Wouldn't say 'better' alternative, but I worked on making my own setup that I can trust by implementing a pi extension that leverages smolvm and agent-vault. The VM tooling is controlled by nix flakes. I can't share the source code (developed on company time), but I have a 'spec' of the whole thing, which you should be able to feed to your agent to replicate - https://gist.github.com/mahalel/c4e984292ff90bd4e11269555158...