Sysbox
Sysbox is a free, open-source container runtime for running system workloads in rootless containers on Linux hosts.
What Sysbox is
Sysbox is a free, open-source container runtime for running system workloads in rootless containers on Linux hosts. It is designed for workloads such as systemd, Docker, and Kubernetes that may need a VM-like environment. Its listed uses include Systemd-in-Docker, Docker-in-Docker, Kubernetes-in-Docker, K3s-in-Docker, and Buildx/Buildkit. Sysbox works with OCI-compatible container managers and orchestrators, including Docker and Kubernetes. Linux user namespaces ensure root inside a container has no privileges on the host, while the runtime virtualizes parts of procfs and sysfs. Its security controls also include namespaces, seccomp, cgroups resource limits, and restrictions on initial mounts. Containers share the Linux kernel, so isolation is weaker than with VM-based runtimes. The project describes uses in CI/CD, development and local testing, legacy application hosting, and isolated compute. It supports selected Linux distributions and architectures such as amd64 and arm64; the README recommends at least 4 CPUs and 4 GB RAM. Sysbox Community Edition is free under Apache License 2.0.
Good
- Free and open-source under Apache License 2.0.
- Supports rootless containers and image building.
- Works with Docker and Kubernetes.
- Includes systemd, Docker, Kubernetes, and Buildkit workloads.
Watch out
- Containers share the Linux kernel, unlike VM-based isolation.
- Requires a supported Linux host and architecture.
- Does not support exposing host devices in system containers.
- Support is best-effort through GitHub or Sysbox Slack.
Who it suits
Sysbox suits Linux teams that need to run system workloads in rootless containers, including CI/CD, development, local testing, and isolated compute environments. It is also relevant for Docker or Kubernetes users who need these workloads inside containers.
Verdict
Sysbox supports a range of system workloads in rootless Linux containers, with integrations for Docker and Kubernetes. Its shared-kernel isolation and Linux host requirements are important considerations when deciding whether it fits a workload.
Plans and prices
From Sysbox's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Sysbox Community Edition | Free | Free and open-source · Apache License 2.0 · Linux hosts |
The facts
Each one read from Sysbox's own pages, with the date it was checked.
What it does
- Container manager integrations
- Sysbox integrates with OCI-compatible container managers and orchestrators, including Docker and Kubernetes.checked 8 Oct 2026
- Enterprise edition
- The README says Sysbox Enterprise is no longer offered as a standalone product and was incorporated into Docker Desktop.checked 8 Oct 2026
- Host requirements
- The README recommends at least 4 CPUs and 4 GB RAM, and says the host needs a supported Linux distribution and architecture such as amd64 or arm64.checked 8 Oct 2026
- Isolation
- It uses Linux user namespaces so root inside a container has zero privileges on the host, and virtualizes portions of procfs and sysfs.checked 8 Oct 2026
- License
- The project is licensed under the Apache License, Version 2.0.checked 8 Oct 2026
- Notable limitations
- The security guide says Sysbox does not currently support exposing host devices inside system containers and does not support reducing the allowed syscall set through a Docker seccomp profile.checked 8 Oct 2026
- Security controls
- The security guide describes use of Linux namespaces, seccomp, resource limits through cgroups, and restrictions on initial mounts.checked 8 Oct 2026
- Security limitation
- Sysbox strengthens isolation over regular Docker containers but provides weaker isolation than VM-based runtimes because containers share the Linux kernel.checked 8 Oct 2026
- Support
- Sysbox support is best-effort through the GitHub repository or Sysbox Slack, and Docker subscriptions do not include Sysbox support.checked 8 Oct 2026
- Use cases
- The project describes use in CI/CD pipelines, development and local testing environments, legacy application hosting, and isolated compute environments.checked 8 Oct 2026
- What it does
- Sysbox is a free, open-source container runtime that lets rootless containers run system workloads such as systemd, Docker, and Kubernetes in VM-like environments.checked 8 Oct 2026
- Workloads
- The feature list describes Systemd-in-Docker, Docker-in-Docker, Kubernetes-in-Docker, K3s-in-Docker, and Buildx/Buildkit support.checked 8 Oct 2026
Where it runs
- Linux support
- Sysbox installs on Linux hosts, with documented support for selected Ubuntu, Debian, and other Linux distributions; some listed distro installation paths are marked work-in-progress.checked 8 Oct 2026
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