๐จAre you looking for a seasoned Full Stack Developer ๐ who can transform your vision into a high-performance digital productโLook no furtherโ๏ธWith over ๐ต ๐๐ฒ๐ฎ๐ฟ๐ ๐ผ๐ณ ๐ต๐ฎ๐ป๐ฑ๐-๐ผ๐ป ๐ฒ๐ ๐ฝ๐ฒ๐ฟ๐ถ๐ฒ๐ป๐ฐ๐ฒ ๐ I specialize in building robust ๐ฆพ scalable ๐ and intuitive web applications using the latest technologies like ๐ฅ๐ฒ๐ฎ๐ฐ๐.๐ท๐, ๐๐ป๐ด๐๐น๐ฎ๐ฟ, ๐ฎ๐ป๐ฑ ๐ก๐ผ๐ฑ๐ฒ.๐ท๐ ๐ฅ๐ฅ๐ฅ
โ ๐ช๐๐ฌ ๐ช๐ข๐ฅ๐ ๐ช๐๐ง๐ ๐ ๐?
๐ ๐๐ ๐ฝ๐ฒ๐ฟ๐๐ถ๐๐ฒ ๐๐ฐ๐ฟ๐ผ๐๐ ๐๐ต๐ฒ ๐ฆ๐๐ฎ๐ฐ๐ธ: Whether it's front-end magic with ๐ฅ๐ฒ๐ฎ๐ฐ๐.๐ท๐/๐๐ป๐ด๐๐น๐ฎ๐ฟ or back-end power with ๐ก๐ผ๐ฑ๐ฒ.๐ท๐, I've mastered the full stack. I ensure seamless integration, clean code, and efficient solutions that meet your business goals ๐
๐ ๐ง๐ฎ๐ถ๐น๐ผ๐ฟ๐ฒ๐ฑ ๐ฆ๐ผ๐น๐๐๐ถ๐ผ๐ป๐: I believe in a user-centric approach, tailoring every project to meet your unique needs. From dynamic single-page applications to complex enterprise systems, I deliver solutions that drive success ๐
๐ช ๐๐ด๐ถ๐น๐ฒ ๐ฎ๐ป๐ฑ ๐๐ผ๐น๐น๐ฎ๐ฏ๐ผ๐ฟ๐ฎ๐๐ถ๐๐ฒ: I thrive in agile environments, working closely with clients to ensure their vision is realized at every stage. Transparent communication, iterative progress, and on-time delivery are my top priorities โฑ
