10/06/2026 updated
DK
100 % available
Senior Full Stack Developer | React, Next.js, Node.js, SaaS & AI
Gdansk, Poland
Only remote
About me
With 6+ years of Salesforce and full-Stack experience and 300+ projects delivered, I’ve worked with startups, growing businesses, and enterprise organizations across different industries.
JavaScriptSoftware as a ServiceDevOpsNode.jsNext.jsShopifyReact.jsBackendSalesforce Commerce CloudFull Stack DevelopmentGraphQLReact NativeFront End Software DevelopmentNestJS
Full Stack Web Development
Expertise in building scalable web applications using React, Next.js, TypeScript, and Node.js, covering the entire development lifecycle from architecture and database design to frontend implementation and cloud deployment.
Backend & API Development
Proficiency in Node.js, NestJS, Express.js, and Fastify for building REST and GraphQL APIs, with experience in PostgreSQL, MongoDB, MySQL, Redis, and scalable backend architecture including authentication, authorization, and payment integrations.
SaaS Platform Development
Hands-on experience developing multi-tenant SaaS platforms including subscription and billing systems, user management, role-based access control, admin portals, analytics dashboards, and workflow automation.
Shopify & eCommerce Development
Development and customization of Shopify stores including custom themes, Shopify Liquid, App development, Admin and Storefront API integrations, Headless Shopify with React and Next.js, and custom eCommerce workflows.
AI-Powered Application Development
Integration of AI capabilities using OpenAI, ChatGPT, Claude, Anthropic, and Gemini, including AI assistants and agents, AI-powered search, RAG applications, AI workflow automation, and LLM-powered SaaS features.
Cloud & DevOps
Experience with AWS, Docker, GitHub Actions, CI/CD pipelines, Vercel, Cloudflare, Nginx, production deployment, performance optimization, and application scaling.
Third-Party Integrations
Integration of services such as Stripe, Twilio, SendGrid, authentication providers, payment systems, CRM/ERP systems, and various third-party APIs.
Frontend Technologies
Strong command of React.js, Next.js, TypeScript, JavaScript, React Query, Tailwind CSS, HTML5, and CSS3 for building modern, responsive user interfaces.
Expertise in building scalable web applications using React, Next.js, TypeScript, and Node.js, covering the entire development lifecycle from architecture and database design to frontend implementation and cloud deployment.
Backend & API Development
Proficiency in Node.js, NestJS, Express.js, and Fastify for building REST and GraphQL APIs, with experience in PostgreSQL, MongoDB, MySQL, Redis, and scalable backend architecture including authentication, authorization, and payment integrations.
SaaS Platform Development
Hands-on experience developing multi-tenant SaaS platforms including subscription and billing systems, user management, role-based access control, admin portals, analytics dashboards, and workflow automation.
Shopify & eCommerce Development
Development and customization of Shopify stores including custom themes, Shopify Liquid, App development, Admin and Storefront API integrations, Headless Shopify with React and Next.js, and custom eCommerce workflows.
AI-Powered Application Development
Integration of AI capabilities using OpenAI, ChatGPT, Claude, Anthropic, and Gemini, including AI assistants and agents, AI-powered search, RAG applications, AI workflow automation, and LLM-powered SaaS features.
Cloud & DevOps
Experience with AWS, Docker, GitHub Actions, CI/CD pipelines, Vercel, Cloudflare, Nginx, production deployment, performance optimization, and application scaling.
Third-Party Integrations
Integration of services such as Stripe, Twilio, SendGrid, authentication providers, payment systems, CRM/ERP systems, and various third-party APIs.
Frontend Technologies
Strong command of React.js, Next.js, TypeScript, JavaScript, React Query, Tailwind CSS, HTML5, and CSS3 for building modern, responsive user interfaces.
Experience
Professional experience5 - 10 years
Freelancer since2020
Languages
EnglishNative speaker