reverie VS hermit

By the way Facebook has a nice library/system for creating neat observability tools using a small amount of rust: https://github.com/facebookexperimental/reverie.

For a structured approach to ptrace/syscall rewriting, you could try FB's reverie. I worked on and used it during an internship a few years back; it's pretty amazing at what it does.

https://github.com/facebookexperimental/reverie

Note that this is a follow-on project from the earlier Dettrace system, which was applied mainly to reproducible builds (as in the academic paper, https://dl.acm.org/doi/10.1145/3373376.3378519, and presented to the Debian Reproducible Builds summit):

- https://github.com/dettrace/dettrace

And one cool part of it is this Rust program instrumentation layer:

- https://github.com/facebookexperimental/reverie

It's good for building OS-emulator style projects or tracing tools.

That's been my experience as well. It lacks support for certain clone(2) flags like CLONE_VFORK[1], which limits the set of non-trivial programs it can run, and since running non-trivial programs is most of the point, I haven't revisited it since it was first announced.

[1] https://github.com/facebookexperimental/hermit/blob/bd3153b4...

A Meta developer responded to an issue of mine on Hermit, and said:

"Just to let you know we're not actively working on Hermit in the team..."

https://github.com/facebookexperimental/hermit/issues/34#iss...

I really like antithesis' approach: it's non-intrusive as all the changes are on a VM so one can run deterministic simulation without changing their code. It's also technically challenging, as making a VM suitable for deterministic simulation is not an easy feat.

On a side, I was wondering how this approach compares to Meta's Hermit(https://github.com/facebookexperimental/hermit), which is a deterministic Linux instead of a VM.

> AMA!

Eager to try it but encountering the build error here - https://github.com/facebookexperimental/hermit/issues/11

Do you have a reference build log / environment you can share? Last known good commit sha and/or output from "rustup show"?

Here is the GitHub repository: https://github.com/facebookexperimental/hermit