freelance English-speaking jobs in Bielefeld

The General Manager, Europe will lead the company's expansion across the region, developing and executing growth strategy, establishing regional operations, and building partnerships.

Software Architect responsible for solution and integration architecture, technology selection, and support of development teams. Designs architecture roadmap, develops documentation, and leads software development projects. Requires deep knowledge of software development practices, web and cloud technologies, and microservice architecture.

Project Support Employee needed to assist in the coordination and execution of project activities. Support cross-functional teams, ensure communication with Greek-speaking stakeholders, and contribute to project goal achievement. Native Greek and strong German language skills required. Experience with ERP systems and MS Office is beneficial.

The Leibniz Institute for Natural Product Research and Infection Biology seeks a Scientific Communication, Public Relations, and Events Officer to prepare and communicate research results and activities, particularly for the INCATE project. Responsibilities include writing accessible texts, supporting public relations activities, organizing events, and developing communication materials. The ideal candidate has a degree in media, communication, journalism, or public relations, or a natural science degree with proven science communication skills. Fluency in German and English is required.

PhD position in deep learning for phase-contrast synchrotron X-ray tomography. Develop physics-informed, self-supervised learning approaches for phase retrieval and implement reconstruction algorithms for large-scale hierarchical tomography.

IT Specialist will provide IT support, monitor systems, administer servers and software, manage user accounts, and participate in IT projects. Requires a Bachelor's degree in computer science, several years of IT support experience, knowledge of hardware and software, and excellent communication skills. German language proficiency is required.

Lead DevOps Engineer to design, own, and scale the multi-cloud backbone of IQA, an AI-powered SaaS solution. Define and execute the multi-cloud infrastructure roadmap, own the technical strategy for Kubernetes-based deployment infrastructure, and build, deploy, and monitor deployments across various cloud providers and on-premise setups. Engineer DevOps tooling and automation layers, own the infrastructure strategy including data, CI/CD, and orchestration, and develop and optimize APIs and data processing systems using Python. Collaborate with product and engineering leadership to translate business requirements into robust infrastructure capabilities.

Support Engineer (all genders) for network and IT solutions. Analyze and resolve network and security incidents remotely. Provide 2nd & 3rd level support, including on-call duty. Document cases and infrastructure. Must have experience in the service provider, data center, or integrator environment and fluency in German and English.

Define system, data, and deployment architectures for AI solutions. Establish standards and patterns while architecting LLM/ML solutions with rigorous evaluation and safety. Design MLOps foundations for reproducibility and engineer for reliability, latency, cost efficiency, observability, and resilience.

Senior Principal Software Engineer will lead Zalando's migration to React Native, solving complex engineering challenges and ensuring a scalable, secure transition. You will champion a performance-first culture, mentor engineers, and architect core app features with performance as a primary consideration. Extensive experience developing large-scale React Native applications and deep architectural fluency in the new React Native architecture are required.

Lead and scale the Battery Control System (BCS) Product Team, developing reliable, high-performance systems for energy storage. Guide a cross-functional team of firmware, hardware, and testing experts. Foster a culture of clear ownership, pragmatic execution, and strong technical standards.

Senior Backend Developer will design, implement, and maintain scalable backend systems. Responsibilities include API design, LLM integrations, and collaborating with frontend teams. Requires several years of experience as a Backend Developer with strong proficiency in Kotlin, Java, or a JVM-based language.

Senior Protection & Secondary Design Engineer specializing in Medium Voltage (MV) systems. Designs protection schemes, develops secondary schematics, selects relays, and configures, tests, and commissions protection systems. Requires 7-10+ years of experience in protection engineering and secondary system design (MV level).

PhD student will use MINFLUX microscopy to track proteins during translocation into mitochondria. Tasks include establishing labeling techniques, isolating proteins, and contributing to publications.

Software Architect needed to design, develop, and implement software solutions. Responsibilities include defining technical vision, ensuring software quality and scalability, and providing technical leadership to development teams. Requires a Bachelor's or Master's degree in Computer Science or a related field and 5-7 years of experience as a Software Architect.

The German Federal Pension Insurance seeks IT Security Consultants to support and advise on the operational implementation of IT security requirements. Responsibilities include contributing to the creation and development of IT security concepts, managing technical support for acceptance testing, advising business units and IT operations, and identifying vulnerabilities.

Senior Data Scientist to co-lead data team, building and improving data pipelines for a web-based geospatial information system. Manage a data catalogue of over 2,000 datasets and collaborate with data scientists, engineers, and the renewable energy market.

Manages standard and moderately complex payroll implementations, ensuring projects are delivered on time and to a high standard. Prepares project documentation, identifies risks, and collaborates with cross-functional teams. Supports seamless handovers to Payroll Support and mentors less experienced team members.

Lead a team of IT experts in the "Platform Operations Center" ensuring smooth client IT infrastructure operations. Manage projects, develop IT solutions, and advise clients on technical matters.

Senior Requirements Engineer translates business initiatives into detailed technical requirements and acceptance criteria. You will work closely with Product Management, QA, and Engineering to ensure clarity and minimize friction throughout the feature lifecycle. Experience in Requirements Engineering, IT Business Analysis, or a similar role is required, along with strong analytical and communication skills.