โ ๐ฃ๐ฒ๐ฟ๐ณ๐ผ๐ฟ๐บ๐ฎ๐ป๐ฐ๐ฒ ๐ฎ๐ป๐ฑ ๐ฆ๐ฐ๐ฎ๐น๐ฎ๐ฏ๐ถ๐น๐ถ๐๐: I build with the future in mind, ensuring your applications are not only fast and responsive but also scalable and maintainable. I'm committed to delivering quality that stands the test of time ๐โโ๏ธ
๐ ๐๐๐๐๐ถ๐ป๐ด-๐๐ฑ๐ด๐ฒ ๐ง๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐ถ๐ฒ๐: Staying updated with the latest trends and technologies is key. I constantly refine my skills to leverage the best tools and practices in the industry, including TypeScript, Express, MongoDB, AWS, and more โ๏ธ
๐ ๐ ๐ ๐๐ฒ๐ ๐ฆ๐ธ๐ถ๐น๐น๐ ๐๐ป๐ฐ๐น๐๐ฑ๐ฒ: ๐
โ ๐๐ฟ๐ผ๐ป๐-๐๐ป๐ฑ: React.js, Angular, Redux, HTML5, CSS3, SASS, Bootstrap, Material UI
โ ๐๐ฎ๐ฐ๐ธ-๐๐ป๐ฑ: Node.js, Express.js, RESTful APIs, GraphQL
โ ๐๐ฎ๐๐ฎ๐ฏ๐ฎ๐๐ฒ: MongoDB, MySQL, PostgreSQL
โ ๐๐ฒ๐๐ข๐ฝ๐: Docker, Kubernetes, CI/CD Pipelines, AWS, Azure
โ ๐ง๐ฒ๐๐๐ถ๐ป๐ด: Jest, Mocha, Chai, Cypress
๐ซ ๐๐๐๐ฅ ๐๐ช โ๐๐๐๐๐ฅ๐ค ๐๐๐ช: ๐ซ
๐ฌ "๐๐ฏ ๐ฆ๐น๐ค๐ฆ๐ฑ๐ต๐ช๐ฐ๐ฏ๐ข๐ญ ๐ฅ๐ฆ๐ท๐ฆ๐ญ๐ฐ๐ฑ๐ฆ๐ณ ๐ธ๐ฉ๐ฐ ๐ค๐ฐ๐ฏ๐ด๐ช๐ด๐ต๐ฆ๐ฏ๐ต๐ญ๐บ ๐ฅ๐ฆ๐ญ๐ช๐ท๐ฆ๐ณ๐ด ๐ฉ๐ช๐จ๐ฉ-๐ฒ๐ถ๐ข๐ญ๐ช๐ต๐บ ๐ธ๐ฐ๐ณ๐ฌ. ๐๐ช๐ด ๐ข๐ฃ๐ช๐ญ๐ช๐ต๐บ ๐ต๐ฐ ๐ฉ๐ข๐ฏ๐ฅ๐ญ๐ฆ ๐ค๐ฐ๐ฎ๐ฑ๐ญ๐ฆ๐น ๐ต๐ข๐ด๐ฌ๐ด ๐ธ๐ช๐ต๐ฉ ๐ฆ๐ข๐ด๐ฆ ๐ช๐ด ๐ช๐ฎ๐ฑ๐ณ๐ฆ๐ด๐ด๐ช๐ท๐ฆ."
๐ฌ "๐๐ง๐ง๐ช๐ค๐ช๐ฆ๐ฏ๐ต, ๐ณ๐ฆ๐ญ๐ช๐ข๐ฃ๐ญ๐ฆ, ๐ข๐ฏ๐ฅ ๐ข ๐ต๐ณ๐ถ๐ฆ ๐ฆ๐น๐ฑ๐ฆ๐ณ๐ต ๐ช๐ฏ ๐ง๐ถ๐ญ๐ญ-๐ด๐ต๐ข๐ค๐ฌ ๐ฅ๐ฆ๐ท๐ฆ๐ญ๐ฐ๐ฑ๐ฎ๐ฆ๐ฏ๐ต. ๐๐ฉ๐ฆ ๐ฑ๐ณ๐ฐ๐ซ๐ฆ๐ค๐ต ๐ฆ๐น๐ค๐ฆ๐ฆ๐ฅ๐ฆ๐ฅ ๐ฐ๐ถ๐ณ ๐ฆ๐น๐ฑ๐ฆ๐ค๐ต๐ข๐ต๐ช๐ฐ๐ฏ๐ด."
