API/XAPI Developer


Job description

Type of contract / Length

Full time (permanent contract)


Full remote, hybrid or on site (Grenoble, France)


The XCP-ng team develops and maintains a powerful Open Source API called "XAPI", hosted within the Linux Foundation/Xen Project. It is responsible for exposing all the features of XCP-ng to various API consumers, including Xen Orchestra, without requiring any manual modification or SSH access to do advanced operations (like network, storage and VM creation, among many other things). This is a unique opportunity to work as a central layers at the frontier of lower level layers (Xen) and higher level ones (Xen Orchestra). Vates is looking for a developer with some OCaml knowledge (or similar, like Haskell, F#, SML, Reason ML…) or willing to develop OCaml skills. As part of the XCP-ng team, you'll have the chance to generate a significant impact on our systems running on thousands of machines all around the world. If you want to participate to a real OCaml production use case, you will enjoy this opportunity:
  • You'll work in a team with a "full stack" knowledge (from the Xen Hypervisor to the management central console in NodeJS, "Xen Orchestra", consuming this API. Therefore, you'll be an essential layer between lower and higher layers.
  • You'll implement new features in the API, exposing Xen or network capabilities to be used then by Xen Orchestra
  • You'll also work on the improvement of the toolstack: optimizations, some rewrite
  • If you are also a Rust language fan, it's possible we'll add or replace some parts in Rust!


  • BS in Computer Science or related discipline, or equivalent work experience
  • Some experience on OCaml language or similar
  • Good capacity to understand the requirements from both lower and higher layers (between Xen Hypervisor and Xen Orchestra)
  • Team player

Our Company

Vates is a French software developer specialized in Open Source and virtualization. Xen Orchestra and XCP-ng are its two main projects. With 2 main product teams, we are covering the whole stack, from the hypervisor (Xen), the virtualization platform (XCP-ng) to management and VM backups (Xen Orchestra). Our current teams are based in multiple countries, with a 100% "remote work enabled" workflow. Every bit of code is available publicly on Github or Gitlab. Our team is doing Open Source as its core, since our entire company is developing every product in a full open fashion: from the code, but also the way we work with the community, helping people to contribute and providing our experience and resources to upstream projects, like Xen. "Upstream first" is our de facto standard.

Are you the one?

  • Step 1

    Send your application with your resume and explain us in your email what motivates you to join us
  • Step 2

    Meet your potential manager and co-workers at the office or remote in order to check if it’s a good fit for both you and us
  • Step 3

    Receive your offer and start working for us!
We respond to everyone.

Learn more about Vates

Vates was born more than 10 years ago in the French Alps, in Grenoble. Our team is composed of more than 20 people, spread out in France and elsewhere in the world. Want to know more about our history? Our team? Thinking of joining us?

About Vates