urunc v0.6.0 Released: Linux Guests, Volume Mounts & CNCF Sandbox

Jul 3, 2025 2 min read

We are thrilled to announce the release of urunc v0.6.0, a feature-packed update that pushes unikernel-native infrastructure even closer to everyday container workflows.

This release marks a major milestone: urunc is now an official CNCF Sandbox Project, a strong signal of our commitment to open collaboration, cloud-native principles, and production-grade reliability.

This release adds support for WASM Mewz unikernels, and significantly, for single-app, Linux-based containers by transforming them into minimal Linux VMs. You can now:

  • Pivot and execute the monitor process from a freshly created root filesystem (chroot)
  • Share the container’s root filesystem with the guest using 9pfs
  • Mount volumes into the container’s rootfs
  • Boot single-application, Linux-based guests, not just unikernels
  • Set CLI options at runtime
  • Pass environment variables into the guest

It also enhances logging and error handling, introduces more intuitive CLI semantics, and brings a polished documentation redesign, complete with a brand new logo and improved usability.

Breaking Changes

  • The useDMBlock annotation has been replaced with mountRootfs, offering a unified way to mount the container rootfs using block devices or shared filesystems.
  • Unikraft CLI handling now reserves argv[0] for consistency with kraftkit’s behavior.

CI/CD & Internals

  • Moved entirely to GitHub-hosted runners
  • Added automated docs publishing, better license checking, and spellchecks (code & docs)
  • Improved isolation and test reproducibility by removing org-wide secret dependencies
  • Refactored CI workflows to facilitate external (non-org) PRs

Full Changelog

Docs, Governance & Community

We’re especially excited about the community-building steps in this release. In addition to technical improvements, we’ve:

  • Introduced clear project governance
  • Published a dedicated security policy
  • Refreshed the README with:
    • Roadmap links
    • Contribution guidelines
    • OpenSSF best practices badge
    • A public Slack channel to join the conversation

We invite developers, researchers, and users to collaborate, share feedback, and help shape the future of Urunc.

CNCF Milestone

Becoming a CNCF Sandbox Project marks an important milestone for urunc. This recognition opens up new collaboration opportunities and validates our vision: to bring secure, low-overhead, unikernel-native execution to cloud-native environments through familiar interfaces and open standards.

For more information, demos, tutorials, and contribution details, visit: https://urunc.io

Try it out

Contact info@urunc.io
GitHub: github.com/urunc-dev/urunc

News