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

Our Mission:

Are you a motivated experienced person, used to working in an international multi-cultural environment, who really wants to make a difference in the open-source world? 

At Open-Xchange, we decided to leave dead-end jobs where you don't make an impact and offer passionate experts the opportunity to be part of an agile, international team that connects the world and millions of people by developing and delivering open-source technologies.  

We believe it’s crucial to work in an environment where people feel valued, are energized by their work and deliver added value – not only to colleagues, but also to everyone using our products.

Discover what Open-Xchange offers you:

• Our non-hierarchical organization not only ensures much better value creation for our customers, it also provides the best possible work environment for every one of us.

• We believe that everyone at OX will always do what is best for the company. We believe that the full potential for high performance can only be realized within an organizational structure that enables each individual to work with clear focus and to take full responsibility for their tasks.

• At OX we focus a lot on mastery. It influences our decision-making processes and is a great part of how we look at professional development.

• We believe in openness and diversity, which are crucial to OX’s success. Different opinions, ways of thinking, and cultures enrich us and help us to better understand the bigger picture.

• At OX you'll be working with the whole tech stack, using open source technology, and playing your part in the fight against big, dominant companies to keep the Internet open.

Team info:

You'll join our engineering team focused on developing and maintaining the OX Cloud MTA platform. 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:

• You'll contribute to the development and maintenance of the OX Cloud MTA solution, working on the codebase and policies alongside your team to ensure high performance and reliability.
• You'll design and improve technical processes to detect, prevent, and respond to abuse across the OX Cloud Platforms — with a strong focus on refining our detection and mitigation systems.
• You'll help increase workload efficiency by automating routine tasks and improving monitoring tools and processes.
• You'll work cross-functionally to support product delivery, ensuring alignment with team objectives and priority projects.
• You'll handle the IP warm-up and RBL delisting processes to help maintain optimal email deliverability.
• You'll develop and share your expertise in abuse analysis, investigation techniques, and relevant tools with the rest of the team.

This is the tech stack you'll be working with:

• Common protocols/standards SMTP, SPF, DKIM, DMARC, DANE
• Our server deployment, configuration, and management use OpenStack, Kubernetes, Chef, Terraform and Ansible
• Coding languages include Golang, Python or Ruby
• Our operating system is Linux

Your background:

• You have hands-on experience as a delivery engineer, anti-abuse engineer, or systems engineer, ideally with a focus on security and reliability.
• You're familiar with the MTA and AVAS vendor landscape and like to automate wherever it makes sense — whether it’s delivery monitoring or handling abuse cases.
• You enjoy digging into tricky issues and figuring out solutions to complex security or deliverability problems.
• You're always looking for better ways to detect and stop abuse, and you’re comfortable testing and refining your approach.
• You keep up with evolving standards and don’t mind diving into an RFC when needed.
• You can effectively communicate in English verbally and in writing across all levels.
• You would like to work in an environment without a formal hierarchy and are ready to take ownership for your work.

This is what you get at Open-Xchange:

• The flexibility to work 100% remotely or in one of our offices ensures a work environment that suits you best.
• Flexible working hours that allow you to successfully combine your home and family responsibilities with work. 
• Stay up to date with latest tech, by working on modern cloud software in a dynamic, international team.
• Sharing thoughts is part of our DNA so expect Workshops and Team Events.
• Benefit from time off for volunteer work.
• We can discuss further location-related benefits together in an initial talk. 

Join the team:

Be ready to shape your personal future, and the future of millions of people. 

Join us in our fight for an open internet and deliver added value! All you need to do is get in touch, so click the ‘apply now’ button, fill the form and be in contact. 

Your contact person:

Reach out to Justin (recruiting@open-xchange.com) from the People Team. He will be able to discuss current opportunities and tell you more about our exciting vision and mission @OX.