๐ ๐ฅ๐ฒ๐ฎ๐ฑ๐ ๐๐ผ ๐๐ฟ๐ถ๐ป๐ด ๐ฌ๐ผ๐๐ฟ ๐ฃ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐ ๐๐ผ ๐๐ถ๐ณ๐ฒ? ๐
Letโs collaborate to build something extraordinary! Whether you need a new web application, a feature upgrade, or technical consultation, I'm here to help. Drop me a message, and let's discuss how we can achieve your goals together ๐๐๐
KEYWORDS:
Full-stack development | fullstack developer | web development | React.js | Angular | Node.js | JavaScript | HTML5 | CSS3 | TypeScript | front-end development | frontend developer | back-end development | backend developer | MongoDB | MySQL | PostgreSQL | Express.js | RESTful APIs | GraphQL | Bootstrap | Material UI | SASS | LESS | Redux | Docker | Kubernetes | CI/CD pipelines | AWS | Azure | Firebase | Git | GitHub | Bitbucket | DevOps | Agile development | Scrum | responsive design | single-page applications | SPAs | web apps | cross-browser compatibility | performance optimization | web security | authentication | authorization | JWT | OAuth | JSON | AJAX | WebSockets | API integration | microservices | serverless architecture | cloud computing | MVC architecture | database design | NoSQL | SQL | data modeling | TDD | unit testing | integration testing | Jest | Mocha | Chai | Cypress | Selenium | continuous integration | continuous deployment | code review | code quality | design patterns | MVC | MVVM | version control | object-oriented programming | OOP | functional programming | ES6+ | npm | yarn | package management | web components | PWA | progressive web apps | mobile-first design | UI/UX design | wireframing | prototyping | REST architecture | SOAP | XML | Redux-Saga | Next.js | Nuxt.js | Angular CLI | React Router | server-side rendering | SSR | client-side rendering | CSR | SEO optimization | Webpack | Babel | Gulp | Grunt | software architecture | system design | debugging | troubleshooting | web accessibility | ADA compliance | node js developer | react js node js | node js angular | mongodb node js | backend nodejs | backend nodejs | nodejs developer | react nodejs | nodejs mongodb | typescript nodejs | node.js developer | react.js node.js | backend node.js | node.js aws | vue.js node.js | backend nodejs | react | react developer | react native | react native mobile | react typescript | beta reader | reactjs | reactjs redux | reactjs developer | reactjs typescript | react.js | react.js node.js | react.js developer
Node.js
JavaScript
Web Application
PHP
TypeScript
API
API Integration
Python
MySQL
Web Development
React
HTML
Web Design
CSS
HTML5
Anton C.
Barcelona, Spain
$35/hr
4.9
78 jobs
โญ๏ธ ๐ฆ๐ฝ๐ฒ๐ฒ๐ฑ ๐๐ถ๐๐ต๐ผ๐๐ ๐ฐ๐๐๐๐ถ๐ป๐ด ๐ฐ๐ผ๐ฟ๐ป๐ฒ๐ฟ๐: working code on time, every time
โญ๏ธ ๐๐๐ฑ๐ด๐ฒ๐ ๐ฑ๐ถ๐๐ฐ๐ถ๐ฝ๐น๐ถ๐ป๐ฒ: every billed hour is justified โ no filler tasks
โญ๏ธ ๐๐๐๐ถ๐ป๐ฒ๐๐-๐ณ๐ถ๐ฟ๐๐ ๐๐ต๐ถ๐ป๐ธ๐ถ๐ป๐ด: I understand the problem before I write code, so your budget goes into the product, not experiments
๐ React Developer, Full Stack Developer React, Frontend React Developer โ specializing in production-ready SaaS platforms, multi-tenant B2B systems, and AI-powered web applications.
โญ Top Rated Plus โข 6+ years as a React Developer โข 70+ projects delivered as a Full Stack Developer React Next.js โข 5,000+ Upwork hours as a React Native Developer โข ~70% returning clients as a Frontend React Developer
WHY HIRE ME
๐ 6+ years and ๐ฆ 70+ projects mark my work as a Full Stack Developer React Node, building SaaS Platform, MVP, and AI-Powered Web Application solutions.
๐ ~70% of clients return โ a track record built as a React Developer through partnerships lasting months to years, working as a Frontend React Developer and Full Stack React Developer.
โฑ๏ธ 5,000+ Upwork hours logged as a React.js Developer, Node.js Developer, and React Native Developer.
โญ Top Rated Plus status reflects steady delivery as a Front End Developer and Nextjs Developer, with a track record of on-time launches.
WHERE I DELIVER
Working as a Full Stack Developer React Node, I built a multi-tenant B2B SaaS platform with React, Next.js, and Node.js โ OWASP-compliant authentication, role-based access control, custom workflow logic, and full Stripe billing (Subscriptions and Connect), backed by PostgreSQL via Prisma with REST and GraphQL APIs on AWS.
