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

Vates is a French software company specializing in Open Source and virtualization with a deep commitment to open, collaborative development. Our main projects, Xen Orchestra and XCP-ng, span the full virtualization stack—from the hypervisor (Xen) and virtualization platform (XCP-ng) to management and VM backups (Xen Orchestra). Our team works across multiple countries, fully embracing remote work with transparent workflows and accessible communication channels. At Vates, we are driven by a strong, people-first culture that values benevolence, inclusivity, and a horizontal structure. Every member is empowered to contribute ideas, make decisions, and grow with the company. Our open-source model is core to everything we do, not just in our code, which is available on GitHub and GitLab, but in our collaborative approach with the community. We believe in "upstream first," dedicating our expertise and resources to support and advance foundational projects like Xen, and helping contributors of all levels join us on this journey.