Senior Frontend Developer - Freelance Opportunity

Join Netguru, a leader in the digital commerce landscape, as we partner with renowned brands to elevate their B2B solutions, marketplaces, and retail ecosystems. Since our inception in 2008, we have empowered businesses with state-of-the-art technology, AI-driven personalization, and top-notch engineering and design teams. As a certified B Corporation®, we take pride in our collaborations with major brands such as IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted.How does freelancing work at Netguru?As a freelancer at Netguru, you have the flexibility to choose your working hours, location, and project tasks. We align your skills with suitable projects, providing you access to diverse opportunities across various industries. This not only enhances your experience but also allows you to broaden your skill set.Moreover, Netguru freelancers can engage in full-time collaborations, truly becoming integral members of our team. Are you ready to make a significant impact? Join us, and let’s create stunning software together.Currently, we are seeking a Senior Frontend Developer to join our team.

Join our dynamic team as a Senior Frontend Developer at evolution in Warsaw! We are looking for a talented individual with a passion for building responsive and high-performance web applications. You will collaborate with cross-functional teams to deliver exceptional user experiences and implement innovative solutions.

Join trimetis as we embark on an exciting journey to completely transform the internal application of one of Europe’s leading transport services companies. With a focus on innovation, we are reimagining their customer care tool, a web application that enhances operational efficiency and user experience. Collaborating across diverse teams, we aim to revolutionize the client's business from the inside out.Industry: Payment Solutions, ElectromobilityProduct: Customer Care Tool (Web Application)Project Methodology: AgileContract Type: B2B or Employment ContractWork Arrangement: Full-time, 100% Remote from PolandStart Date: February/March 2026

Join our dynamic team at Shiji Group as a Senior Frontend Developer, where you will play a pivotal role in crafting and enhancing user interfaces for our innovative software products. We are looking for a talented individual who is passionate about frontend technologies and has a keen eye for design and functionality.Your responsibilities will include collaborating with cross-functional teams to define, design, and ship new features, ensuring the performance and quality of our applications, and troubleshooting and debugging complex issues.

MasterBorn is hiring a Junior Frontend Developer with a focus on React.js. This role allows for remote work or joining the team onsite in Wrocław. Collaboration and practical learning are central to how this team works together. Role overview This position centers on building and refining web applications using React.js. The team welcomes new ideas and encourages open communication as part of daily work. What you will do Work with experienced developers to develop and enhance web applications with React.js Help design and implement user-friendly interfaces across various projects Share input and solutions within a supportive, collaborative group Work location This role can be performed remotely or from the Wrocław office.

Join Netguru, a pioneering force in digital commerce, as we assist renowned brands in modernizing their B2B solutions, marketplaces, and retail ecosystems. Since our inception in 2008, we have empowered businesses through innovative technology, AI-driven personalization, and exceptional engineering and design teams. As a certified B Corporation®, we proudly serve major brands such as IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted.We are currently seeking a Senior Backend Engineer with robust architectural expertise to engage in a long-term project for a European client in the laboratory and biotech sector. This position is a single-developer project, requiring close collaboration with the client’s internal teams and laboratory stakeholders to clarify requirements, outline the project scope, and enhance existing backend processes. Strong communication skills are vital, as you will frequently participate in technical discussions with LIMS and laboratory teams. Your role will encompass hands-on development, legacy code refactoring, and contributing to a scalable, well-structured backend architecture. Please note that candidates must be based in the EU due to client stipulations.Position: Senior Backend Engineer (Java / Architecture)Contract: Freelance / B2B – Remote (EU Only)Rate: 36–50 EUR/hourLanguage: English C1Key ResponsibilitiesOperate independently as the sole backend engineer on the project.Refactor and modernize legacy backend systems.Enhance and expand existing microservices and backend integrations.Maintain and develop REST and SOAP interfaces.Engage with laboratory teams and LIMS stakeholders to define requirements.Guarantee stable operation of backend services in an on-premise Kubernetes environment.Work collaboratively with internal client teams to ensure architectural consistency.QualificationsTechnical Skills & ExperienceExtensive experience with Java (Spring / Spring Boot).Strong architectural and problem-solving abilities.Proficient in designing and maintaining REST APIs.Familiarity with SOAP services.Experience in microservices environments.Hands-on experience with Kubernetes (preferably on-premise setups).Background in working with or integrating LIMS systems.Solid understanding of refactoring and modernizing legacy code.Excellent communication skills for direct collaboration with laboratory stakeholders.Proficiency in English at C1 level.Must be based in the European Union.BenefitsIn return, we offer:100% remote, flexible work environment;Access to cutting-edge technology and tools;Opportunities for professional development.