Building as a React Developer with the OpenAI and Anthropic APIs, I developed an AI-powered SaaS product with React, Next.js, Node.js, and Supabase โ RAG pipelines, embeddings, semantic search, real-time streaming, Stripe Checkout billing, and an offline-ready PWA on Vercel.
My work as a Frontend React Developer covers two-sided marketplaces, e-commerce platforms, booking and scheduling systems, real-time chat, analytics dashboards, and internal tools.
Complex features like authentication flows, payment processing, real-time data, and third-party integrations fall under my Front End Developer work.
Deep App Router, Server Components, SSR, SSG, and ISR experience comes from my time as a React Next.js Developer and Node.js Developer, plus API routes and middleware.
Core Web Vitals, accessibility, and responsive, cross-browser interfaces are where my Full Stack React Developer background shows.
The same product extends to iOS and Android through my React Native Developer work with React Native and Expo.
Production-ready code from MVP to scale is what I deliver as a Web App Developer React and React App Developer.
REST and GraphQL APIs, authentication flows, and background jobs for high-traffic products come out of my Node js Developer and Full Stack Developer React Node experience.
SEO-friendly, fast-loading storefronts and marketing sites come from my React Web Developer and Nextjs Developer work.
TECH STACK
On the frontend, I build with React, Next.js, and TypeScript, styling with Tailwind CSS and Shadcn/ui and handling state with Redux or Zustand โ whatever keeps the codebase easy to hand off. The backend runs on Node.js, usually via Express or NestJS, talking to PostgreSQL through Prisma, or to Supabase and Firebase when a project needs managed auth and real-time out of the box, exposed through REST or GraphQL APIs. I deploy to AWS or Vercel with GitHub Actions running CI/CD, so every push ships cleanly. When a project calls for OAuth, webhooks, transactional email via SendGrid, or automation through Zapier, that comes built into the stack, not bolted on later.
MIXED-STACK SUPPORT
Python, PHP, Laravel, MySQL, MongoDB, Redis, WordPress, Java, FastAPI, jQuery, and Web3 round out a broader Python Developer, Wordpress Developer, and React Web Developer skill set โ and as a Mobile App Developer, I pick up inherited code and mixed stacks quickly.
INDUSTRIES
SaaS & B2B, AI Startups, Marketplaces & E-commerce, Fintech, Healthtech, Ed-tech, and Real estate โ where my React Developer and Full Stack Developer React Node work has landed.
WHAT CLIENTS HIRE ME FOR
Scalable web applications, secure REST and GraphQL APIs, high-performance Next.js front-ends, and reliable, production-ready SaaS โ that's what clients bring me on for as a React Developer, Full Stack Developer React Node, and Frontend React Developer, backed by ๐ฆ 70+ projects, ๐ 6+ years, and ๐ ~70% returning clients.
Building, scaling, or improving a product? I work as a React Developer, Full Stack Developer React Node, Frontend React Developer, React Native Developer, and Nextjs Developer โ let's talk on a quick call. ๐
Node.js
JavaScript
jQuery
MongoDB
React
CSS
Front-End Development
TypeScript
Bootstrap
HTML
PHP
React Native
Vue.js
Web Design
Responsive Design
Redux
CSS 3
Python
WordPress
HTML5
Maria S.
Roses, Spain
$75/hr
5.0
2 jobs
I build SaaS products that work well and look great, and I've been doing it for 6 years.
I build complete products โ backend, frontend, and everything in between โ for medium-sized businesses that need software that works reliably and looks professional. SaaS platforms, subscription billing, role-based systems, real-time features, clean dashboards.
I combine technical execution with design sensibility: the apps I build don't just function well, they feel right to use.
End-to-end ownership, tight deadlines, quality results. Let's build something.
