Full-Stack Developer (m/f/d) – Backend Focus

Join Anyone AI as a talented Full-Stack Developer and collaborate on groundbreaking projects with a premier AI laboratory.Qualifications:Fluent in professional written English3 to 7 years of hands-on experience in software engineeringExpertise in Python and JavaScript/TypeScript, with familiarity in Java, C#, or GoExperience in backend or full-stack development within production environmentsFamiliarity with testing frameworks such as pytest, Jest, JUnit, xUnit, and Go testingProven track record of debugging and navigating extensive codebasesExperience in code reviews, refactoring, and production migrationsEngagement: This is a part-time, project-based consultancy role.Work Type: RemoteAs a contributor, you will design and evaluate authentic software engineering tasks, focusing on bug fixing, feature development, refactoring, and test generation. Your role involves crafting intricate coding scenarios and assessing peer submissions for quality and precision.Responsibilities:Create and implement multi-file coding tasks for bug fixes, feature enhancements, refactoring, and testingProduce clear, natural-language specifications and reference implementationsExpand and maintain unit and integration test suitesReview tasks generated by peers for correctness, clarity, and realismIdentify edge cases, ambiguities, and potential failure scenariosEnsure that specifications, code, and expected outputs are alignedExpected Outcomes:Deliver high-quality, production-ready coding tasks

Role Overview anyone-ai is seeking a Backend Developer focused on AI training. This position centers on building and maintaining backend systems that power advanced AI technologies. The work supports the development and refinement of machine learning models. What You Will Do Develop backend systems that enable AI research and model training Work closely with the AI research team to improve machine learning models Help enhance and maintain training datasets for quality and reliability Location This role is based in Germany.

Anyone AI is seeking Backend Developers to join project-based consulting work with a prominent AI research lab. This remote, part-time role centers on designing and evaluating realistic software engineering tasks for AI training, with a focus on backend systems. Role overview As a Backend Developer – AI Trainer, the position involves crafting and reviewing coding scenarios that mirror real-world engineering challenges. Typical tasks include bug resolution, feature implementation, refactoring, and test creation. The work will also require reviewing peer submissions to ensure they meet quality standards. What you will do Create and implement multi-file coding tasks, including bug fixes, new features, refactoring, and test generation. Draft clear, natural language specifications and provide reference implementations. Develop and expand unit and integration test suites. Review peer-generated tasks for accuracy, clarity, and feasibility. Identify edge cases, ambiguities, and potential failure points. Ensure specifications, code, and outputs remain consistent and aligned. Requirements Professional fluency in written English and strong communication skills. 3 to 7 years of hands-on experience in software engineering. Advanced knowledge of Python and JavaScript or TypeScript, plus working familiarity with Java, C#, or Go. Experience in backend or full-stack development in production environments. Proficiency with testing frameworks such as pytest, Jest, JUnit, xUnit, or Go testing tools. Ability to debug and work within large, multi-file codebases. Comfort with code reviews, refactoring, and production migrations. Engagement details Part-time, project-based consulting Remote work Location: Germany Expected outcomes Deliver high-quality, production-ready outputs for AI training and evaluation.

About the Role We are seeking a Senior Full-Stack Engineer who excels at the convergence of product innovation, infrastructure development, and AI-enhanced programming. In this pivotal role, you'll design and implement scalable web applications that will contribute directly to the technical architecture of Bluefish’s cutting-edge AI marketing platform. You will collaborate closely with AI engineers, product managers, and designers to develop impactful features, ensuring that our solutions are technically robust and aligned with user requirements. We are looking for a candidate with a strong focus on product outcomes, who values user experience as much as implementation. As a vital team player, you will foster a culture centered on ownership, high engineering standards, and ongoing improvement. You will mentor colleagues, engage in thoughtful design discussions, and help the team to achieve rapid progress without compromising quality. This position provides the chance to take ownership of critical systems, influence our technical strategy, and help shape the future of AI-assisted development in marketing technology. This position is fully remote within Germany. What You Will Do Architect and develop scalable, secure web applications, making thoughtful decisions between speed, reliability, and complexity. Align design with engineering by validating the technical feasibility of UI/UX designs and optimizing performance from the initial render to database queries. Establish and maintain high engineering standards through rigorous code reviews, coding best practices, and specification-driven development that keeps the team aligned and agile. Lead initiatives to scale systems to accommodate a 100x increase in load, identifying bottlenecks and fortifying infrastructure proactively. Collaborate closely with AI engineers, product managers, and designers to create technically sound and impactful solutions. Stay informed on advancements in GenAI, LLMs, GEO, and AI-driven marketing, converting emerging trends into actionable product and technical strategies.