Role overview Cupid Media seeks a Senior Frontend Developer in Poland to strengthen and expand its online platforms for singles worldwide. This position centers on enhancing the user experience and supporting the company's mission to connect people globally. What you will do Collaborate with cross-functional teams to design, develop, and launch new features for web platforms. Use frontend development expertise to deliver smooth and engaging experiences for users. Contribute to solutions that reach a diverse, international audience. Location This role is located in Poland.

Role overview SmartRecruiters seeks a Senior Frontend Engineer in Kraków to focus on the Design System and Frontend Platform. The role centers on building web applications that are both scalable and maintainable. Close collaboration with designers and product teams is essential to continually improve user experience across the platform. What you will do Develop and maintain the company design system and core frontend platform. Work with designers and product stakeholders to deliver a consistent, accessible user interface. Create solutions that follow established design principles and standards. Integrate frontend components with backend services by partnering with backend teams. Take part in shaping the future of frontend architecture at SmartRecruiters. Location This position is based in Kraków.

Veeam Software, the leading global provider of data resilience solutions, empowers businesses to maintain control over their data anytime, anywhere. We specialize in data backup, recovery, portability, security, and intelligence, supporting over 550,000 customers globally who trust us to keep their operations running smoothly. Join our mission as we innovate and create impactful solutions for some of the world's largest brands. Embrace the future of data resilience and move forward with us boldly.About the RoleWe are seeking a talented and experienced Frontend Engineer to become part of the Veeam Data Cloud (VDC) engineering team. In this role, you will collaborate with a global team to develop next-generation data protection services aimed at enhancing data resilience for our customers.This is a unique opportunity to engage in greenfield projects, creating features from the ground up that will be deployed and utilized globally.What You’ll DoDesign and develop highly responsive user interface components for web applications using React.Test and troubleshoot web applications. Design and maintain unit testing and end-to-end testing frameworks.Create reusable components and front-end libraries for future use.Collaborate with other engineering teams to discuss requirements, design, and implementation.What You’ll Bring5+ years of experience in developing enterprise solutions using React, JavaScript, HTML, and CSS.Proficiency in TypeScript.Strong understanding of computer science fundamentals, including data structures and algorithms.A passion for code quality, extensibility, coding standards, testing, and automation.A results-driven mindset with a focus on impact and outcomes.

Fraud Warning: Beware of potential scams posing as legitimate job opportunities. To ensure your application is considered, please apply only through the official Sensor Tower website or directly through our authorized profiles on platforms like LinkedIn, Indeed, BuiltIn, or Hackajob. Sensor Tower will never request payment, credit card, or bank account information during the application process. All official communications will originate from email addresses ending in sensortower.com. Interviews will be conducted via phone or Zoom, and no conversations will shift to external email or text platforms. If you encounter any issues, please reach out to us. Remember to attach your resume when applying.Recruitment Agencies: Sensor Tower does not accept unsolicited resumes from third-party agencies. Please refrain from sending resumes to our job alias, employees, or any other location. Sensor Tower will not cover fees related to unsolicited resumes and will not compensate agencies without a signed agreement.About This Role:Are you excited by the dynamic environment of a startup?Do you have a passion for developing high-impact, rapidly deployed products?Are you committed to mentoring emerging engineers and championing technical excellence?Join us in revolutionizing how insights are derived in digital marketing!Apply today!Role Summary:As a Mid / Senior Frontend Engineer at Sensor Tower, you will play a crucial role in developing top-notch products and features that enhance our user experience. Our flat organizational structure allows for your input to significantly influence product design and development.