Node.js
ExpressJS
JavaScript
Web Application
Angular
HTML
CSS
SCSS
C#
Java
Bootstrap
Web Development
Responsive Design
Stripe
Supabase
NestJS
Mariya S.
Platja d'Aro, Spain
$35/hr
4.6
220 jobs
$1M+ earned on Upwork. 25+ years, 700+ projects, and deep JavaScript/TypeScript expertise across React, Next.js, Node.js & NestJS. I build and scale SaaS, web apps, automation, APIs, and complex platforms from architecture to production.
๐ Iโm a veteran Senior Full-Stack JavaScript/TypeScript Engineer, Full Stack JavaScript Developer, React Developer, Node.js Developer, and Web Developer with 25+ years of experience building scalable web applications, SaaS platforms, automation systems, browser extensions, and enterprise-grade JavaScript products.
I work across the full product lifecycle - from architecture and UI development to backend APIs, cloud infrastructure, integrations, performance optimization, and production support. My core stack includes React, React.js, Next.js, Node.js, NestJS, TypeScript, Vue.js, Angular, PostgreSQL, MongoDB, Redis, AWS, Docker, and serverless technologies.
Over the years, Iโve delivered 700+ projects across SaaS, eCommerce, Fintech, Web-to-Print, EdTech, Healthcare, CRM, AI automation, marketplaces, analytics, and enterprise platforms.
๐ RESULTS & EXPERIENCE
โ 25+ years in full stack development and web engineering
โ 700+ web, SaaS, React, Node.js, and automation projects delivered
โ Systems handling 10M+ API requests per month
โ 30+ applications scoring 90โ100 in Lighthouse audits
โ Backend performance improvements of up to 50%
โ Production experience with startups, scaling products, and enterprise systems
โ Advanced AWS serverless, event-driven, and real-time architecture
โ CI/CD and monorepo workflows that accelerate delivery and simplify maintenance
โก FRONTEND / REACT DEVELOPMENT
As a Senior React Developer and Frontend Developer, I build fast, maintainable interfaces for SaaS platforms, dashboards, marketplaces, internal tools, and customer-facing applications.
My frontend expertise includes:
โข React 18, React.js, Next.js 14+, Vue.js, Angular, TypeScript
โข SPA, SSR, ISR, PWA, and responsive web application development
โข Tailwind CSS, Material UI, SCSS, Bootstrap, and reusable UI systems
โข Complex dashboards, analytics interfaces, charts, and data visualization
โข Storybook, design systems, reusable component libraries, and UI architecture
โข Nx, Turborepo, Module Federation, and micro frontend architecture
โข Core Web Vitals, Lighthouse optimization, bundle reduction, and frontend performance
โข Mobile-first development and React Native integrations
โข Chrome extensions, browser extensions, content scripts, background services, and extension APIs
โข Puppeteer, Playwright, browser automation, scraping workflows, and automated testing
๐ NODE.JS / BACKEND DEVELOPMENT
As a Node.js Developer and Backend Developer, I design scalable APIs and backend systems that support complex business logic, real-time workflows, automation, and high-volume applications.
โข Node.js, NestJS, Express, Koa, Hapi
โข REST API and GraphQL development
โข PostgreSQL, MongoDB, MySQL, DynamoDB, Firebase, Redis
โข Prisma, Sequelize, TypeORM, Mongoose
โข JWT, OAuth, RBAC, secure authentication, and permissions
โข WebSockets, SocketIO, Redis, Kafka, and real-time infrastructure
โข BullMQ, AWS SQS, queues, workers, and background processing
โข Microservices and event-driven architecture
โข AWS Lambda, EventBridge, Step Functions, and serverless systems
โข ETL pipelines, analytics processing, and data aggregation
โข OpenAI API, Dialogflow, AI integrations, and automation workflows
โ๏ธ CLOUD, DEVOPS & DELIVERY
I build production-ready systems with reliable deployment, monitoring, and scaling workflows.
