[kstenerud]

Sandboxing is a VERY HARD problem. I've been working on it for months, and finally have something that's mostly there:

- Sandbox on Linux using Docker, Podman, containerd, gVisor, Kata, Firecracker

- Sandbox on Mac using Docker (Docker Desktop or Orbstack), Podman, Apple containers, Seatbelt, Tart (Tart lets you run simulators).

- Network control

- Secrets control (file mounts or credentials broker)

- NO ambient data (ENV is replaced with a minimal and local-to-sandbox one)

- NO access to your homedir. You have to explicitly mount things you want.

- NO direct access to your workdir: Your work dir is never modified until you apply the changes, either standalone or as a git commit. You can also diff before applying. Git runs sandbox side in case the repo has filters.

- gitignored files never get copied in. The agent never sees them.

- Has built-in support for claude, codex, gemini, aider, and opencode, but you can also launch it in "shell" mode and run whatever you want.

- Supports VS code tunnels, so you can remotely access in VS code if you don't want to use the terminal.

- Full lifecycle support: Launch, attach, stop, restart, wait, one-shot, clone, destroy

- MCP passthrough

- Layered API (golang) if you want to sandbox other things

- Self-contained binary. No external requirements other than the backends you want to use. Defaults to a ~/.yoloai dir for config/data, but you can point it anywhere.

- FOSS

https://github.com/kstenerud/yoloai

[Aldipower]

Sandboxing in a container in Linux isn't hard, if you use lxd/incus which ships with Ubuntu/Debian.

[kstenerud]

It all seems so simple at first. Just launch a container/vm with a base image of your dev environment, mount whatever you need, do your work, and then tear down. Maybe add some iptables rules for good measure. Easy peasy, something any moderately competent dev could do and even put in a quick shell script.

I started with that assumption, but there are a lot more gotchas and security issues than you'd think.

[magimas]

but this seems quite overkill no?

I currently run pi agent in Lima on a Mac with only the code project folder mounted and an extension that prevents pi agent from reading the contents of .env files directly.

Yeah, there probably are some freak situations where this isn't safe enough, but I don't really see any realistic ways this is going to end up badly. Am I overlooking some obvious security holes?

[kstenerud]

I designed it to provide a single interface to agent sandboxing, no matter how far up the security tower you want to go.

It eliminates the manual process steps you end up doing with an ad-hoc system (which gets old the 10th time you do it).

Common weak points:

- The agent can access your homedir.

- The agent can access .gitignored files, which can contain secrets (and are gitignored for this reason).

- The agent has r/w access to your workdir.

- The agent could follow your remote mounted dirs.

- The agent can act in your name with whatever credentials it finds (and it will use them when it tries to be helpful, especially with the gh tool).

- Do you even know what's in the diagnose_problem.sh file it just created and asked permission to run?

- Even the .git dir can be weaponized, such as with evil filters.

- The agent can edit its own process, bypassing the harness controls and giving it the same access as you have (amplified by each credential sitting on that machine).

Meanwhile, you're reflex-hitting ENTER without looking because 99% of the permission prompts are mundane.

And that's before you even get to all of the idiosyncrasies in the backends that will eventually trip you up. The list is quite large and continually growing: https://github.com/kstenerud/yoloai/blob/main/docs/contribut...

[lukewarm707]

i have a photon os vmware, agent has root and docker plus a few api keys with minimal credits.

if it messes up: - no sensitive data is there, so it doesn't really work for serious dev but it's secure for play time

- roll back and fix is done in 10s with ram snapshot

- dollar loss is $10 when it leaks the api key

[UltraSane]

This is exactly what VMs are for.

[kstenerud]

Heh, good luck with that.

[UltraSane]

Explain Mr vague.

[kstenerud]

I've already explained in some sister comments. Sandboxing is one of those things that seems very simple on the surface, and is EXTREMELY complicated once you start actually digging into the implications, gotchas, and security issues. The underlying tools were never designed with this use case in mind, so they need a little help to reach that last mile. And this glue is where all the chaos ensues.

Here's a small sample of the crazy shit you have to deal with: https://github.com/kstenerud/yoloai/blob/main/docs/contribut...

And that's if you're actually following the proper procedures (which are themselves byzantine and tricky to get right).