# cloud-hypervisor/cloud-hypervisor

A Virtual Machine Monitor for modern Cloud workloads. Features include CPU, memory and device hotplug, support for running Windows and Linux guests, device offload with vhost-user and a minimal compact footprint. Written in Rust with a strong focus on security.

Repository: https://github.com/cloud-hypervisor/cloud-hypervisor
Canonical: https://ross.abutalabs.com/products/cloud-hypervisor
Homepage: https://www.cloudhypervisor.org
Language: Rust
License Family: other
Topics: rust-vmm, cloud-workloads, virtualization, kvm
Last push: 2026-08-26T21:15:32+00:00

## Health v2 (maintenance only)
Score: 93/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 80, longevity 100
- inputs: {"age_days": 2682, "days_push": 7, "days_rel": 52, "gap_med": 54, "n_releases_24m": 16}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6149, forks 746 (observed 2026-08-28T04:09:36.572254+00:00)

## What it is
Cloud Hypervisor is an open source Virtual Machine Monitor (VMM) written in Rust that runs on top of KVM or Microsoft's MSHV hypervisor. It focuses on running modern cloud workloads with minimal emulation, offering CPU/memory/PCI hotplug, live migration, snapshot/restore, and a REST API for VM lifecycle control.

## Use cases
- run lightweight Linux or Windows VMs on a KVM host
- run secure containerized workloads with Kata Containers
- hot-plug CPUs, memory, and PCI devices into running VMs
- live-migrate VMs between hosts without interruption
- boot VMs in under 100ms with direct kernel boot
- run VMs with a small memory footprint for dense deployments
- control VM lifecycle programmatically via an HTTP API
- passthrough physical PCI devices to guests with VFIO

## When to choose
- you need a minimal, security-focused VMM for modern 64-bit cloud workloads
- you want fast boot times and low memory overhead for microVMs
- you need hotplug, live migration, or snapshot/restore on KVM or MSHV
- you prefer a Rust-based VMM with a small attack surface
- you run Kata Containers and need a supported hypervisor backend

## When to avoid
- you need legacy device emulation or 32-bit guest support
- you need broad architecture support beyond x86-64 and AArch64 (riscv64 is experimental)
- you want a full-featured desktop virtualization solution with GUI management
- your host kernel is too old for the required KVM functionality

## Facets
- artifact type: application
- maturity: active
- function: security, developer-tools, cloud
- domain: cloud-computing, security, infrastructure-as-code
- platform: rust, cli, cloud, self-hosted
- tags: vmm, kvm, mshv, rust-vmm, virtio, hotplug, live-migration, microvm, kata-containers, aarch64, x86-64, virtualization, containers, linux

## Member repositories
- cloud-hypervisor/cloud-hypervisor (main) score 93

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:36.572254+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:47:32.179711+00:00, confidence not recorded.
  - readme: https://github.com/cloud-hypervisor/cloud-hypervisor (fetched 2026-08-28T04:09:36.572254+00:00, sha fb79fee9dc34)
  - homepage: https://www.cloudhypervisor.org (fetched 2026-08-29T08:44:22.149639+00:00, sha 108e14761477)
  - site_page: https://www.cloudhypervisor.org/docs/prologue/introduction (fetched 2026-08-29T08:44:22.158949+00:00, sha 860f3aa1bc91)
- Data as of 2026-08-30T08:39:29.467469+00:00.