Kuasar

Spec sheet

What it does

Kuasar is an efficient multi-sandbox container runtime for cloud-native container workloads.Read 7 Oct 2026 · kuasar.io

Product

Kuasar is a low-level, multi-sandbox container runtime for managing container and sandbox lifecycles.Read 8 Oct 2026 · kuasar.io

License

Kuasar is licensed under Apache 2.0 and is free for personal or commercial use.Read 7 Oct 2026 · kuasar.io

Founded

2023Read 28 Sep 2026 · kuasar.io

App kernel support

The app kernel sandboxer page says Quark is currently supported.Read 8 Oct 2026 · kuasar.io

Architecture

Kuasar consists of Kuasar-sandboxer for sandbox lifecycle and resource allocation management and Kuasar-Task for container lifecycle and resource allocation management.Read 8 Oct 2026 · kuasar.io

Colocation

Kuasar supports running multiple types of sandboxes on a single node.Read 7 Oct 2026 · kuasar.io

Container runtime integration

Kuasar connects to high-level container runtimes through a sandboxer plugin and the Sandbox API; the overview names containerd, CRI-O, Docker, and iSulad as examples of high-level runtimes.Read 7 Oct 2026 · kuasar.io

Device management

The maker says Kuasar separates sandbox device management logic from container device management to reduce resource residue problems.Read 7 Oct 2026 · kuasar.io

Implementation

Kuasar is written in Rust.Read 7 Oct 2026 · kuasar.io

Isolation

The microVM sandboxer uses virtual machines and Linux kernels, and its page says container I/O can be exported via vsock or uds.Read 8 Oct 2026 · kuasar.io

Language

The project homepage says Kuasar is written in Rust.Read 8 Oct 2026 · kuasar.io

License and cost

The homepage says Kuasar is licensed under Apache 2.0 and free for personal or commercial use.Read 8 Oct 2026 · kuasar.io

Limitations

The Wasm sandboxer documentation says Wasm sandboxes may have constraints for some applications.Read 8 Oct 2026 · kuasar.io

MicroVM support

The microVM sandboxer supports Cloud Hypervisor, StratoVirt, and QEMU.Read 8 Oct 2026 · kuasar.io

MicroVM support limit

The MicroVM sandboxer documentation says only Cloud Hypervisor, StratoVirt, and QEMU are currently supported.Read 7 Oct 2026 · kuasar.io

Performance claim

The homepage claims 2× startup speed and 99% reduction in shim overhead from its optimized framework.Read 8 Oct 2026 · kuasar.io

Project affiliation

The site identifies Kuasar as a Cloud Native Computing Foundation sandbox project.Read 8 Oct 2026 · kuasar.io

Project status

Kuasar is a Cloud Native Computing Foundation sandbox project.Read 7 Oct 2026 · kuasar.io

Runtime integrations

The documentation names containerd, CRI-O, Docker, and iSulad as examples of high-level container runtimes.Read 8 Oct 2026 · kuasar.io

Sandbox API

It connects to high-level container runtimes through a sandboxer plugin and Sandbox API.Read 8 Oct 2026 · kuasar.io

Security positioning

The maker describes Kuasar as balancing security isolation, startup speed, and standardization across sandbox types.Read 7 Oct 2026 · kuasar.io

Support channel

The project’s contributing page lists [email protected] for reporting abusive or unacceptable behavior.Read 7 Oct 2026 · kuasar.io

Supported sandboxes

The site lists Cloud-Hypervisor, StratoVirt, WasmEdge, and Quark as supported sandboxes.Read 8 Oct 2026 · kuasar.io

Wasm support

The Wasm sandboxer page says WasmEdge is currently supported.Read 8 Oct 2026 · kuasar.io

Wasm support limit

The Wasm sandboxer documentation says only WasmEdge is currently supported.Read 7 Oct 2026 · kuasar.io

Where Specifiction places it

• Container Runtime Software#18 of 287.5