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Akshay P.

Noida, India

$25/hr
5.0
206 jobs

I help startups and businesses build AI-powered SaaS platforms, marketplaces, and automation systems that reduce manual work and scale operations fast. I build production-ready web and mobile applications by combining 19+ years of hands-on development experience with AI-powered tools like Claudeโ€”shipping faster without compromising code quality, architecture, or UX. I also specialize in transforming outdated web apps into modern, AI-driven platforms with a clean, maintainable architecture so youโ€™re not dependent on developers. for every small change. Youโ€™ll be able to handle minor updates yourself using AI tools like Codex or Claude. If you're looking for someone who understands both technology AND business outcomes, you're in the right place. ๐Ÿš€ Core Expertise: AI-powered SaaS platforms Marketplace development (buyer/seller/admin systems) Business process automation Scalable backend architecture Custom dashboards & admin panels ๐Ÿง  How I Help You Whether you're launching an MVP or scaling an existing product, I can help you: โœ… Build your SaaS product from scratch โœ… Automate repetitive workflows using AI โœ… Develop secure and scalable backend systems โœ… Create seamless web & mobile applications โœ… Improve performance and reduce operational costs โš™๏ธ Tech Stack (Only What Matters) Mobile Application Development: We develop hybrid / cross-platform mobile applications using React Native CLI / EXPO, REDUX, and Flutter / Dart. PWA/progressive web application (React.js). Web Application Development: Full-Stack Development, Front-End Development, Back-End Development. MVP Development. SaaS development, Multitenancy Product Development. E-commerce & Social Media Websites. Front End Development: TypeScript, React.js, React remix, vite.js, Next.js, Vue.js, Nuxt.js, Tailwind CSS Back-end Development: Python (Django / flask / FastAPI), PHP (CodeIgniter / Laravel), Node.js (typescript), Express.js, Nest.js, fastify, Strapi Database: MongoDB, MySQL, PostgreSQL, SQLite, Amazon Redshift, MariaDB, AWS DynamoDB Tools & Technologies: Bitbucket, GitHub, Firebase, Websocket, Redis, Nginx, EC2, S3, RDS, and EBS (Elastic Block Store). ๐Ÿค Letโ€™s Work Together If youโ€™re looking for: A reliable long-term developer Someone who understands business, not just code Fast execution with scalable architecture ๐Ÿ‘‰ Letโ€™s discuss your project. My experience spans various domains, as outlined below. 1. Asset management system: a web application and mobile applications for iOS and Android. 2. Location live tracking and WiFi data scanning: a web application and mobile applications for iOS and Android. 3. Habit-tracking mobile application for iOS and Android. 4. Retreat and hotel booking engine: Web Application. 5. Ticket booking system with live seat selection: web application. 6. Shipping container calculator: web application. 7. Job board mobile application and web application. 8. SaaS for hospital care and home care companies: web application and mobile application. 9. Courses booking system: A web and mobile application along with a scheduling system. E-Learning PWA: Learning languages and mobile app development. 10. SaaS for project management and task management. 11. Boutique hotel and retreat website designing. 12. Equipment rental e-commerce website development. 13. Event posting and chat system: mobile application development. 14. Development of a Bible reading mobile application with a subscription system, supporting Apple and Google Pay. 15. Dummy flight and hotel ticket booking website for visa applications. 16. SaaS for creating surveys and managing user responses. 17. Real estate website development with MLS grid integration. 18. SaaS for companies managing work assignments, customer invoicing, and task calendars. 19. Food delivery Mobile application. 20. Facebook Graph API, Instagram Graph API, Twitter API, and LinkedIn API data management. 21. Dating website development. 22. Classified listing website development. 23. Travel deals e-commerce website 24. Grocery delivery mobile application development. 25. E-commerce website for selling fine wines. 26. CV and resume creation web application. 27. Employee payroll management web application. 28. Loan management system web application. 29. scheduling system for booking home inspection appointments along with a payment gateway and connection with gohighlevel CRM. 30. revenue management system โ€“ pulls data from QuickBooks, the Mercury API and the Stripe API and calculates the revenue. 31. car and bike parts / equipment / marketplace / vendor-buyer concept. 32. SMS marketing system that is connected with Twilio 33. Developing an MVP using AI-based web application builders such as Lovable, Replit, Claude AI, Claude-assisted development and Cursor AI. Please send a message OR invite me to your job so we can schedule a Zoom meeting.

