Rust VMM

A shared ecosystem of Rust crates — KVM bindings, memory management, virtio device models — that any VMM project can build on. It's the reason a handful of competing companies all ship good microVM monitors: they reuse the same battle-tested foundation instead of reinventing it. Source: emirb.github.io/blog/microvm-2026, 2026-06-21

What it is

After AWS open-sourced Firecracker (a Cloud Hypervisor sibling effort followed), every new VMM kept reinventing the same low-level components: KVM wrappers, virtio device models, memory management. AWS, Intel, Google, Microsoft, Red Hat, Alibaba, Linaro, and others recognized the waste and started collaborating on rust-vmm, a shared set of Rust crates. Source: emirb.github.io/blog/microvm-2026, 2026-06-21

The crate ecosystem as of 2026 (per the FOSDEM 2026 talk by Stefano Garzarella, Ruoqing He, and Patrick Roy):

  • Core VM: kvm-ioctls, kvm-bindings, mshv-ioctls (Hyper-V), xen-ioctls (Xen), linux-loader
  • Resource management: vm-allocator, vm-memory (IOMMU support, guest_memfd, Kani formal verification)
  • Device emulation & I/O: virtio-queue, virtio-bindings, vhost, vhost-user-backend, vfio-ioctls, vm-superio
  • vhost-user devices: can, console, gpio, gpu, i2c, input, rng, scmi, scsi, sound, spi, video, vsock, virtiofsd

Source: emirb.github.io/blog/microvm-2026, 2026-06-21

Why it's "the real revolution"

The survey's central claim is that rust-vmm — not any single VMM — is the breakthrough. It means the industry doesn't have one good VMM; it has a shared foundation that makes many good VMMs possible, each optimized for different trade-offs. An improvement to vm-memory benefits Firecracker, Cloud Hypervisor, libkrun, Dragonball, and crosvm at once. A new architecture (RISC-V) implemented once in the crates is inherited by every consumer. Source: emirb.github.io/blog/microvm-2026, 2026-06-21

Consumers span the industry: Firecracker (AWS), Cloud Hypervisor (Intel/Microsoft), crosvm (Google/ChromeOS), libkrun (Red Hat), Dragonball Sandbox (Alibaba/Kata), OpenVMM (Microsoft), and virtiofsd (the reference virtio-fs daemon). This breadth is why building a new sandbox platform takes weeks, not years — the hard problems are already solved in the crates. Source: emirb.github.io/blog/microvm-2026, 2026-06-21

Current direction (2026)

Announced at FOSDEM 2026: consolidation into a monorepo (the kvm, vfio, vm-virtio, and vhost workspaces are already merged) plus RISC-V architecture support and POSIX/*BSD portability. Formal verification via Kani proofs is being applied to memory-management crates. Source: emirb.github.io/blog/microvm-2026, 2026-06-21

Relevance to Kevin

The shared substrate beneath Dedalus's VMM (DHV, a Cloud Hypervisor fork). Improvements to rust-vmm crates flow into the Dedalus stack for free, and the convergence on KVM + shared crates is part of why the agent-infra sandbox market commoditized so fast — the moat is what you wrap around the VM, not the VM itself. See Containers Are Not a Security Boundary and MicroVM and Sandbox Isolation Architecture.


Timeline

  • 2026-06-21 | Page created from emirb's "Your Container Is Not a Sandbox" survey (citing FOSDEM 2026). Captured the crate inventory, the cross-company consumer list, the monorepo + RISC-V + Kani direction, and the "shared foundation, not a single VMM" thesis. Source: emirb.github.io/blog/microvm-2026, 2026-06-21