Is Amazon's Firecracker just reinventing the LXD wheel?

From their github page

Firecracker is a new virtualization technology that enables customers to deploy lightweight micro Virtual Machines or microVMs. Firecracker microVMs combine the security and workload isolation properties of traditional VMs with the speed, agility and resource efficiency enabled by containers. They provide a secure, trusted environment for multitenant services, while maintaining minimal overhead.


  • Firecracker can safely run workloads from different customers on the same machine.
  • Customers can create microVMs with any combination of vCPU and memory to match their application requirements.
  • Firecracker microVMs can oversubscribe host CPU and memory. The degree of oversubscription is controlled by customers, who may factor in workload correlation and load in order to ensure smooth host system operation.
  • With a microVM configured with a minimal Linux kernel, single-core CPU, and 128 MiB of RAM, Firecracker supports a steady mutation rate of 5 microVMs per host core per second (e.g., one can create 180 microVMs per second on a host with 36 physical cores).
  • The number of Firecracker microVMs running simultaneously on a host is limited only by the availability of hardware resources.
  • Each microVM exposes a host-facing API via an in-process HTTP server.
  • Each microVM provides guest-facing access to host-configured metadata via the /mmds API.

Does anyone have any thoughts on the major differences?

Thats what I thought when I read up about firecracker.

I even searched to se if it was an aws rebranding of lxd.

Yeah, they talk about ‘serverless’ in the docs but there’s always an OS and kernel behind the scenes…

I read alot of the reference links and to me… It sounded alot like lxd IMHO