  • Web Application
  • Node.js
  • Mobile App Development
  • React Native
  • React
  • Python
  • Laravel
  • JavaScript
  • iOS
  • Android
  • Django
  • Web Development
  • API
  • AI App Development
  • AI Development
  • Full-Stack Development
  • Next.js
  • SaaS Development
  • TypeScript
  • PHP
Valery M.

Bishkek, Kyrgyzstan

$35/hr
4.6
247 jobs

๐Ÿ† $3M+ Earned on Upwork โ€” Placing Me Among a Very Small Percentage of Freelancers on the Platform Struggling with a web platform that must scale, stay fast, and handle complex business logic? With 25+ years in full-stack development, I've delivered 600+ projects and helped build systems serving 20M+ users with 99.99% uptime across SaaS, ERP, marketplace, and data-platform products. I specialize in end-to-end architecture, React, PHP, Python, and API-first development. ๐Ÿš€ HOW I CAN HELP YOU Full-Stack Web Development Turn complex product ideas into scalable web platforms that support growth without constant rewrites. I've delivered 600+ projects across 40+ industries, including SaaS, ERP, CRM, marketplaces, and data platforms serving millions of users with 99.99% uptime. SaaS & ERP Development Launch subscription-based systems that streamline operations, automate workflows, and reduce manual overhead. My experience includes building: โ€ข Multi-tenant platforms โ€ข RBAC systems โ€ข Billing engines โ€ข Reporting dashboards โ€ข Audit trails ...helping businesses reduce operational overhead by 40%+. React & Next.js Frontend Development Increase engagement and conversion with fast, data-heavy interfaces that remain smooth under load. I build: โ€ข Dashboards โ€ข SPAs โ€ข PWAs โ€ข Admin panels โ€ข Analytics interfaces โ€ข Marketplace frontends PHP, Laravel & Symfony Backend Development Build backend architecture that supports growth, complex business logic, and seamless integrations. My expertise includes: โ€ข REST APIs โ€ข GraphQL APIs โ€ข Authentication & Authorization โ€ข MySQL โ€ข PostgreSQL โ€ข Redis โ€ข Laravel โ€ข Symfony WordPress Custom Plugin & Headless CMS Development Extend WordPress beyond standard templates so it supports custom workflows, improved performance, and modern content management. I build custom plugins and headless CMS solutions for businesses that need WordPress to function as a true applicationโ€”not just a brochure website. ๐Ÿ† RESULTS ๐Ÿ… 25+ years of hands-on full-stack development ๐Ÿ… 600+ projects delivered across 40+ industries ๐Ÿ… $3M+ earned on Upwork See full case studies in my portfolio below. โœ‰๏ธ MESSAGE ME ON UPWORK Looking for a full-stack developer to build or improve your SaaS, CRM, ERP, marketplace, or data platform? Message me on Upwork today for a free consultation and practical next steps. I typically respond within 4 hours and can offer quick turnaround for urgent projects. โš™๏ธ HOW I WORK I plan products using React, Node.js, and TypeScript, then architect the backend with PHP or Python backed by PostgreSQL or MySQL for reliable, scalable data flow. I deploy on AWS, automate releases with GitHub Actions, and use Docker to keep development and production environments consistent. For client-facing products, I integrate third-party APIs, optimize performance, and manage delivery through Jira, ensuring every stage remains transparent and predictable. I build full-stack web applications, architect scalable SaaS and marketplace platforms, integrate APIs, and design cloud infrastructure that is built to grow with your business.

  • Web Application
  • Full-Stack Development
  • Web Development
  • JavaScript
  • PHP
  • React
  • Node.js
  • TypeScript
  • Laravel
  • Vue.js
  • API Integration
  • Next.js
  • PostgreSQL
  • MySQL
  • Amazon Web Services
  • Python
  • Database Architecture
  • Redis
  • Docker
  • WordPress Development
Syed A.

