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I build production dashboards and AI-powered SaaS - dashboards, telegram mini apps, RAG memory systems, multi-LLM apps, and real-time voice agents - on a Next.js / React / TypeScript stack. Full-Stack Developer, 5+ 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 • 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 • AI / LLM: RAG and vector search, real-time audio agents, persistent memory, multi-provider orchestration (Claude, OpenAI), LangChain, Vercel AI SDK 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.

Are you looking for a developer who can turn your web application ideas into reality? With 6+ years of hands-on experience, I specialize in building high-quality frontend solutions, focusing on React, TypeScript, and GraphQL. I have successfully collaborated on various international projects in diverse sectors like fintech, social media, and securities. My core strength lies in translating Figma-based designs into functional and efficient React components, always ensuring that the user experience is seamless and visually accurate. What I can do for you: Develop scalable and maintainable web applications using React and TypeScript. Implement RESTful and GraphQL APIs to optimize data fetching and state management. Create reusable design components with Storybook, ensuring a consistent UI/UX. Perform unit testing with Jest to guarantee robust and bug-free code. I’m committed to delivering high-quality work and constantly staying updated with the latest trends and technologies. If you need a reliable developer who pays attention to detail and can adapt to different working styles (full-time, contract, or B2B), let's connect!

I build and maintain production web applications. I'm a full-stack developer with a strong frontend focus (Next.js / React) and solid backend foundations. I work comfortably across the entire stack: authentication, databases, file storage, real-time updates, background jobs, deployments, and long-term maintenance. Recently, I've built and shipped: - A document management system for a construction company using Next.js, Supabase (Auth, Storage, Realtime), PostgreSQL, Edge Functions, cron jobs, and Dockerized infrastructure - Multiple live business websites delivered end-to-end as a sole developer (design integration, frontend, backend, deployment, and ongoing support) I'm used to working with: - Real data, not mockups - Edge cases, permissions, loading states, and failures - Existing codebases that need improvement, not rewrites 🛠 What I'm especially good at - Turning designs into robust, usable UIs - Building clean, maintainable full-stack architectures - Authentication flows, roles, and permissions - File uploads, background processing, and real-time updates - Owning features from idea → production → iteration 💻 Tech I work with daily - Next.js - React - TypeScript - JavaScript - Tailwind CSS - Supabase (Auth, Storage, Realtime, PostgreSQL, Edge Functions) - PostgreSQL - MySQL - MSSQL - Docker - REST APIs - Background in .NET Core / C# (strong backend and system design foundation) 🤝 How I work I communicate clearly, work async-friendly, and don't need hand-holding. If something in the design or requirements doesn't make sense, I'll flag it early and propose a solution. Happy to discuss your project and see if we're a good fit. 🔎 Keyword List Full-stack developer, web application development, Next.js developer, React developer, TypeScript, JavaScript, Supabase, Supabase Auth, Supabase Realtime, Supabase Storage, PostgreSQL, Postgres, database design, REST APIs, API integration, authentication, authorization, role-based access control, file upload, background jobs, cron jobs, real-time updates, Docker, containerization, production applications, SaaS development, dashboard development, admin panels, UI development, responsive design, system design, .NET Core, C#, backend development, frontend development, maintenance and support, existing codebase, long-term collaboration

I take over code someone else wrote, often generated with AI, and get it into production. Something already exists, parts of it work, and it needs finishing without breaking what runs today. Eight years as a software engineer, three of them building AI systems that real companies run their business on. Conversational assistants and AI pipelines for a top-3 insurer in Peru, the largest shopping mall in Lima, and mortgage bots for LatAm banking. I can walk you through what broke and how we fixed it. You can check most of my work yourself. citta.es is live with paying customers and books appointments against a government portal built to block bots. tarja.app runs real row-level security in production on Next.js App Router. transcribo.es turns speech into text with the model running inside your own browser, so the audio never leaves your device. reccado and eccos are open source on GitHub. What I'm good at: - Taking over something half-built and finishing it - Maintaining and extending a SaaS that already has users, without breaking it - Adding AI features that admit when they don't know instead of making something up - Making an AI feature that works in a demo survive real users - Automating things on websites that don't want to be automated - Building the whole product, front to back Stack: TypeScript, React, Next.js, Astro, Node, Bun, Python. Postgres and Supabase, Convex, Vercel. Cloudflare Workers, D1, R2, Durable Objects, Queues. Claude, OpenAI, RAG, evals, MCP. How I work: scoped fixed-price projects and ongoing work, up to 30 hours a week, consistently, over months. Native Spanish, so I can work directly with Spanish-speaking teams. Professional English, CET, async-first. Tell me what is breaking and I'll tell you what I would do about it, before you commit to anything.

Frontend developer with 8+ years of experience, specializing in Vue.js and modern JavaScript/TypeScript ecosystems. Freelancing since 2018, building web applications for clients worldwide. Proven track record of inheriting complex legacy codebases and delivering clean, maintainable Vue 3 migrations. Currently integrating AI tooling (Cursor, Claude Code) into development workflows to accelerate delivery while maintaining code quality. Working knowledge of backend technologies (Node.js, NestJS, PHP/Laravel) when full-stack support is needed. Skills Vue 3, Vue 2, Composition API, Options API, TypeScript, JavaScript, Vuetify, Pinia, Vuex, Vue Router, TanStack Query, VueUse, Vite, Webpack, npm, Git, Vitest, Unit Testing, Component Testing, UI & Data Visualization Vuetify, Material Design, Chart.js, Responsive Design, CSS, SCSS/Sass, Ionic (Mobile Development), Auth0, OAuth, REST APIs, Axios, WebSockets, Stripe, Node.js, Express, NestJS, PHP, Laravel, MongoDB, MySQL, Cursor, Claude Code, AI assisted development, AI workflows. Speak spanish and english. Flexible schedule.

👋 I help small businesses scale by building bespoke ERP software to automate their processes. If your business has been growing and you're running it on sheets or email, chances are it has become increasingly complex to keep track of everything. Your inventory, transactions, orders, appointments... everything is done manually and you have no way to keep track of who did what when and why. This is the problem that I solve. The first common step is to look for an existing solution. This is the first thing I recommend my clients. But if you have been looking for an existing solution or have been trying one out for some time and you find that still nothing fulfills your specific needs, I want to help you. I will build an application for your business that automates all of your internal workflows. You'll be able to manage it all and give your staff different permissions to decide what data they get to see and what data they get to modify. You'll be able to keep track of actions taken by your staff, assign tasks to them, send notifications, alerts, automated emails and more. I will also create integrations with any existing services you may be already using. Perhaps all of your data is stored and created by a third-party service you're paying for, like an accounting or booking service. These type of services usually allow developers to create integrations and pull all of this data and display it or process it from your application. When you hire me, the first step is the exploration phase, where I will talk with you or someone in your team to get to understand your current situation, your needs, and help you craft a plan that helps you understand how much this project will cost you and when you'll have it ready. Usually, for this type of project, you can expect anywhere from four to ten months of engagement plus a maintenance phase afterwards. The core technologies I work with are Next.js, Nest.js, TypeScript, and SQL. Around that stack, I work with a wide range of different cloud services, libraries, ORM, and third-party API's and tools. Too many to list, feel free to ask. Let me help you scale, let's chat! 🙂