At INGENIOUS.BUILD, we have created an exceptional platform tailored for companies within the global real estate and construction sectors. Our innovative solution allows organizations to streamline every aspect of their projects from inception to completion, facilitating collaboration both internally and externally.When you join INGENIOUS.BUILD, you embark on a remarkable journey to develop the pioneering cloud application designed to oversee the entire lifecycle of real estate construction projects. You will contribute to what many consider the pinnacle of construction project management—a bold and ambitious endeavor. If you possess the necessary skills, your contributions will be invaluable to its realization.For those with the right expertise, your involvement in this groundbreaking project will shape its future. The journey starts here...About the Role:INGENIOUS.BUILD is on the lookout for a junior Frontend Developer to join our dynamic remote team. If you bring strong programming skills, a passion for application development, and a knack for problem-solving, we want to hear from you. In this role, you will work collaboratively within a small SCRUM team, ensuring code consistency with other development teams.At INGENIOUS.BUILD, we aim to minimize meetings, allowing you to focus on your core strengths: building. We recognize the importance of flexibility and therefore offer adaptable working hours to match your productivity peaks. Our objective is to cultivate a collaborative environment that eschews unnecessary bureaucracy, empowering every team member to impact the product significantly. Our culture thrives on experienced individuals eager to engage in stimulating discussions and share insights, ensuring support and inspiration are always at hand. We encourage questioning, challenging assumptions, and cross-functional collaboration to achieve successful outcomes.Your Responsibilities:Writing and maintaining tests.Performing tasks with guidance (understanding and analyzing business requirements) using Vue.js 3 and TypeScript.Debugging issues and identifying their root causes.Committing to continuous codebase improvement, reducing legacy code, adding tests, and keeping everything up-to-date.Focus solely on development as the DevOps team handles infrastructure. Our pipelines include linting, unit, integration, and end-to-end tests, all supporting automated deployments.Learning our philosophy of writing code that is easy to test and comprehend.

Join our dynamic team at evolution as a Frontend Developer, where you will play a crucial role in designing and implementing innovative web applications. You will collaborate with cross-functional teams to deliver exceptional user experiences while utilizing the latest technologies. If you have a passion for frontend development and a desire to create impactful digital solutions, we want to hear from you!

Join Fairmarkit as a Senior Frontend Engineer and be a key player in revolutionizing the procurement process. You will design and implement user-centric web applications that elevate the user experience. Collaborate with cross-functional teams to create scalable and maintainable solutions while ensuring high performance and responsiveness.

Join Netguru, a reputable leader in digital commerce, as we partner with prominent brands to revolutionize B2B solutions, marketplaces, and retail ecosystems. Since our inception in 2008, we have empowered businesses with innovative technology, AI-driven personalization, and exceptional engineering and design expertise. Proudly certified as a B Corporation®, we are trusted by industry giants including IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted.Freelancing at Netguru:As a Netguru freelancer, you have the unique opportunity to tailor your work environment. You will determine when, where, and how you engage with projects and tasks. Our team ensures that your assignments align with your skills and interests, providing you with diverse opportunities across various industries to enhance your experience and skill set.Moreover, as a Netguru freelancer, you are not just an outsider; you become an integral part of our team with the possibility of full-time collaboration.Are you ready to make a significant impact? Come aboard Netguru, and let’s create exceptional software together.We are currently looking for a skilled Senior Golang Developer.This role is a freelance position on a B2B contract, focusing on the development and scaling of distributed systems and services. The position is 100% remote and requires the selected candidate to be available to start as soon as possible.B2B Contract | Up to 39 EUR/h | Remote | Immediate Start

At INGENIOUS.BUILD, we have crafted an exceptional platform tailored for businesses in the real estate and construction sectors globally. Our solution empowers organizations to effectively oversee every facet of their projects from inception to completion, both internally and in collaboration with other stakeholders.Joining INGENIOUS.BUILD presents an exciting opportunity to contribute to the development of the pioneering cloud application designed to manage the entire lifecycle of real estate construction projects. You will be instrumental in building what many consider the pinnacle of construction project management. This ambitious endeavor requires a bold spirit, and if you possess the right skills, you'll play a crucial role in shaping its future.If you have the necessary expertise, you'll be actively involved in its development. The journey ahead promises to be historic...About the Role:INGENIOUS.BUILD is on the lookout for a talented Mid-Level Frontend Developer to join our dynamic remote team. If you have robust programming capabilities, a deep-seated passion for application development, and a knack for problem-solving, we want to connect with you. In this position, you'll work alongside a small SCRUM team to ensure seamless system integration with other development teams.At INGENIOUS.BUILD, we prioritize minimizing meetings, allowing you to concentrate on your core expertise: development. We recognize the value of flexibility, thus offering adaptable working hours that cater to your productivity peaks. Our aim is to cultivate a collaborative workspace free from excessive bureaucracy, empowering each team member to make a meaningful impact on the product. Our culture is built on the foundations of experienced professionals who relish tackling challenging problems and sharing insights, ensuring a supportive and inspirational environment. We encourage curiosity, the questioning of assumptions, and cross-functional collaboration to drive successful outcomes.Your Contributions Will Include:Implementing robust solutions using Vue.js 3, TypeScript, and JavaScript.Optimizing and enhancing the codebase while identifying product improvements and collaborating with the team to fix bugs.Utilizing strong analytical skills and experience in developing large-scale SaaS applications such as CRM, CMS, and ERP systems.Committing to the continuous enhancement of our codebase, reducing legacy code, implementing tests, and ensuring up-to-date practices.Focusing solely on development while our DevOps team manages infrastructure, with pipelines established for linting, unit, integration, and end-to-end testing, all supporting automated deployments.Adopting our philosophy of writing code that is easy to test and reason about.