jobgether is looking for a Senior Full Stack Engineer based in Germany. This position centers on building and maintaining applications that support both the front end and back end of our platform. Role overview The Senior Full Stack Engineer will work with multiple teams to design, implement, and support scalable solutions. The focus is on improving user experience and strengthening product functionality. Day-to-day, this means developing features, solving technical challenges, and ensuring our applications run smoothly. Collaboration Expect close collaboration with colleagues from various disciplines. Input and ideas will help shape product direction and service quality. Contributions in this role play a key part in the company’s growth and the ongoing improvement of our offerings.

About the PositionJoin our dynamic team as a Staff Full-Stack Engineer where your expertise will play a pivotal role at the intersection of product development, infrastructure, and AI-powered solutions. In this influential position, you will spearhead the architecture and continuous improvement of scalable web applications, contributing significantly to the foundation of Bluefish's AI marketing platform.Your collaboration will span multiple teams, working closely with AI engineers, product managers, designers, and infrastructure specialists to convert abstract product concepts into robust and scalable systems. Beyond just feature development, you will define architectural patterns, steer technical direction, and make certain that engineering decisions align with our company’s growth trajectory.We seek an individual with a strong focus on product and system thinking, dedicated to delivering sustainable solutions and creating measurable impacts for our customers.As a technical leader within our engineering division, you will enhance engineering practices across teams by leading design reviews, mentoring senior engineers, and establishing standards that facilitate rapid progress while ensuring reliability and quality.This role provides the chance to shape the architecture of core systems, influence the overall technical strategy of the company, and define how AI-assisted development will drive the future of marketing technology.Note: This role is primarily associated with our office in Berlin, but we offer remote work options within Germany.

Join Alten as a Full-Stack Java Developer and contribute to innovative projects in a dynamic environment. As part of our team in Munich, you will engage in designing, developing, and implementing software solutions that meet our clients' needs. This role offers an exciting opportunity to work with cutting-edge technologies, collaborate with talented professionals, and drive change in the tech landscape.

Anyone AI is seeking experienced software engineers in Germany for a part-time, project-based role supporting a leading AI research lab. This position centers on expert evaluation and allows for fully remote work within Germany. Key responsibilities Design and complete multi-file coding tasks, such as bug fixes, new features, refactoring, and testing Write detailed specifications in natural language and supply reference implementations Develop and enhance unit and integration test suites Review tasks created by peers for accuracy, clarity, and realism Identify edge cases, ambiguities, and potential failure points Verify alignment between specifications, code, and expected outcomes Requirements Exceptional written English 3–7 years of professional software engineering experience Strong skills in Python and JavaScript or TypeScript; familiarity with Java, C#, or Go is a plus Experience in backend or full-stack development for production systems Comfort with testing frameworks like pytest, Jest, JUnit, xUnit, or Go testing tools Advanced debugging abilities in large, multi-file codebases Background in code reviews, refactoring, and handling production migrations What success looks like Consistently delivers production-ready code and thorough documentation Work arrangement Part-time, project-based contract Remote within Germany

Join our dynamic team at CHECK24 as a Full-Stack Developer with a focus on backend technologies. You will be responsible for developing innovative solutions that enhance our digital platforms and services. Collaborate with cross-functional teams to drive projects from concept to completion, ensuring high performance and responsiveness of applications.