Lahore, Pakistan

$30/hr
4.8
52 jobs

๐ŸŒ๐Ÿš€ MVP / SAAS Specialist Expertise in | AI Developer | RAG | LLM | AI Integration | Python | OpenAI API Integration | Artificial intelligence | Machine Learning | Langchain | Django React JavaScript | FastAPI | AI agent | AI App Development | AI bot | AI chatbot | AI Agent | Restful API | PostgresSQL | Botpress | PostHog | MCP Server | Multi-Agents/Multiple Agents | Voice AI ๐Ÿ”‘ ๐ˆ ๐›๐ฎ๐ข๐ฅ๐ ๐š๐ง๐ ๐๐ž๐ฉ๐ฅ๐จ๐ฒ ๐œ๐ฎ๐ฌ๐ญ๐จ๐ฆ ๐ฐ๐ž๐› ๐š๐ฉ๐ฉ๐ฅ๐ข๐œ๐š๐ญ๐ข๐จ๐ง๐ฌ, AI-Powered MVP, AI Healthcare Tools, AI Writing Tool, GPT Clone, Full Stack Application, Multi-Tenant ๐š๐ง๐ ๐ข๐ง๐ง๐จ๐ฏ๐š๐ญ๐ข๐ฏ๐ž ๐€๐ˆ ๐ฌ๐ฒ๐ฌ๐ญ๐ž๐ฆ๐ฌ ๐ญ๐ก๐š๐ญ ๐ฌ๐จ๐ฅ๐ฏ๐ž ๐œ๐จ๐ฆ๐ฉ๐ฅ๐ž๐ฑ ๐ฉ๐ซ๐จ๐›๐ฅ๐ž๐ฆ๐ฌ, ๐œ๐ซ๐ž๐š๐ญ๐ž ๐ง๐ž๐ฐ ๐ฏ๐š๐ฅ๐ฎ๐ž, ๐š๐ง๐ ๐ข๐ฆ๐ฉ๐ซ๐จ๐ฏ๐ž ๐ฎ๐ฌ๐ž๐ซ ๐ž๐ฑ๐ฉ๐ž๐ซ๐ข๐ž๐ง๐œ๐ž๐ฌ. ๐ŸŽ A 100% refund, if I'm unable to meet our agreed commitments. No questions asked! ๐Š๐ž๐ฒ ๐…๐š๐œ๐ญ๐ฌ: ๐Ÿง‘โ€๐Ÿ’ป 8+ years of experience as a Full Stack Developer and Artificial Intelligence Specialist ๐Ÿš€ 50+ market-winning projects launched โŒ› Around 600 hours on Upwork ๐ŸŽฏ Top-Rated on Upwork ๐ŸŒ‰๐ˆ'๐ฏ๐ž ๐ฌ๐จ๐ฅ๐ฏ๐ž๐ ๐ž๐ง๐ ๐ข๐ง๐ž๐ž๐ซ๐ข๐ง๐  ๐ฉ๐ซ๐จ๐›๐ฅ๐ž๐ฆ๐ฌ ๐Ÿ๐จ๐ซ ๐ญ๐จ๐ฉ ๐œ๐จ๐ฆ๐ฉ๐š๐ง๐ข๐ž๐ฌ ๐š๐ง๐ ๐ฌ๐ญ๐š๐ซ๐ญ๐ฎ๐ฉ๐ฌ ๐š๐ซ๐จ๐ฎ๐ง๐ ๐ญ๐ก๐ž ๐ ๐ฅ๐จ๐›๐ž โ˜‘๏ธ Under Armour โ˜‘๏ธ Snowflake โ˜‘๏ธ Estateza โ˜‘๏ธ SearchLook โ˜‘๏ธ Sparrowcharts ๐Ÿ’ก ๐–๐ก๐š๐ญ ๐œ๐š๐ง ๐ˆ ๐›๐ซ๐ข๐ง๐  ๐ญ๐จ ๐ฒ๐จ๐ฎ๐ซ ๐ญ๐š๐›๐ฅ๐ž? โ˜‘๏ธ Full Stack Development for robust and scalable web applications, including both front-end and back-end technologies โ˜‘๏ธ Custom Web and Application Development utilizing frameworks like Python, React, Django, React.js / Angular / Next.js / Nest / Nust / Golang and Node.js โ˜‘๏ธ Expertise in LLMs and ChatGPT integration to enhance application functionalities โ˜‘๏ธ Proficiency in RESTful APIs, GraphQL, and database management โ˜‘๏ธ Experience with cloud services like AWS, Azure, and Google Cloud for deployment and scaling โ˜‘๏ธ Strong problem-solving skills and ability to optimize user experiences and application performance ๐ŸŒŸ๐‡๐ž๐ซ๐ž'๐ฌ ๐ฐ๐ก๐š๐ญ ๐‚๐ฅ๐ข๐ž๐ง๐ญ๐ฌ ๐ก๐š๐ฏ๐ž ๐ญ๐จ ๐ฌ๐š๐ฒ ๐š๐›๐จ๐ฎ๐ญ ๐ฆ๐ž: ๐ŸŒŸ Ali Hamza is in the top tier of software developers and data engineers. He is far more than an implementer; he is a strong architect. During this project set, Usama worked on data from major US corporations ๐ŸŒŸ One of the best developers I have ever worked with. He is always on time and does exactly what he says he will do. I could not recommend him enough. ๐ŸŽฏ ๐ˆ ๐ฉ๐จ๐ฌ๐ฌ๐ž๐ฌ ๐ž๐ฑ๐ฉ๐ž๐ซ๐ญ๐ข๐ฌ๐ž ๐ข๐ง ๐ญ๐ก๐ž ๐Ÿ๐จ๐ฅ๐ฅ๐จ๐ฐ๐ข๐ง๐  ๐๐จ๐ฆ๐š๐ข๐ง๐ฌ โ˜‘๏ธ Full Stack Development: โ˜‘๏ธ Backend: โ˜‘๏ธ Python โ˜‘๏ธ Django โ˜‘๏ธ Flask โ˜‘๏ธ NodeJs, Express.js โ˜‘๏ธ Rest API, SOAP โ˜‘๏ธ Websocket โ˜‘๏ธ Third party integration โ˜‘๏ธ Frontend: โ˜‘๏ธ Html5, Css3, Bootstrap โ˜‘๏ธ Javascript โ˜‘๏ธ ReactJs, Angular โ˜‘๏ธ VueJs โ˜‘๏ธ NextJs, NuxtJs โ˜‘๏ธ Ajax, JSON, XML, XHTML, SVG, Canvas โ˜‘๏ธ API integration, OpenAI API โ˜‘๏ธ DevOps: โ˜‘๏ธ CI/CD Pipelines โ˜‘๏ธ IaC โ˜‘๏ธ Docker โ˜‘๏ธ Kubernetes / Terraform โ˜‘๏ธ Elasticsearch โ˜‘๏ธ Cloud Computing (Azure, AWS, Google Cloud) โ˜‘๏ธ Version Control (Git, GitHub) โ˜‘๏ธ Containerization + Orchestration (Docker, Kubernetes) โ˜‘๏ธ Spring Boot / Java, Microservices Architecture โ˜‘๏ธ Real-time / Streaming / Event-driven architectures โ˜‘๏ธ Session Recordings / Session Replays โ˜‘๏ธ GraphQL / gRPC โ˜‘๏ธ Kafka / Redpanda (real-time streaming) โ˜‘๏ธ Generative Artificial Intelligence (GenAI) โ˜‘๏ธ Large Language Models (LLMs) โ˜‘๏ธ Natural Language Processing (NLP) โ˜‘๏ธ ChatBots and Virtual Assistants โ˜‘๏ธ Text to Image Modelling โ˜‘๏ธ Vector Databases โ˜‘๏ธ Retrieval-Augmented Generation (RAG) โ˜‘๏ธ ChatGPT โ˜‘๏ธ OpenAI โ˜‘๏ธ AI/ML (Artificial Intelligence + Machine Learning) โ˜‘๏ธ Multimodal AI / NLP โ˜‘๏ธ Agentic AI / Autonomous Agents โ˜‘๏ธ โ€œVibe Codingโ€ / AI-first / prompt-driven dev workflows โ˜‘๏ธ Explainable AI / Ethical, Sustainable AI โ˜‘๏ธ Edge AI / On-device / Federated Learning โ˜‘๏ธ Web Scraping โ˜‘๏ธ Data Extraction โ˜‘๏ธ Data Scraping โ˜‘๏ธ Scrapy โ˜‘๏ธ Selenium โ˜‘๏ธ Beautiful Soup โ˜‘๏ธ Requests โ˜‘๏ธ Deployment and scheduling the scraping scripts on server โ˜‘๏ธ PostHog / Mixpanel / Amplitude / Segment (Twilio Segment) โ˜‘๏ธ OpenTelemetry (Datadog / Grafana / Sentry โ˜‘๏ธ LaunchDarkly / GrowthBook / VWO / Optimizely / Klaviyo โ˜‘๏ธ Airbyte / Fivetran / DBT โ˜‘๏ธ Auth0 / Clerk / SuperTokens / Google Auth โ˜‘๏ธ Stripe / Paddle โ˜‘๏ธ Plaid AI + Analytics Integrations โ˜‘๏ธ LangSmith / LangFuse โ€“ Observability and evaluation layer for LLM apps. โ˜‘๏ธ Weaviate / Pinecone / Qdrant โ€“ Vector DBs for AI features with analytics hooks. โ˜‘๏ธ Whylabs / Arize AI โ€“ ML observability & monitoring (similar to PostHog but for models). I am a Fullstack AI Developer - Python Django, React, Flask, API Integration I can help you to build: โšก Fast MVP Development (AI-Powered) โœ… โšก AI Powered SAAS Applications โœ… โšก AI Agent RAG Systems | AI Chatbots โœ… โšก Open AI API Integrations / LLM โœ… โšก Full stack Development (AI/ML, Django, React) โœ… โšก AI Workflows Automation โšก Voice AI tools Thank you for visiting my profile. Looking forward to working with you! I will ๐Ÿ’ฒREFUND ๐Ÿ’ฒ, if your expectation wont meet. For reference, you can see my work and testimonials below. Lets Chat!

