kdevops-ng

Quick clarification: you don't need full NixOS. Nix (the package manager) installs next to whatever distro you run, so there's no reinstall or infra migration. You keep your usual distro/userland. The tax is that you still have to learn the Nix way, which is probably the "yet another thing to learn" worry from the thread I linked. One payoff: the same /nix/store that boots the guests is what you run on baremetal too, so the two stop being separate setups to maintain.

But Nix is only one of the pieces. In the PoC, systemd runs the VM (and test suite) lifecycle, that let me cut the dependencies for running QEMU and
simplify both the process management and the QEMU incantations -> zero wrappers -> less things to maintain. Windmill ties all this together with a UI and a CLI, and your workflow steps can be in whatever language you like (Python, Bash, Rust, ...).