Charliecloud vs firecracker-containerd

Charliecloud is free, open-source container software for high-performance computing on Linux. It runs containers without privileged operations or daemons by using Linux user namespaces, with minimal configuration changes on computing-center resources. Users can build images, push and pull them to registries, and use accelerators such as GPUs. Its layer-free build cache is based on Git rather than union-mount filesystems and tarballs, and Dockerfiles are parsed with a formal grammar. The ch-image tool supports registry authentication and registries including GitLab Container Registry. At runtime, ch-run can inject host resources through the Container Device Interface, including NVIDIA GPUs and Cray networking. Installation is available from a release tarball, Git checkout, Spack, or Fedora/EPEL. Charliecloud requires Linux user namespaces and has been run on x86-64, ARM, and Power; current testing covers x86_64 and ARM. It is distributed under Apache License, Version 2.0. The project supports only the current release and provides no internal security boundary.

firecracker-containerd lets containerd manage containers as Firecracker microVMs, adding isolation through the KVM hypervisor. Potential uses include sandboxing untrusted third-party containers and bin-packing different workloads on multi-tenant hosts. It uses OCI image format where possible. The project includes a control plugin and API, an out-of-process shim runtime, an agent inside the microVM, and a root filesystem image builder. That agent invokes runC through containerd-shim-runc-v1 to create Linux containers inside the microVM. Networking supports pre-created tap devices and tap devices created by CNI plugins such as bridge, ptp, host-local, firewall, and tc-redirect-tap. The software is free under Apache 2.0. Hosts require Linux 4.14 or later, Intel x86_64, and KVM; AMD and Arm are not supported. Building requires git, gcc, Docker CE, and Go 1.23 or later. The guide describes the project as very early, and multi-tenant use is at the user’s own risk.