Run Cloud Virtual Machines Securely and Efficiently

Cloud Hypervisor is an open source Virtual Machine Monitor (VMM) implemented in Rust that focuses on running modern, cloud workloads, with minimal hardware emulation.

Get Started

Get the source on GitHub

Secure 🔒

Minimal emulated devices and implemented in Rust to avoid many common security issues

Fast ⚡️

Boot to userspace in less than 100ms with direct kernel boot

🪟 & 🐧

Supports running modern Linux and Windows guests

Kata Containers

Supported by Kata Containers for running secure containerised workloads

Powerful REST API

Programmatically control the lifecyle of the VM using an HTTP API


Minimal memory overhead for dense deployments

Cross platform

Runs on both x86-64 and aarch64

Broad device support

Support for wide range of paravirtualised devices and physical device passthrough

Live migration

Migrate VMs from one host to another without interruption

Get Involved:

Cloud Hypervisor is governed openly as part of the Linux Foundation and supported by multiple organisations:

  • Alibaba
  • AMD
  • Ampere
  • ARM
  • ByteDance
  • Intel
  • Microsoft
  • Tencent Cloud

Join our Slack community: Invite

Participate in our community activities: Slack channel

Check out and participate in our roadmap on GitHub

For full details of our governance model please see our community repository on GitHub and our founding charter.

For bug reports please use GitHub isssues; for broader community discussions please use our mailing list

Latest news from Cloud Hypervisor project:

Cloud Hypervisor v32.0 Released!

Posted May 18, 2023 by Cloud Hypervisor Team ‐ 1 min read

This release has been tracked in our roadmap project as iteration v32.0. The following user visible changes have been made:

Increased PCI Segment Limit

The maximum number of PCI segments that can be used is now 96 (up from 16).

API Changes

  • The VmmPingResponse now includes the PID as well as the build details. (#5348)

Notable Bug Fixes

  • Ignore and warn TAP FDs sent via the HTTP request body (#5350)
  • Properly preserve and close valid FDs for TAP devices (#5373)
  • Only use KVM_ARM_VCPU_PMU_V3 if available (#5360)
  • Only touch the tty flags if it’s being used (#5343)
  • Fix seccomp filter lists for vhost-user devices (#5361)
  • The number of vCPUs is capped at the hypervisor maximum (#5357)
  • Fixes for TTY reset (#5414)
  • CPU topology fixes on MSHV (#5325)
  • Seccomp fixes for older distributions (#5397)


Many thanks to everyone who has contributed to our release:


See the GitHub Release for the release assets.