  • Web Application
  • Artificial Intelligence
  • Machine Learning
  • AI Agent Development
  • OpenAI API
  • AI Development
  • Django
  • Python
  • Retrieval Augmented Generation
  • API Integration
  • JavaScript
  • React
  • PostgreSQL
  • Large Language Model
  • Chatbot Development
  • LangChain
  • API
  • LLM Prompt Engineering
  • AI App Development
  • FastAPI
Yevhen L.

Odesa, Ukraine

$45/hr
4.8
1,107 jobs

๐Ÿฅ‡ TOP 0,01% BEST DESIGNERS ON UPWORK ๐Ÿฅ‡ CERTIFIED BY GOOGLE & UPWORK ๐Ÿฅ‡ 900+ SUCCESSFUL PROJECTS COMPLETED ๐Ÿฅ‡ RECOGNIZED PORTFOLIO: 25,500+ DRIBBBLE & 9,600+ BEHANCE FOLLOWERS ๐ŸŽฏ TRUSTED BY: GOOGLE, UBER, NESTLร‰, P&G, AB INBEV, RHB Hi, I'm Yev. I partner with founders and product teams from Seed to Series B to take products from 0 to 1. As an experienced UX/UI designer and UI UX Designer, I don't just design screens โ€” I build intuitive, high-performing digital products that drive growth. With over 10 years of experience in product design, creative direction, and web development, I bridge the gap between user needs and business goals. โœ… What I can bring to your product as a UX/UI designer. โ‡๏ธ Strategic User Experience Design: As a Senior UX/UI designer, I create user experience strategies that boost usability and drive engagement. My UX designer approach (including UX research and user flows) has led to conversion increases of up to 150% for previous clients. I specialize in UIUX that makes complex systems simple. โ‡๏ธ Expert Web Design & Mobile App Design: I specialize in mobile ui ux, iOS/Android app design, and responsive web design. I ensure a seamless user interface with a consistent look and feel across all platforms. Whether it's a mobile app ui ux designer task or a complex web design, I deliver pixel-perfect results as your lead UX/UI designer. โ‡๏ธ Figma Design & Prototyping: As a Figma designer and expert UX/UI designer, I deliver high-fidelity wireframes, interactive prototypes, and design systems. Iโ€™ve delivered 5,000+ wireframes, helping streamline web development and reduce costly revisions. My expertise includes Figma ui designer roles and creating figma app design from scratch. โ‡๏ธ SaaS & Ecommerce Expertise: Whether you need a UI UX designer SaaS Figma specialist for complex ui ux dashboards or a Shopify website design that converts, I focus on layouts that drive revenue. I am a shopify website designer and wordpress website designer who understands how a UX/UI designer impacts business metrics. โ‡๏ธ Technical Synergy & Handoff: I understand the bridge between design and code. I provide assets for Figma to React, Figma to Webflow, Figma to WordPress, Figma to Shopify, and Figma to HTML/CSS implementation. This ensures your website design is implemented exactly as planned by a technical UX/UI designer. โœ… My achievements in numbers โ‡๏ธ UX/UI designer for Logistics SaaS (React): Improved order processing efficiency by 200%. Reduced human error by 50% through enhanced user interface design. Cut manual work by 70%, boosting productivity for SaaS platforms. โ‡๏ธ Mobile App UI UX Designer for Health/Fintech: 2x user retention by redesigning the mobile app design. 3x onboarding speed through streamlined user flows and interactive prototyping. โœ… My full range of services. I cover a wide range of specialized design services to ensure your brand stands out. Web & Landing Pages: Landing page web design, landing page web designer, figma landing page, and wix web design. Platform Specialist: Wix website designer, squarespace website design, webflow ui ux, and elementor expert. Graphic Design: Graphic designer illustrator, logo design, motion graphic designer, social media graphic designer, and canva graphic designer. Niche Expertise: UX/UI designer AI, crypto game ui ux designer, saas ui designer, and industrial designer logic. E-commerce: UI UX designer ecommerce, shopify website design, wordpress website design, and website developer collaboration. โœ… My design process: Discovery & UX Research: Understanding your product manager goals and user pain points. Wireframing & Strategy: Creating ui ux web designer blueprints and wireframes. UI Design & Branding: Developing the visual identity, ui graphics, and icons. Prototyping: Building figma ui ux interactive models to test user journeys. Development Support: Providing figma to html or figma to react specs for your web developer or full stack website developer. โœ… Why choose me? I am a professional UX/UI designer with extensive skills in Graphic design. I create brand-aligned digital experiences, provide logo design services, and create a strong visual identity. With 25,500+ Dribbble and 9,600+ Behance followers, my work is recognized by the global design community. UI/UX Figma Expert: Deep knowledge of auto-layout, components, and variables. Full Stack Mindset: I work closely with website developers, virtual assistants, and facebook ads teams to ensure the design supports marketing and tech. Whether you need a UI UX designer figma, a mobile ui ux designer, or a webflow specialist, I have the experience to take your product to the next level. I specialize in UIUX designer tasks that involve product designer thinking and ux designer empathy. Ready to boost your conversions and drive business growth? Hire a professional UX/UI designer today โ€“ Letโ€™s connect! โ˜Ž๏ธ Last updated: 11.05.2026

