I would contend the nix ecosystem is sloppy, 3 of the primary projects I use are wrong for various reasons. I'm not really sure what's here beyond a prebuilt image with nix and open code, is there?

Can this be adjusted to give the agents access to environments rather than being boxed into them. You want their exec's and fs work boxed in, and likely you also want them to use multiple agents in multiple envs, or have a single agent leverage multiple envs (i.e. with different permissions available for different tasks). You also likely don't need a full on env when you are making an API call with the right secrets