Freelance Full Stack Developer

🏢 Summary: Full Stack Developer role focused on building scalable Java and React applications, including backend microservices, responsive interfaces, REST integrations, and AWS-based operations. The offer includes long-term international project work, flexible hours, influence on architecture, and development opportunities. 🗂️ Requirements: 4–5+ years of professional software development experience, Commercial Java experience, Spring Framework and Spring Boot experience, React.js and TypeScript experience, JavaScript ES6+ knowledge, Production AWS experience, Microservices architecture knowledge, SQL and relational database experience, REST API integration experience, HTML5, CSS3/SCSS, responsive design, and cross-browser compatibility knowledge, Jest and React Testing Library experience, Modern frontend tooling and build process familiarity 📃 Skills: Java, React, Spring, SpringBoot, SQL, AWS, TypeScript, JavaScript, HTML5, CSS3, SCSS, Jest, Microservices, REST, ReactTestingLibrary 🏢 Description: ✅ Your responsibilities: Design, develop, and maintain scalable full stack applications using Java and React. Build and maintain backend services with Java, Spring Framework, Spring Boot, SQL, and AWS. Develop modern, reusable, and responsive user interfaces using React, TypeScript, and JavaScript. Design and implement scalable frontend architecture and reusable UI components. Collaborate closely with Product Owners, QA Engineers, and other development teams. Integrate frontend applications with REST APIs and backend microservices. Contribute to architectural decisions and technical discussions. Ensure application performance, scalability, security, and maintainability. Participate in code reviews, sprint planning, and Agile ceremonies. Support deployment automation, production operations, and troubleshooting. Mentor less experienced developers and promote engineering best practices. 🧠 Our requirements: Minimum 4–5 years of professional software development experience. Commercial experience with Java, Spring Framework, and Spring Boot. Commercial experience with React.js and TypeScript. Solid understanding of JavaScript (ES6+). Experience working with AWS in production environments. Understanding of microservices architecture. Hands-on experience with SQL and relational databases. Experience integrating and consuming REST APIs. Very good knowledge of HTML5, CSS3 / SCSS, responsive design, and cross-browser compatibility. Experience with frontend testing using Jest and React Testing Library. Familiarity with modern frontend tooling and build processes. Ability to work independently, take ownership of delivered solutions, and contribute to system design. Excellent communication skills and experience working in Agile environments ⭐ Nice to have: Experience with Kafka or other event-driven architectures. Knowledge of Hadoop or Apache Spark. Experience with Next.js. Experience with Redux, Zustand, or similar state management solutions. Previous experience in Healthcare or Life Sciences projects. 🌟 What we offer: Long-term cooperation on an international project. Flexible working hours. Opportunity to influence architecture and technical decisions. Modern technology stack. Supportive, collaborative engineering culture. Learning and development opportunities. Modern equipment and comfortable working environment.

🏢 Summary: Senior frontend/full-stack developer role focused on building resilient, enterprise-ready product features for a sports and health platform. The position involves React, TypeScript, Next.js, REST APIs, PostgreSQL, and close remote collaboration, with a hybrid schedule in Kraków. 🗂️ Requirements: 5+ years of professional development experience, Production experience with React and TypeScript, Production experience with Next.js App Router, REST API and data-validation experience, PostgreSQL and ORM experience, Ability to follow architectural documentation and team conventions, Git, code review, and Jira experience, Independent problem analysis and written feature planning/ADRs, Careful handling of healthcare data, schemas, and access logic, Strong written technical communication, Remote and asynchronous collaboration skills, Advanced English, Ability to complete a technical coding test without assistance, Availability to start within one month, Ability to work from the Kraków office 3 days per week 📃 Skills: React, TypeScript, Next.js, REST, Zod, PostgreSQL, Drizzle, Prisma, TypeORM, Git, Jira, Claude 🏢 Description: About the role You will be assisting in the understanding of, architecture, implementation, and quality of core Product Roadmap items intended to drive the project for our client forward. The ability to work with the team and collaborate is essential. You will have an immediate impact and be an early figure in the company today to help drive our growth. You will focus on solidifying our product and making it resilient as well as learning how to roll out enterprise-ready features. Required skills /knowledge and production experience/ React + TypeScript Next.js (App Router) — routing, server/client components, API routes REST API, data validation (example - Zod) PostgreSQL and ORM (Drizzle or similar — Prisma/TypeORM) Work according to the team's conventions and architectural documentation(ADR-y) — the ability to read and follow established standards before writing code Git, code review, ticketing (Jira) Coding with Claude /on daily basis/ Minimum of 5 years of professional experience developer with hands-on skills. Communication and other required skills Git, code review, ticketing (Jira) Independence in problem analysis and a willingness to plan before implementation (the project requires a written plan/ADR before each new feature). Accuracy and attention to detail—working with healthcare data requires caution when changing the schema and access logic. Good written communication—documentation, PR descriptions, tickets, and code review comments. Comfortable working in a distributed/remote team and asynchronous communication. Openness to feedback and a willingness to propose simpler solutions instead of over-engineering (the project explicitly avoids over-engineering). Sense of responsibility (ownership) for the delivered functionalities from design to implementation. Advanced English - hard must - daily calls with native CTO or CEO(weekly) . Ability to discuss technical problems, describe concept, architecture or planned feature. There's going to be (online or onsite in Krakow) technical coding test (without extra help) and English general and/or tech conversation. Awesome but not a must: Supabase (Auth, RLS, Postgres) AWS: S3, SQS, Lambda - designing or integrating with data processing pipelines (multipart upload, task queuing, workers) Terraform / IaC - ability to read infrastructure definitions (no need to write them yourself) Working with video / media data / large-volume files (e.g., recording processing, LiDAR, wearable data) Designing permission systems (RBAC) for multiple user roles OpenAPI / API contracts, documenting endpoints Experience in health, sports, telemedicine, or other sensitive/regulated data Application observability (Sentry, PostHog, or similar) Real-time integrations (chat/video SDKs like CometChat, WebSocket) Our benefits: Awesome and highly intense product /sports and health/ Private medical care and multisport card Flexible working hours (you can start between 8:00 -10:00 a.m.) Your choice of computer: Mac OS/Linux/Windows Upskilling budget English discussion classes every week Parking spot few mins from office Employee recommendation program. 🟢 The office is based in Kraków. We work 3 days from the office a week. 🟢 The process consists of 2 stages. We recruit remotely :) Ideal candidate should start within a month (no longer).