About The RoleAt think-cell, we are dedicated to revolutionizing the way professionals create impactful business presentations. By integrating advanced automation and assistance features, we enhance our product to serve over 1.3 million users globally. In this exciting role, you will transform innovative ideas and cutting-edge AI concepts into robust features that redefine user experience.Your responsibilities will include developing production-ready systems that seamlessly connect modern backend services with user-friendly interfaces. Collaborating closely with C++ engineers on our core product and AI engineers pushing the boundaries of automation, you will play a pivotal role in bringing new functionalities from concept to everyday use.This position is perfect for engineers who take pride in crafting clean, scalable systems, prioritize code quality, and thrive in a collaborative environment where impactful features are regularly delivered.

jobgether is looking for a Full-Stack Product Engineer based in Germany. This position covers both front-end and back-end development, supporting the creation of applications that improve user experience. Role overview This role involves contributing to the entire development process, from designing features to building and maintaining applications. The work spans multiple projects and offers the chance to apply a broad range of technical skills. What you will do Develop and maintain both front-end and back-end components of web applications Collaborate with team members to deliver features that support user needs Work on projects aimed at improving performance and usability Requirements Experience in full-stack development Ability to work on both user-facing and server-side features Interest in building high-performance, user-focused applications

Join our dynamic team at CHECK24 as a Full-Stack Developer (m/f/d) focused on AI and Digital Innovation. In this role, you will be at the forefront of developing cutting-edge applications that drive our digital transformation efforts. You will collaborate closely with cross-functional teams to create user-friendly and efficient solutions that enhance customer experiences.

Role Overview check24 is looking for a Full-Stack Developer (m/w/d) to help shape AI and digital innovation projects. This position sits within the App & Web Full Stack team in Erfurt. The work centers on building and improving applications that make user experiences smoother and support efficient business operations.

haufegroup seeks a Senior Full Stack Developer (Java) to help build and maintain scalable web applications in Freiburg im Breisgau. This role involves working closely with colleagues from various backgrounds to deliver dependable software solutions. Key responsibilities Develop and support web applications, using Java as a primary technology Work with cross-functional teams throughout the software development lifecycle Help ensure delivered solutions are high-quality and easy to maintain Location This position is based in Freiburg im Breisgau.

Join CHECK24 as a Junior Full-Stack Developer (m/f/d) where you will play a crucial role in shaping AI and digital innovations. In this exciting position, you will collaborate with our talented team to design, develop, and enhance our applications and web platforms, ensuring a seamless user experience.

At TechBiz Global, we pride ourselves on being more than just a recruitment and software development agency; we are a dedicated German-based global partner focused on driving your business success. Our diverse and distributed team specializes in IT recruitment, outstaffing, outsourcing, software development, and consulting services, catering to over 100 clients across more than 20 countries. We are currently in search of a Senior Full Stack Developer to join one of our esteemed client's teams. If you are looking for an exhilarating opportunity to advance your career in an innovative environment, this role may be the perfect match for you.

Are you an accomplished business development professional eager to apply your expertise in the rapidly evolving field of Artificial Intelligence? If you can dedicate between 8 to 20 hours per week while managing your current commitments, we want to hear from you!At 10x.team, we specialize in connecting fractional and freelance experts with leading AI laboratories to elevate the quality of advanced AI systems.Your Role: As a Business Development Manager with a focus on AI training, your impact will be significant. You will:Refine AI-generated responses concerning business development, commercial strategy, and client relations.Assess outputs for business logic, market relevance, and practical application.Craft realistic business scenarios across various industries, including market entry strategies, partnership development, and sales processes.Analyze AI reasoning in deal qualification, client needs analysis, value proposition articulation, and closing strategies.Identify gaps or misinterpretations in market approaches, sales methodologies, or strategic recommendations.Create scenario variations from different stakeholder perspectives, such as business development manager, client decision-maker, or commercial partner.In essence, your role will involve assessing and enhancing AI-generated content to align with real-world business development practices, ensuring that our AI systems have a meaningful impact in commercial and strategic settings.

Join our dynamic team at dreessommerse as a (Senior) Full-Stack Developer specializing in web technologies. We are seeking an innovative and experienced individual who is passionate about coding and web development. In this role, you will work on exciting projects that challenge your skills and expand your knowledge in a fast-paced environment.

jobgether is looking for a Senior Full-Stack Engineer based in Germany with strong experience in Python and React. This role centers on building and improving software that supports the company’s platform. Role overview This position involves developing features from initial idea through to deployment. Collaboration with colleagues from different teams is a key part of the job, with a shared focus on delivering reliable code and a smooth user experience. What you will do Work with Python and React to create and maintain platform features Contribute to project planning, development, and release Collaborate with cross-functional teams to meet project goals Help ensure code quality and a positive experience for users