his code. Definitely gonna hire again." — PayFast / Next.js integration ⭐ "He delivered high-quality authentication features, communicated clearly, and was very patient and professional." — NextJS + NestJS auth setup Send me a short message about what you're building or what's broken. I'll reply within 4 hours with a clear plan, realistic timeline, and an honest answer on whether I'm the right fit — no fluff, no sales pitch.

🚀 Software Architect | Technical Lead | NestJS & Node.js Expert | SaaS & Enterprise Solutions With 14+ years of experience building and scaling SaaS platforms, enterprise applications, mobile solutions, and cloud-native systems, I help startups and businesses turn complex ideas into reliable, scalable products. I specialize in designing backend architectures, leading engineering teams, and delivering high-performance applications that support real business growth. Over the years, I have: ✅ Led engineering teams of up to 15 developers ✅ Built platforms serving 20,000+ active users ✅ Designed systems processing 100,000+ API requests per day ✅ Maintained 99.9% uptime for production applications ✅ Reduced API response times from 50+ seconds to under 500 milliseconds ✅ Delivered enterprise software projects exceeding $500,000 in value My expertise spans SaaS, EdTech, Healthcare, IoT, E-commerce, Social Networking, and Enterprise Software. 💡 Core Expertise • Software Architecture & System Design • NestJS & Node.js Development • TypeScript & JavaScript • Microservices Architecture • REST API Development • MongoDB & PostgreSQL • Angular Applications • React Native Mobile Apps • AWS & Google Cloud Platform • Performance Optimization • Technical Leadership & Team Scaling • Shopify Integrations • Payment Gateway Integrations • CI/CD & Cloud Deployments 🔥 Services I Offer ✔ SaaS Product Development ✔ Backend Architecture & Development ✔ NestJS Application Development ✔ API Design & Integration ✔ Microservices Architecture ✔ Database Design & Optimization ✔ Cloud Infrastructure & Deployment ✔ Application Performance Optimization ✔ Technical Audits & Architecture Reviews ✔ Team Leadership & CTO-Level Consulting Why Clients Hire Me I don't just write code, I solve business problems. Whether you're launching an MVP, scaling an existing platform, modernizing legacy systems, or building a complex enterprise solution, I bring a combination of architecture expertise, hands-on development experience, and technical leadership that helps projects succeed. I focus on: • Clean, maintainable code • Scalable architecture • Reliable delivery • Clear communication • Long-term business value If you're looking for a senior engineer who can architect, build, optimize, and lead, let's discuss your project. Let's build something exceptional.

👨‍💻 13 years of experience · 100% Job Success · Top Rated 🏆 I work with founders and teams building software products — including apps built with AI tools like Lovable, Bolt, v0, and Cursor — who need a senior engineer who can keep up, take ownership, and make things production-ready. I've worked with clients in two ways: as a hands-on developer who ships features and handles deployments end-to-end (including Linux/VPS server setup and CI/CD), and as a technical partner who helps non-technical founders make better architectural decisions along the way. What I typically work on: ⚙️ Extending and deploying AI-generated apps ⚙️ Multi-tenant architecture, auth systems, RLS, and backend security ⚙️ AI-powered product development (Claude API, OpenAI, RAG pipelines) ⚙️ Full-stack feature development — frontend through server deployment ⚙️ Coaching founders and developers on architecture and best practices Before freelancing I co-founded Weecode — a B2B SaaS company where I led a team of 5–10 engineers building workflow automation software for large Brazilian healthcare enterprises. Let's collaborate to bring your ideas to life with innovative and reliable software solutions.