  • Figma
  • Web Design
  • UX & UI
  • Wireframing
  • Graphic Design
  • Prototyping
  • UI/UX Prototyping
  • Usability Testing
  • Adobe Photoshop
  • Mobile UI Design
  • Mobile App Design
  • User Flow
  • UI Graphics
  • User Experience
  • User Interface Design
  • UX Research
  • User Experience Design
  • WordPress
  • Webflow
  • UX & UI Design
Elahe A.

Dubai, United Arab Emirates

$40/hr
5.0
10 jobs

With over 15 years of experience, I donโ€™t just write code; I engineer clean, scalable solutions. I always follow one simple rule: keep everything clear and easy to use. The software I create is designed to feel intuitive from the first moment, helping users engage with the product naturally without confusion. My main strength is backend development with C#, ASP.NET Core and Next.js, where I handle project analysis, design clean architectures, and build reliable systems. I work comfortably with APIs for smooth module communication and have solid expertise in SQL database design and query optimization. My core skills include: โ€ข C# .NET Framework and Windows development โ€ข Warehouse management & ERP system and IoT development โ€ข Integrated business systems design (e.g. accounting, inventory, sales) โ€ข ASP.NET & MVC, ASP.NET Core โ€ข API Integration โ€ข Microsoft SQL Server & PostgreSQL & Database Architecture โ€ข Next.js & Tailwind & Django โ€ข Supabase โ€ข Solutions Architect I analyze your project, design a clean architecture, and deliver software that works flawlessly. Always learning and expanding my skillset ๐Ÿ‘Œ

  • Web Application
  • Desktop Application
  • International Development
  • Ecommerce Website
  • ASP.NET Core
  • C#
  • SQL
  • PostgreSQL
  • Next.js
  • TypeScript
  • Tailwind CSS
  • API
  • DevExpress
  • No-Code Website
  • Supabase
  • Full-Stack Development
  • AI Development
  • Vercel
  • SaaS Development
Ivan K.

