# \[ANN\] Solo5 0.12.0

**URL:** <https://discuss.ocaml.org/t/ann-solo5-0-12-0/18320>\
**Category:** Community\
**Tags:** unikernel, release, mirageos, announce\
**Created:** [July 2, 2026, 7:15pm UTC](https://discuss.ocaml.org/t/ann-solo5-0-12-0/18320 "2026-07-02T19:15:09Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![hannes](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ocaml.org/hannes/32/2302_2.png) [@hannes](https://discuss.ocaml.org/u/hannes)\
**Post date:** [July 2, 2026, 7:15pm UTC](https://discuss.ocaml.org/t/ann-solo5-0-12-0/18320/1 "2026-07-02T19:15:09Z")

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We are delighted to announce the release of [Solo5 0.12.0](https://github.com/Solo5/solo5/releases/tag/v0.12.0). This has two distinct features: a new hvt [backend for DragonFlyBSD nvmm](https://github.com/Solo5/solo5/pull/640), thanks to first-time contributor Michael Neumann, and [soft power-off of virtio unikernels](https://github.com/Solo5/solo5/pull/647) - a [long-standing feature request](https://github.com/Solo5/solo5/issues/499), which makes using solo5 e.g. on Google compute much smoother – this was initially requested by Michael Bacarella, including draft implementations, and [now implemented](https://github.com/Solo5/solo5/pull/647) and merged by Romain Calascibetta.

Other noteworthy fixes include that `configure.sh` [now checks for the C compiler version](https://github.com/Solo5/solo5/pull/645) to be at least GCC in version 9 or clang in version 10. The `solo5-hvt-debug` crashed since too strict seccomp rules were applied (since solo5 0.11.0) - thanks to Felix Solcher for opening the [issue](https://github.com/Solo5/solo5/issues/643), and again Romain Calascibetta for the [fix](https://github.com/Solo5/solo5/pull/644).

Awaiting opam-repository merge at [Release of solo5.0.12.0 by dinosaure · Pull Request #30182 · ocaml/opam-repository · GitHub](https://github.com/ocaml/opam-repository/pull/30182)