🏢 Summary: Full-time, fixed-term B2B contract for a Mid Fullstack Engineer to build and maintain a complex project and resource management web platform. The role covers scalable TypeScript development across React/Next.js frontend and Node.js/Express/PostgreSQL backend, including business workflows, permissions, dashboards, and data aggregation. Offers 100% remote work, flexible hours, and 85–120 PLN/h net + VAT. 🗂️ Requirements: 3+ years of commercial Fullstack Engineer experience, Commercial TypeScript experience across frontend and backend, React experience, Node.js and Express backend experience, PostgreSQL and relational database design experience, Modern web application experience with complex business logic, REST APIs, application architecture, and state management knowledge, Use of AI-powered coding assistants in daily workflow, Independent and cross-functional teamwork, Problem-solving and code-quality focus, Polish C1, English B2 📃 Skills: TypeScript, React, Next.js, Node.js, Express, PostgreSQL, REST, GitHub, Copilot, Cursor, ChatGPT, Claude 🏢 Description: The role We're looking for a Mid Fullstack Engineer with commercial experience building modern web applications using TypeScript and React . You'll join a product team developing a complex web platform that supports project and resource management, capacity planning, reporting, and collaboration across multiple user roles. The platform includes sophisticated business processes, role-based permissions, interconnected modules, and dashboards powered by aggregated data. You'll contribute to both frontend and backend development, building scalable features while collaborating closely with product managers, designers, and other engineers. This is a full-time (1 FTE), fixed-term contract from August/September 2026 until January/February 2026, dedicated to this product development project. What you'll do Develop and maintain full-stack features using TypeScript across both frontend and backend. Build user interfaces with React/Next.js and implement backend services using Node.js, Express, and PostgreSQL. Design and implement business logic related to project planning, resource management, capacity planning, and workflow automation. Develop and evolve data models, authorization mechanisms, and data aggregation logic. Build rich operational interfaces, including dashboards, tables, forms, filters, and user workflows tailored to different user roles. Collaborate with project managers, designers, and engineers to translate business requirements into scalable, high-quality solutions. Write clean, maintainable, and well-tested code while participating in code reviews. Contribute to architectural discussions and continuously improve the quality, performance, and maintainability of the platform. What we're looking for 3+ years of commercial experience as a Fullstack Engineer. Strong commercial experience with TypeScript across both frontend and backend development. Hands-on experience with React (Next.js is a plus). Commercial experience building backend applications with Node.js and Express. Experience working with PostgreSQL and relational database design. Comfortable using AI-powered coding assistants (e.g. GitHub Copilot, Cursor, ChatGPT, Claude) as part of the daily development workflow. Experience building and maintaining modern web applications with complex business logic. Good understanding of REST APIs, application architecture, and state management. Ability to work independently while collaborating effectively within a cross-functional team. Strong problem-solving skills and attention to code quality. Comfortable working in a bilingual environment (Polish C1, English B2). Nice to have Experience with Python and FastAPI. Experience designing permission models or role-based access control. Familiarity with automated testing and CI/CD pipelines. Experience working on SaaS or B2B products. What we offer 85-120 PLN/h netto + VAT, B2B 100% remote setup and flexible hours Interesting, meaningful projects – we only take on the ones we truly believe in :-)