โข AWS, Docker, CloudFront, S3, Vercel, Firebase
โข GitHub Actions, GitLab CI/CD, Bitbucket Pipelines
โข AWS CDK and infrastructure as code
โข Sentry, Datadog, ELK Stack, logging, and monitoring
โข Redis caching, database optimization, and cloud cost reduction
โข Monorepos with Nx and Turborepo
โข Secure deployment and environment management
๐ PRODUCTS I BUILD
โข SaaS platforms and startup MVPs
โข AI-powered products and automation systems
โข eCommerce and marketplace platforms
โข CRM, ERP, and internal business tools
โข Fintech and analytics applications
โข Healthcare and EdTech platforms
โข Real-time dashboards and reporting systems
โข Browser extensions and browser automation tools
โข API integrations and workflow automation
โข Legacy platform modernization
โ๏ธ CORE TECHNOLOGIES
JavaScript, TypeScript, React, React.js, Next.js, Vue.js, Angular, Node.js, NestJS, Express, PostgreSQL, MongoDB, MySQL, Redis, AWS, Docker, Firebase, Vercel, GraphQL, WebSockets, Puppeteer, Playwright, Stripe, OpenAI API, SendGrid, PandaDoc.
โ LETโS BUILD A PRODUCT THAT CAN SCALE
Message me If you need a Senior Full Stack Developer, Full Stack JavaScript Developer, React Developer, Next.js Developer, Node.js Developer, Backend Developer, or Web Developer who can take ownership of both architecture and delivery, Iโd be glad to help.
Node.js
ExpressJS
JavaScript
MongoDB
Web Application
React
TypeScript
CSS
GraphQL
Front-End Development
Full-Stack Development
Redux
Next.js
React Native
PostgreSQL
REST API
API Integration
Python
HTML5
Vue.js
Viacheslav D.
EL CAMPELLO, ALICANTE/ALACANT, Spain
$50/hr
4.9
167 jobs
Hello! Iโm a Senior Full-Stack & AI Solutions Architect with 20+ years of experience in building high-impact digital products for startups, enterprises, and fast-growing SaaS companies.
As the CEO of Anadea, a European software development company with 100+ engineers, I personally lead AI transformation projects and help teams ship clean, scalable, and business-driven solutions - fast and efficiently.
๐ What I do best
I help companies turn complex ideas into working, profitable software. Over the years I've led and delivered projects in:
AI-powered SaaS platforms
Custom CRMs, ERPs, enterprise-grade systems
Real estate platforms & marketplaces
E-learning & digital training systems
E-commerce, booking platforms & multi-tenant solutions
MVPs built from scratch with rapid iteration cycles
My role blends deep technical expertise, system thinking, and strategic product guidance - ensuring every feature solves a real business problem.
๐ฅ AI Development & Automation Expertise
I specialize in designing and integrating AI across existing and new products:
๐ธ Custom AI chatbots & assistants (RAG, LangChain, multi-step reasoning)
๐ธ Semantic search, document processing, voice interfaces
๐ธ AI-driven workflows for customer support, onboarding, analytics
๐ธ Intelligent automation & process optimization for SaaS workflows
๐ธ AI-augmented full-stack apps (React/Next + Node/Nest + Python)
I oversee AI solutions from architecture โ prototyping โ production, ensuring reliability, cost-efficiency, and high-quality results.
๐ก AI Tools & Modern Engineering Stack
Actively working with:
โ๏ธ Botpress, Bolt.new, Lovable, Cursor
โ๏ธ Deepgram, ElevenLabs, Whisper
โ๏ธ LangChain, RAG pipelines, vector databases
โ๏ธ AWS / GCP / Vercel / Supabase deployments
โ๏ธ React, Next.js, Vue, Node.js, NestJS, Python, FastAPI
โ๏ธ PostgreSQL, Redis, MongoDB, cloud-native architectures
๐ง Engineering Leadership & Product Delivery
With my team, we provide end-to-end development:
Business analysis & product strategy
UI/UX (research โ wireframes โ high-end design)
Full-stack development
AI integration
QA & automation
Long-term support & scaling
Weโve delivered 300+ digital products across 40+ industries, including fintech, real estate, logistics, education, healthcare, and enterprise systems.
