Environment Variables on subprocess Calls

[hftsai256]

Hi all,

I’ve been exploring the possibility of porting this package to NixOS and was able to identify the root cause of the issue. It appears to stem from the subprocess calls that fully purge the environment variables. For example, in localplatformlinux.py:14:

async def run(
    args: list[str],
    stdin: ProcessIO = DEVNULL,
    stdout: ProcessIO = PIPE,
    stderr: ProcessIO = PIPE,
    env: ENV | None = {"LD_LIBRARY_PATH": ""}
)

And in helper.py:99:

capture_output=True,
user=localplatform.localplatform._get_user_id() if localplatform.ON_LINUX else None,
env={} if localplatform.ON_LINUX else None
)

While it’s possible to pass in the full os.environ, it seems that PATH is the most relevant variable in this context. Passing something like env={"PATH": os.environ["PATH"]} is sufficient to work around the issue on NixOS.

May I ask if there is a specific reason for purging all environment variables? From my understanding, preserving the session environment, at least partially, would improve compatibility across different distributions, not just NixOS.

Additionally, since poetry2nix is now deprecated and unmaintained, I updated the pyproject.toml and migrated to uv for improved support. When building the actual Nix package, I rely on system-provided dependencies instead. For reference, the flake I am using is available on my fork:

https://github.com/hftsai256/decky-loader/blob/nixos/flake.nix

I hope this may be helpful for others interested in Nix. Thanks for your time!