Can you explain a bit more about the boundary between the environment and my system? Is it just giving read-only access to /usr/lib?
I use an alias to launch a Podman container with opencode in $PWD. It is fully ephemeral aside from the directories I map to it (usually a couple configs). XDG_HOME is local to that working dir. My only frustration is that my image is too minimal but that can be resolved.
This section of the docs might be helpful for you https://droprun.sh/docs/sandbox-overview/#filesystem-layout
This table shows which dirs are exposed from your system: https://droprun.sh/docs/sandbox-overview/#filesystem-layout
Compared to your setup:
* /usr is from your host, so you don't need to maintain a separate image to have programs that you already have installed.
* username, hostname, your current directory and home dir paths are preserved in the sandbox (within a Podman container a home dir is /root)
* environment variables are easy to carry into the sandbox.
* environments are explicit (`drop ls` lists them) and can be removed with `drop rm`, so you don't need to track in which dirs you have started Podman if you want to cleanup XDG_HOME files.
It is likely that your Podman wrapper also solves some of these or they are non-issues for your. If your setup works well, I wouldn't switch to something different.