Zagreb, Croatia

$45/hr
4.6
160 jobs

Need a full-stack product built fast without sacrificing scalability? With 15 years as a Full-Stack Developer and AI Engineer, Iโ€™ve delivered 16k+ hours and $1M+ earnings across web and mobile products. For startups and SaaS teams, I build React, Next.js, Node.js, and Flutter solutions that launch cleanly and scale confidently. ๐ŸŽฏ HOW I CAN HELP YOU FULL-STACK WEB APPLICATION DEVELOPMENT Launch scalable web products that convert users faster and support long-term growth. I build React, Next.js, Node.js, and TypeScript applications with architecture choices that have supported $1M+ in Upwork earnings and 100% Job Success. AI AGENT AND OPENAI INTEGRATION Add intelligent features that automate work, reduce manual effort, and create new product value. I integrate OpenAI APIs and AI workflows into existing platforms to accelerate delivery and turn ideas into usable AI-powered products. MOBILE APP DEVELOPMENT Ship iOS and Android apps that give users a smooth experience across devices and help you reach more customers. I develop with Flutter, React Native, Swift, and Kotlin, with proven experience delivering apps published to both Apple and Google app stores. SAAS PLATFORM DEVELOPMENT Turn complex ideas into secure, scalable SaaS products that are ready to monetize. I have built multi-tenant platforms with authentication, billing, APIs, and dashboards for startups and enterprise teams in as little as MVP timelines. API AND BACKEND ENGINEERING Increase system stability, speed up integrations, and support growth with robust backend foundations. I design Node.js, NestJS, Express, PostgreSQL, and cloud-based systems that handle real-world product demands across web, mobile, and AI features. ๐Ÿ† RESULTS "Thanks to Cinnamon's efforts, the app's server response times were excellent, and the end client was thrilled with the results. The team was responsive and pragmatic in responding to needs, communicating via virtual meetings, emails, and messages. Their talented engineering team was impressive." โ€“ Gregory W., Founder, Mojave Interactive LLC "Thanks to Cinnamon's work, the client has seen a 25% higher completion rate and 40% less completion time. The pricing calculators have reduced the error rates by 50%. The team delivers timely items, responds quickly to messages, and addresses requests effectively. Their support is unique." โ€“ Premnath M., Head of Software Development Digital Bank, BAWAG AG "The Android app has thousands of downloads and impressive online ratings, which reflects Cinnamon Agency's technical expertise. The team is willing to work long hours to meet deadlines. They excel at project management and have a robust reporting system in place." โ€“ Garin Toren., Founder, Ping ๐ŸŽ– JavaScript Algorithms and Data Structures Certification ๐ŸŽ– React Developer Certification ๐ŸŽ– AI Engineering and LLM Integration Certification See full case studies in my portfolio below. ๐Ÿค ๐—š๐—˜๐—ง ๐—œ๐—ก ๐—ง๐—ข๐—จ๐—–๐—› Have an app idea or product to launch? Message me on Upwork today for a free consultation and a clear plan to move forward. I typically respond within 4 hours and can offer quick turnaround for urgent projects. ๐—›๐—ผ๐˜„ ๐—œ ๐—ช๐—ผ๐—ฟ๐—ธ I build in React, Next.js, and TypeScript to ship fast, maintainable web apps, then use Node.js, PostgreSQL, and AWS to keep the backend reliable and scalable. For AI features, I integrate OpenAI APIs and Cursor into workflows that automate tasks and add real product value. I also use Flutter when a project needs a polished cross-platform mobile app. I build full-stack web applications with React and Next.js, integrate Node.js APIs, and deliver mobile app development with Flutter and AI development that scales.

  • Web Application
  • Full-Stack Development
  • Web Development
  • React
  • JavaScript
  • Node.js
  • API Integration
  • Next.js
  • Mobile App Development
  • AI Development
  • Amazon Web Services
  • PostgreSQL
  • TypeScript
  • Firebase
  • API
  • PHP
  • Automation
  • iOS Development
  • Ethereum
  • Web Design

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Don't just take our word for it

Web application freelancer hiring guide

Web application freelancers design, build, and deploy interactive software that runs in web browsers, handling everything from user-facing interfaces to server-side logic and database integrations across industries like e-commerce, software as a service (SaaS), healthcare, and finance. Whether you need a customer portal, internal dashboard, or minimum viable product (MVP), hiring a web application freelancer can help you define project requirements, select the right tech stack, and deliver a working application aligned with your business goals.

What does a web application freelancer do?

A web application freelancer builds, tests, and maintains browser-based software that captures user input, processes data, and delivers dynamic responses. Unlike static websites, web apps typically require JavaScript frameworks (React, Angular, Vue), databases, application programming interfaces (APIs), and server-side logic. Depending on the project, you may hire a front-end specialist, back-end developer, or full-stack developer who handles both.

Common responsibilities include architecting application structure, writing and testing code, integrating third-party services (payment gateways, authentication, analytics), optimizing performance, and ensuring cross-browser compatibility. Typical deliverables include functional UI components, API endpoints, database schemas, deployment configurations, and documentation. On larger projects, web app freelancers often collaborate with user interface (UI) and user experience (UX) designers who create wireframes and visual designs, product managers who define requirements, and quality assurance (QA) testers who verify functionality before launch.

How to hire a web application freelancer on Upwork

Hiring a web application freelancer on Upwork follows a clear process: post a job with defined requirements, evaluate candidates based on relevant experience, interview for technical and collaboration fit, and agree on scope before starting work.