Hello! I'm a Full Stack Developer specializing in AI integration and LLM-powered applications. With 4+ years of experience delivering solutions across startups and enterprise projects, I enjoy working on problems where good engineering actually changes how a business operates. I'm particularly drawn to AI systems where the technical challenge and the real-world impact meet in the same place. 𝐀𝐈 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧 & 𝐀𝐠𝐞𝐧𝐭𝐢𝐜 𝐒𝐲𝐬𝐭𝐞𝐦𝐬 I build production-ready AI features directly into your application. From RAG pipelines and vector search using Pinecone, ChromaDB, and FAISS, to autonomous multi-agent systems using LangChain and CrewAI, I integrate it all cleanly into your existing stack. I've built document Q&A systems that cut down manual research time significantly, deployed AI chatbots for SaaS platforms, and designed automated workflow agents for operational teams. If you're in SaaS, fintech, or developer tooling, there's a good chance I've worked on something close to your problem. 𝐋𝐋𝐌 𝐄𝐯𝐚𝐥𝐮𝐚𝐭𝐢𝐨𝐧, 𝐏𝐫𝐨𝐦𝐩𝐭 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫𝐢𝐧𝐠 & 𝐅𝐢𝐧𝐞-𝐓𝐮𝐧𝐢𝐧𝐠 𝐃𝐚𝐭𝐚 I have hands-on experience designing LLM evaluation frameworks, building benchmark task suites, and collecting high-quality SFT data across real model evaluation projects. I also do prompt engineering across multi-turn, few-shot, and RAG-based contexts using the OpenAI API, Claude API, and open-source models. I understand what actually makes a model perform reliably in production, not just on paper. 𝐍𝐨𝐝𝐞.𝐣𝐬 / 𝐍𝐞𝐬𝐭𝐉𝐒 / 𝐄𝐱𝐩𝐫𝐞𝐬𝐬.𝐣𝐬 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 I specialize in building scalable backend systems using Node.js, Express, and NestJS. REST APIs, microservices, real-time WebSocket systems, and AI-ready backend architecture are all in my wheelhouse. I work comfortably with PostgreSQL, MySQL, and MongoDB, and I keep performance and clean architecture at the center of everything I build. 𝐑𝐞𝐚𝐜𝐭.𝐣𝐬 & 𝐍𝐞𝐱𝐭.𝐣𝐬 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 I build dynamic, responsive, and SEO-optimized frontends using React.js and Next.js, including streaming LLM interfaces and AI-powered chat UIs. From interactive SPAs to high-performance SSR apps, I make sure your frontend is fast, scalable, and easy to maintain. 𝐀𝐧𝐠𝐮𝐥𝐚𝐫 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 For larger, structured frontend projects I use Angular with TypeScript, modular design, and reactive programming. I've built dashboards, data-driven interfaces, and enterprise-grade systems where long-term maintainability really matters. 𝐀𝐒𝐏.𝐍𝐄𝐓 𝐂𝐨𝐫𝐞 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 I also work with ASP.NET Core for businesses on Microsoft stacks or with enterprise-level requirements. Whether it's secure APIs or full-featured web apps, I deliver .NET solutions that hold up in production. 𝐖𝐡𝐲 𝐖𝐨𝐫𝐤 𝐖𝐢𝐭𝐡 𝐌𝐞? 𝐀𝐈 + 𝐅𝐮𝐥𝐥-𝐒𝐭𝐚𝐜𝐤 𝐢𝐧 𝐎𝐧𝐞: Most developers can build an app or bolt on a chatbot. I do both in one coherent system, so you don't end up with two contractors pointing fingers at each other. 𝐏𝐫𝐨𝐝𝐮𝐜𝐭𝐢𝐨𝐧-𝐅𝐢𝐫𝐬𝐭 𝐌𝐢𝐧𝐝𝐬𝐞𝐭: I follow best practices for performance, security, and maintainability across every project I take on. 𝐑𝐞𝐚𝐥 𝐏𝐫𝐨𝐛𝐥𝐞𝐦 𝐒𝐨𝐥𝐯𝐞𝐫: I think through the actual business problem first and engineer a solution that fits, not just code that runs. 𝐅𝐨𝐜𝐮𝐬𝐞𝐝 𝐄𝐧𝐠𝐚𝐠𝐞𝐦𝐞𝐧𝐭: I take on a small number of projects at a time so each one gets real attention, not a copy-paste solution. 𝐓𝐫𝐚𝐧𝐬𝐩𝐚𝐫𝐞𝐧𝐭 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧: I keep you in the loop at every stage and work closely with you to make sure your vision gets executed the right way. Send me a message describing your project and I'll get back to you within 24 hours with a clear view of how I can help and what it would take to get it done.

I build production dashboards and AI-powered SaaS - RAG memory systems, multi-LLM apps, and real-time voice agents - on a Next.js / React / TypeScript stack. Full-Stack Developer, 4+ years building scalable, secure web apps across AI, healthcare, web3, and IoT - from PostgreSQL schema and payments to streaming LLM features and pixel-perfect UI. Teams also bring me in to debug, harden, and fix vulnerabilities in live products. WHAT I DO BEST • AI / LLM: RAG and vector search, real-time audio agents, persistent memory, multi-provider orchestration (Claude, OpenAI), LangChain, Vercel AI SDK • Full-stack SaaS: multi-tenant dashboards, role-based access, admin panels, drag-and-drop UIs, PDF and media handling • Payments & security: Stripe and other gateways (one-time + subscriptions), webhook-verified flows, security audits and vulnerability fixes • Web3: wallet connections, smart-contract interactions, NFT / quest platforms SELECTED PROJECTS • AI Coaching Platform - production AI SaaS with real-time audio agents, a RAG memory system (vector DB + Postgres) grounding every response in user history, multi-provider LLM streaming, and automated workflows. (Next.js, Express, Supabase, Vercel AI SDK, LangChain) • Healthcare Dashboard - role-based patient and doctor portals with task management (kanban, drag-and-drop), calendar, AI doctor tools, and PDF/DOCX handling. • NFT Quest Platform (web3) - wallet and smart-contract interactions; full flow from admin quest creation to the user experience; migrated Vue/Nuxt to Next.js. • Prize Competition Platform - secure card payments (webhook verification, settlement tracking), instant-win mechanics, and admin payouts; found and fixed a payment vulnerability in a security audit. • Analytics Dashboards - complex data builder with dynamic visualizations and secure profile management. • SaaS for Artists - auth, group collaboration, media handling (text and audio), audio players, and calendar. TECH STACK Frontend: React, Next.js (App Router, SSR), TypeScript, Tailwind, shadcn/ui, Framer Motion, Redux Toolkit, TanStack Query Backend: Node.js, Express, Nest.js, serverless (Firebase / Supabase functions), REST APIs, webhooks, cron jobs AI / LLM: Claude, OpenAI, Vercel AI SDK, LangChain, RAG, vector databases Data & Auth: PostgreSQL, Supabase, MongoDB, Firebase; NextAuth, Firebase Auth, JWT, OTP Payments: Stripe + other gateways (one-time + subscriptions) Tools: GitHub / GitLab, Figma, Vercel, Sentry HOW I WORK Clean, maintainable code. Honest timelines and clear communication. I care about what bites later - security, edge cases, and performance.