MTA & Anti-Abuse Engineer (m/f/d)

Our mission: Are you a motivated and experienced engineer who wants to make an impact by developing and operating scalable MTA platforms while designing systems to detect, prevent, and mitigate abuse?At Open-Xchange (OX), we develop open-source communication and collaboration software used by public sector organizations, telcos, and hosting providers to keep data secure and under their control. Our products cover email, collaboration, DNS security, and related services, and are used by millions of people worldwide. Discover what OX offers you: We work in a non-hierarchical organization that empowers everyone to take responsibility, stay focused, and contribute directly to the company’s success and customer value. We value expertise and continuous professional development. Our professionals work closely with experienced colleagues, take ownership of their work, and continuously expand their skills. Openness and diversity are core to OX. Different perspectives, backgrounds, and ways of thinking strengthen our collaboration and help us see the bigger picture. Your team: You'll join our engineering team focused on developing and maintaining the OX Cloud MTA platform and Anti-Abuse systems. Working within a large-scale operational environment, you’ll contribute to the implementation of architectural decisions and apply your expertise to ensure the platform’s reliability, stability, and security. Your work will focus on improving the platform through continuous technical enhancements, while ensuring uninterrupted mail delivery performance. Your new job: Contribution to the development and maintenance of the OX Cloud MTA platform and Anti-Abuse tooling, working on code and policies to ensure high performance and reliability. Design and continuous improvement of technical processes to detect, prevent, and respond to abuse across the OX Cloud platforms, with a strong focus on detection and mitigation systems. Optimization of workload efficiency through automation of routine tasks and enhancement of monitoring tools and processes. Cross-functional collaboration to support product delivery, contribute to the overall direction of OX Cloud through participation in leadership committees, and ensure alignment with team objectives and priority projects. Development and sharing of expertise in abuse analysis, investigation techniques, and relevant tools within the team, including mentoring junior team members in both technical topics and their professional development. Development of internal components as well as responsibility for deploying and maintaining them at scale. Preparation, review, and maintenance of Statements of Work (SOWs), contracts, and other technical and legal documentation in collaboration with relevant stakeholders. This is the tech stack you'll be working with: Operating system: Linux Protocols and standards: SMTP, SPF, DKIM, DMARC Containerization, orchestration, and infrastructure management: Kubernetes, OpenStack, Terraform, Ansible Programming languages: Golang, Python Your background: Several years of hands-on experience as an Anti-Abuse Engineer or Software Engineer. Experience with distributed architectures, ideally in Kubernetes-based environments. Familiarity with the MTA and AVAS vendor landscape, combined with a strong interest in automation across delivery monitoring and abuse handling. Analytical mindset with enjoyment in solving complex security and deliverability challenges. Continuous drive to improve abuse detection and prevention approaches, including testing and refining solutions. Interest in evolving standards and willingness to work with RFCs when needed. Strong verbal and written communication skills in English. Intrinsic motivation to take ownership and a passion for open-source technologies, thriving in a low-hierarchy environment. Comfortable working in a remote-first environment with multicultural teams across different time zones. For US-based applicants: Applicants must be legally authorized to work in the United States. The company is not able to provide employment visa sponsorship at this time. This is what you get at OX: The flexibility to work 100% remotely ensures a work environment that suits you best. Flexible working hours that allow you to successfully combine your home and family responsibilities with work. Getting together in-person for workshops and fun team events. Time off to volunteer – and mental health support when you need it. We provide financial relief through corporate benefits and a subsidy for ergonomic chairs and desks. We can discuss further location-related benefits together in an initial talk. Join the team: Join us in our fight for an open internet and deliver added value! Click “Apply now” to submit your application. Your contact person: Reach out to Justin ([email protected]) from the People Team. He will be able to discuss current opportunities and tell you more about our exciting vision and mission @OX.