๐ Track Record
โ๏ธ 15+ years in full-cycle software engineering
โ๏ธ 100+ engineers in the team (AI, web, mobile, QA, DevOps)
โ๏ธ 250+ completed web & mobile projects
โ๏ธ Trusted by global clients in the US, EU, UK, UAE, Canada
โ๏ธ Featured in Clutch as a top-rated software development company
โ๏ธ Expertise in SaaS, CRM, ERP, AI agents, marketplaces & large platforms
๐ฏ What clients appreciate
Clear communication
Fast execution & strategic thinking
Reliable delivery with predictable timelines
Practical, not overcomplicated solutions
Focus on business value, not just code
๐ค AI Development & Automation
๐น Custom AI Chatbots ยท GPT-based Agents ยท Autonomous Agents
๐น RAG ยท LangChain ยท Vector Databases (Pinecone, Weaviate)
๐น AI Assistants ยท Multi-step Prompt Chains ยท LLM Orchestration
๐น Document Understanding ยท OCR ยท NLP Pipelines ยท Semantic Search
๐น Speech AI ยท Voice Interfaces (Whisper, Deepgram, ElevenLabs)
๐น Predictive Analytics ยท Forecasting Models ยท Recommendation Engines
๐น Workflow Automation ยท AI Process Optimization
๐น AI for SaaS ยท AI for E-commerce ยท AI for Real Estate
๐น AI UX ยท AI-first Systems ยท Hybrid AI Apps (React/Node/Python)
๐น OpenAI ยท Anthropic ยท Llama ยท Cloud AI Services (AWS/GCP)
๐ฅ Keywords for Upwork Search
AI Developer โข AI Engineer โข Full Stack Developer โข SaaS Developer โข GPT Developer โข RAG Expert โข AI Chatbot โข AI Agent โข LLM Engineer โข Workflow Automation โข React Developer โข Node.js Developer โข Python Developer โข SaaS Architect โข CTO-as-a-Service โข Startup MVP โข AI SaaS Platform โข Machine Learning โข Product Development โข AI Consultant
If youโre looking for a senior expert who can design, architect, and deliver AI-powered platforms from idea to production, letโs talk.
Node.js
JavaScript
API
Full-Stack Development
React
AI Development
Machine Learning
AI Platform
AI Chatbot
Python
Retrieval Augmented Generation
Amazon Web Services
Docker
DevOps
PostgreSQL
Supabase
LangChain
AI Agent Development
Generative AI
n8n
Aleksandra L.
Alicante, Spain
$47/hr
4.9
169 jobs
I am Aleksandra, leading a team of experienced full-stack developers specializing in AI-driven applications. We design and develop modern, scalable web and mobile solutions that integrate artificial intelligence, automation, and cloud technologies to optimize business operations.
With over 20+ years of collective experience, we have worked with startups and enterprises across industries like FinTech, Healthcare, eCommerce, and SaaS. Our expertise spans the entire development cycle, from initial concept and UI/UX design to backend architecture, AI integration, SRE (Site Reliability Engineering), and cloud deployment.