Netguru is a Certified B Corporation® that builds software for entrepreneurs and innovators. The team values trust, ownership, and transparency, working to create a safe and inclusive environment where everyone can be productive. Feedback is encouraged, and the company continually looks for ways to improve. Freelancers at Netguru set their own schedules and choose where and how they work. Assignments are matched to individual strengths, offering experience with projects from a range of industries. Freelancers can also explore full-time collaboration and become part of the wider team culture. Learn more about freelancing at Netguru: https://www.netguru.com/blog/who-are-netguru-freelancers Role overview This freelance position is for a Senior Ruby on Rails Developer. The role requires strong Ruby on Rails expertise, comfort with JavaScript, and familiarity with email delivery tools such as Mailgun or SparkPost. Requirements Extensive experience with Ruby on Rails Solid background in JavaScript Familiarity with email delivery tools (Mailgun, SparkPost, or similar) What Netguru offers Fully remote work (Poland-based, CET time zone +1/-1) Flexible hours and work locations Developer-friendly processes Potential for long-term collaboration Contract details Freelance, B2B contract Full-time assignment for 6 months

Join Valtech, a leading experience innovation company and trusted partner to some of the world's most recognized brands. We offer our team members numerous growth opportunities, a values-driven culture, and the chance to shape the future of customer experiences.The OpportunityAs a Senior Salesforce Marketing Cloud Developer at Valtech, you will engage in an environment focused on continuous learning, impactful contributions, and professional advancement. Your role will involve pioneering new digital solutions and reimagining customer experiences, ultimately driving transformation across various industries.

Join our dynamic team as a Frontend Engineer specializing in React, where you will play a pivotal role in developing and enhancing a scalable, high-performance SaaS frontend. Your focus will be on creating rich, engaging UI/UX experiences, including mobile web applications.

About Us:Planner 5D serves as a global hub for innovative home design, bringing together over 90 million users across 230 territories, including two adventurous users connecting from Antarctica each month! Our platform revolutionizes the home renovation journey from initial concept to final execution, making it easier than ever with our state-of-the-art software. You don’t need to be a professional designer to elevate your living or work space. We are passionate about making the dream of customizable homes available to everyone.Our platform is accessible across multiple devices including Web, iOS, Android, Windows, and MacOS, ensuring seamless user synchronization. Planner 5D is not just software; it's a dynamic community of dedicated and product-focused professionals. Our diverse team collaborates across different time zones, driven by a common ambition to transform the home design industry.We are on the lookout for talented individuals who are eager to take initiative and drive innovation within our expanding suite of tools. Join us in shaping the future of home design.We are seeking a Frontend Developer who shares our enthusiasm for crafting clean, maintainable, and efficient code utilizing JavaScript and TypeScript. Your primary responsibilities will involve enhancing and refactoring existing code, creating tests, and ensuring the performance and stability of our product. Our development approach primarily utilizes Object-Oriented Programming (OOP), and we adhere to stringent coding standards and technical requirements.Our technology stack includes PHP 7.4(8.1), Symfony, PHPUnit, MySQL, Redis, MongoDB, RabbitMQ, Git, Docker.For frontend, we utilize native JavaScript, jQuery (legacy code), TypeScript, and Three.js.

HelloFresh is seeking a Senior Frontend Engineer to join the Consumer Alliance team in Warszawa, Masovian Voivodeship, Poland. This position centers on developing and enhancing web applications that reach a broad customer base. What you will do Shape the user experience on HelloFresh’s platform through thoughtful frontend development. Collaborate with teammates to deliver new features and ongoing improvements. Address technical challenges and help design solutions for a diverse set of users. Share ideas and feedback in a collaborative environment. Requirements Senior-level experience in building web applications. Enjoys teamwork and values creative approaches. Comfortable tackling complex problems.