Firecracker is a virtual machine monitor designed to run lightweight, isolated workloads using hardware-assisted virtualization. Developed originally by Amazon Web Services, it targets serverless computing, container isolation and environments where large numbers of short-lived virtual machines must be started efficiently.
The software uses Linux KVM to provide isolation while maintaining a deliberately small virtual hardware model. By excluding unnecessary devices and guest-facing functionality, Firecracker reduces the memory footprint and attack surface of individual virtual machines, known as microVMs.
Unlike general-purpose virtualization platforms, Firecracker does not provide a conventional graphical management interface. Instead, each virtual machine monitor process exposes an API through which software can configure and control microVMs. This design makes it particularly suitable for orchestration systems and automated infrastructure.
Security is central to the architecture. Firecracker combines hardware virtualization with restricted system calls, process isolation and resource controls. The accompanying Jailer utility provides additional isolation by configuring namespaces, control groups and reduced process privileges before starting a virtual machine.
This is free and open source software.
Key Features
- Create and run lightweight microVMs using Linux KVM.
- Minimal virtual hardware model designed to reduce attack surface and resource consumption.
- API for configuring and controlling microVM execution.
- Configure virtual CPU counts, memory allocation and CPU templates.
- Start guests using specified kernel images, root filesystems and boot arguments.
- Attach file-backed block devices with read-only or read-write access.
- Configure virtual network interfaces for isolated workloads.
- Apply bandwidth and operation-rate limits to supported virtio devices.
- Rescan block devices and modify their backing files.
- Support virtio-vsock communication between guests and the host.
- Provide virtual entropy and persistent memory devices.
- Configure memory hotplugging for supported workloads.
- Snapshot and restore microVM execution state.
- Export operational metrics and diagnostic logs.
- Provide a guest-facing metadata service.
- Advanced thread-specific seccomp filters to restrict system calls.
- Jailer utility for namespace isolation, control groups and privilege reduction.
- Support CPU oversubscription and demand fault paging.
Website: github.com/firecracker-microvm/firecracker
Support:
Developer: Amazon Web Services and contributors
License: Apache License 2.0
Firecracker is written in Rust. Learn Rust with our recommended free books and free tutorials. Learn Python with our recommended free books and free tutorials.
Related Software
| Hypervisors | |
|---|---|
| Proxmox | Virtualization management platform |
| Xen Hypervisor | Fastest and most secure infrastructure virtualization solution |
| KVM | Full virtualization solution for x86 hardware |
| oVirt | Virtualization solution for your entire enterprise |
| Firecracker | Create and run lightweight microVMs |
| XCP-ng | High performance enterprise level virtualization platform |
| Lguest | Little hypervisor designed for experimentation with virtualization |
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