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Jobs at Open-Xchange

Interested in becoming part of something big?
You have landed in the right place. We are always looking for great talent to join our variety of departments. Check out our current job vacancies below or send us your speculative application. Become part of an exciting team at OX.

Espoo | Europe | rdmc01

Rust Developer - EU (f/m/d)

Don’t just go to work. Thrive.
We look for people who are committed to openness and have the will to revolutionize the market. You will join OX as part of a special team. As a talented individual, you can advance within your department as well as getting the opportunity to work for OX globally.

Our Vision 
A borderless internet that is open, safe and free.

We are eMail  
Worldwide companies like Comcast, Cox, 1&1, STRATO, Deutsche Telekom, Vodafone, Orange, Unitymedia, ItaliaOnline, Host Europe, NetCologne, network solutions /, Rackspace, Softbank, and GoDaddy use our "white label" products for eMail and collaboration.

Open Source is our foundation  
The mix of divergent perspectives, corporate objectives, and personal goals is our foundation and speeds up innovation.


The OX Engineering Team is looking for a Rust Developer to join our COI Messaging Initiative

COI – Chat Over IMAP – is a new emerging messaging standard based on email. With more active users than WhatsApp, Facebook Messenger and WeChat combined, email provides an excellent basis to setup a new messaging system that overcomes the chicken and egg problem of other initiatives. Learn more about COI at

With Dovecot, the world’s most popular IMAP service, OX has an excellent basis to influence future email standards in a sustainable manner. Compare

We're looking to hire a software engineer to join the OX Engineering Team, preferably in close reach to one of our office locations.

You will spearhead the development of COI and contribute to the Open Source projects Delta Chat Core and Dovecot to establish viable, federated and open alternatives to proprietary messaging solutions. As such you will work on making the client middleware Delta Chat Core compatible to the COI (Chat Over IMAP) project. You will work in close cooperation with the Dovecot IMAP as well as the client teams of OX


Your passion / Your job

  • Writing excellent quality, understandable and clean Rust code
  • Understanding Open source software – Your name will be publicly show with your commits
  • Secure coding practices
  • Writing unit tests and/or CI tests for your newly written code
  • Designing and developing new features
  • Debugging bugs, crashes and performance problems. Sometimes this requires understanding external software (or even hardware), such as the (mobile) OS, storage system, load balancer, firewall, etc.
  • Writing performance critical code.
  • Ideally have experience in Rust development


What you bring to the table

  • Bachelor’s degree in Computer science or corresponding work experience
  • Good Rust skills, as future parts of Delat Chat Core will be implemented in Rust
  • Good debugging skills to understand and fix crashes and other strange behaviour (gdb, valgrind, strace)
  • Experience with C on mobile OS (NDK on Android, iOS)
  • Determining operational feasibility by evaluating requirements, analysis, solution development, and proposed solutions
  • Ability to work independently with support the of the OX team
  • Goal-oriented working style and high self-motivation
  • Team player and ability to communicate well amongst peers


What we offer

  • Working on modern software in an international team
  • Wide scope to develop your own ideas and projects
  • Possibility occasionally to work from home and the opportunity to work from one of our well-appointed worldwide offices
  • The most current and jazzy equipment
  • Continuous personal development & training
  • Flat hierarchies combined with an "Open Door" policy
  • Great fringe benefits

About Open-Xchange

Open-Xchange (OX) is a market leader in Mail / Messaging and DNS-based security services, with more than 200m seats sold through international hosting and telco providers worldwide, including partners such as 1&1, Orange, Italiaonline, Comcast, GoDaddy or Softbank.

We at OX have our roots in Open Source, and this has shaped our view of the world and culture – open, diverse, and with a bias to act, giving everyone at OX room to take responsibility within their team and grow. OX believes in an internet that is open, safe and free. We want to create competitive products that allow our providers to deliver secure internet services with a great user experience, and that respect privacy and generate value.

With some 270+ people worldwide, OX develops and operates Open Source software (aaS) for mail / messaging (OX App SuiteOX Guard) and collaboration / productivity (OX DriveOX Documents). OX’s  Dovecot is the world’s dominant open-source IMAP server software, and our PowerDNS provides secure DNS services to our telco customers and their users.

Our business is fast-paced and changing constantly. We are looking for people who share our beliefs, who are out there to make a difference, are entrepreneurial and enjoy working in a high-tech environment as part of a truly international team. OX is headquartered in Cologne, with further locations throughout Germany (Hamburg, Bremen, Dortmund, Olpe and Nuremberg), the USA (Louisville, KY), Finland, the Netherlands, Italy, France, Spain and Japan (Tokyo).

If you are interested, please contact Jochen F. Schude for further information - or send us your paperless application with a cover letter including the job ID (see at the top left corner), tabular CV, certificates, salary expectations and the earliest possible date of entry by e-mail to recruiting at