Infomaniak Public Cloud is an infrastructure-as-a-service platform built on OpenStack. It offers virtual machines (including GPU instances), block storage on Ceph, object storage with an S3-compatible API, networking with load balancers, managed Kubernetes and managed databases such as MariaDB, MySQL, PostgreSQL and Redis. You use the services yourself through the console and OpenStack-compatible APIs. According to Infomaniak, the platform was developed in-house, and the company's own services, such as kDrive and Swiss Backup, run on it too.
Infomaniak is headquartered in Switzerland and says it develops and operates the service exclusively there, in its own data centres, which hold certifications including ISO 27001. Switzerland is not an EU member state but belongs to EFTA, so your data is hosted outside the EU. Because the platform rests on open OpenStack interfaces, workloads can in principle move to other OpenStack providers. The service itself is not open source, although the underlying technology is.