๐ 194+ successful projects completed on Upwork with global clients
๐ฒ $5M+ earned on Upwork through high-impact full-stack and AI solutions
โฑ 55,121+ hours billed, proving long-term client trust and engagement
๐ผ 600+ total projects delivered since 2000 across AI, web, and mobile
๐ 100% of developers hold engineering degrees, ensuring expert-level technical depth
๐ฉโ๐ป Advanced AI team includes Kaggle competition masters and top ML researchers
๐ 91%+ job success rate, reflecting top-tier performance and consistency
๐ 25+ AI-driven apps deployed in FinTech, EdTech, and HealthTech
๐ง 30+ machine learning models built and optimized for live environments
๐ 20+ industries served, from startups to Fortune 500 clients
๐งฑ Founded in 2000, bringing 24+ years of experience in software innovation
๐ 40+ React + Python full-stack solutions developed for scalable applications
โก High-load systems deployed to serve thousands of concurrent users
๐ Client ROI increased by up to 70% in AI automation projects
๐ฌ Featured in Forbes, MBN Magazine, and Helsinki Times for client success stories
Expertise:
Full-stack development for web and mobile applications
AI-powered solutions, including computer vision, natural language processing, and predictive analytics
Scalable cloud architecture using AWS, Google Cloud, and Azure
Real-time data processing and AI-driven automation
Platform Engineering and Infrastructure as Code (IaC)
GitOps workflows and CI/CD pipeline optimization
API development and third-party service integrations
Performance optimisation for high-traffic applications
FinOps and cloud cost optimisation
Secure and accessible web applications with SEO best practices
Technology Stack:
Frontend: React.js, Next.js, Vue.js, TypeScript
Backend: Node.js, Python (FastAPI, Django, Flask), Golang
AI & Machine Learning: TensorFlow, PyTorch, OpenAI API, Hugging Face, LLMOps
Databases: PostgreSQL, MongoDB, Redis, Firebase
Cloud & DevOps: AWS (Lambda, S3, DynamoDB, EC2), Docker, Kubernetes, Terraform, Helm, ArgoCD, GitHub Actions, GitLab CI/CD, Ansible, Prometheus, Grafana, ELK Stack
Tools & Platforms: Figma for UI/UX, Miro for user flow mapping, Webflow for no-code development
Why Work With Us?
We focus on delivering intelligent, future-proof applications that drive business growth. Our team ensures seamless collaboration, clean code, and scalable architecture that adapts to evolving needs. We are committed to clear communication, efficient execution, and long-term support.
If you are looking for a team that can build and scale AI-powered applications with a strong full-stack foundation, let's discuss your project.
๐ Keywords to find me:
AI Developer | Full-Stack Developer | AI Applications | React Developer | Node.js Developer | Python Developer | AI Integration | SaaS Developer | Web App Developer | Mobile App Developer | Scalable Applications | AI-Powered Software | Computer Vision | NLP Engineer | Machine Learning Engineer | Backend Developer | Frontend Developer | Cloud Developer | Automation Engineer | Cloud Architect | GCP | AWS | Azure | TensorFlow | PyTorch | OpenAI | Hugging Face | FastAPI | Django Developer | Flask Developer | Golang Developer | MLOps | LLMOps | DevOps | SRE | Site Reliability Engineer | Platform Engineer | Kubernetes | Docker | Helm | ArgoCD | Terraform | Infrastructure as Code | IaC | GitOps | CI/CD | GitHub Actions | GitLab CI/CD | Jenkins | Ansible | Prometheus | Grafana | Datadog | ELK Stack | DevSecOps | FinOps | AIOps | Observability | Monitoring | Service Mesh | Istio | Crossplane | OpenTelemetry | HashiCorp Vault | Multi-Cloud | Serverless | Figma | Webflow | Miro | Firebase Developer | MongoDB Developer | PostgreSQL | Redis | REST API Developer | API Integration | Predictive Analytics | AI in FinTech | AI in Healthcare | AI in eCommerce | SaaS Application | Intelligent Automation | Real-Time Data Processing | Cross-Platform Developer | SEO-Friendly Development | Secure Web Applications | Scalable Web Architecture | UI/UX Focused Developer | AI SaaS Developer | AI-Powered Mobile Apps | Full-Cycle Development | AI Solutions for Business | Enterprise Software | Startup MVP Development | AI Team Lead | Cloud-Native Applications | Serverless Architecture | AI-Driven Optimization | AI Workflow Automation | Real-Time AI Solutions | AI-Enhanced UX | AI Web App | AI-Powered Dash
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