Step 1: Post a job

Start by describing what you need built, your preferred tech stack, timeline, and budget. A strong job post includes:

  • Scope of work and specific deliverables (features, pages, integrations)

  • Preferred tech stack (frameworks, databases, deployment environment)

  • Project timeline and milestone expectations

  • Budget preference (hourly or fixed-price)

  • Any required background (industry experience, security requirements)

Use the Job Post Generator, powered by Umaโ„ข, Upwork's Mindful AI, to draft a clear job description. Describe your project in a few sentences, and Uma will generate a customizable post for web application freelancers. 

Step 2: Evaluate candidates

When evaluating candidates, review proposals and shortlist them based on evidence of similar work. Use the following as your screening checklist:

  • Portfolio or case studies showing comparable web app builds (dashboards, e-commerce, SaaS)

  • Framework and database experience matching your stack requirements

  • Client feedback and reviews indicating delivery quality and communication

  • Proposed approach

    • Does their plan address your requirements and potential challenges?

  • Availability and time zone overlap if real-time collaboration matters

If you use Upwork Business Plus, curated shortlists can help you start from a smaller set of stronger matches. For more guidance, see how to evaluate developer skills.

Step 3: Interview qualified candidates

Use interviews to assess technical depth, problem-solving, and communication. Consider asking:

  • Can you walk through a similar web application you built and describe the architecture decisions?

  • How do you approach testing and quality assurance for web apps?

  • What's your process for handling scope changes or feature requests mid-project?

  • How do you structure API endpoints and manage database optimization?

Upwork supports video meetings for remote interviews, and Instant Interviews can help you schedule a call quickly from the candidates you are already considering. For additional question ideas, see common web developer interview questions for remote hiring.

Step 4: Agree on scope and begin work

Before starting a contract, confirm these details:

  • Final deliverables and what's included (and excluded)

  • Milestones for fixed-price projects (e.g., UI complete, API functional, final QA)

  • Success criteria: How will you verify the application works as expected?

  • Revision process: How many rounds of feedback are included?

On Upwork for fixed-price contracts, project funds are held and released upon milestone approval. This structure supports phased delivery, such as front-end first, then back-end integration, then deployment and QA review.

How much does hiring a web application freelancer cost?

The cost of hiring a web application freelancer depends primarily on project scope, required features, technology stack, and freelancer experience. Use these standard web app development cost estimates to guide your project budgeting. You can also see cost factors for web developers as a starting point.

Small fixed-price project

$300โ€“$800/project

Entry-level to mid-level
  • User-friendly front-end component (Vue.js or React
  • API connection to a database (Node.js + MongoDB)
  • Mobile-responsive landing page with form submission

Medium fixed-price project

$800โ€“$2,000/project

Mid-level
  • Custom content management system (React + Node.js )
  • Customer dashboard with authentication and data visualization
  • Third-party payment API integration

Large fixed-price project

$2,000โ€“$6,000/project

Senior-level
  • Full-stack e-commerce web application (MERN stack)
  • Production deployment with scalability setup
  • Expanded testing, QA, and technical documentation

Frequently asked questions

Is hiring a web application freelancer worth it?

Hiring a web application freelancer is often worth it when your project requires interactive functionality, user data handling, third-party integrations, and ongoing iteration. A specialist brings repeatable engineering practices that many business owners do not have time to build while also running the business, such as setting up automated tests, defining secure authentication flows, and creating deployable environments with rollback paths.

OWASPโ€™s Top 10 highlights common web application risks, which is a useful reminder that even โ€œsmallโ€ apps benefit from professional implementation and security-minded review.

What's the difference between a web app and a website?

A web application captures user input, processes data, and delivers dynamic responses, often using JavaScript frameworks and databases. A static website primarily displays content without complex user interactions or data processing. If your project involves user accounts, dashboards, forms that save data, or real-time updates, you likely need a web application freelancer rather than a general web designer.

Should I hire a full-stack developer or separate specialists?

Whether you hire a full-stack developer or separate specialists should be guided by your projectโ€™s scope and budget. A full-stack developer can handle both front-end and back-end work, which simplifies coordination for smaller projects. For larger builds with complex UI requirements or heavy back-end logic, a separate specialist may have a stronger skill set in their respective areas.

How do I know if a freelancer's experience matches my project?

To know if a freelancerโ€™s experience matches your project, review their portfolio for similar builds: same type of application (e-commerce, SaaS, dashboard), comparable tech stack, and similar complexity level. Ask about specific challenges they solved on past projects and how they approached testing and deployment. Strong candidates can explain their process clearly and point to concrete results.