Can't use environment variables in rewrite

[danimalquackers]

Hi, I was hoping to be able to specify a rewrite target using XDG environment variables, for example: $XDG_CONFIG_HOME/gemini to point to ~/.config/gemini, or $XDG_CACHE_HOME/$XDG_DATA_HOME. However, including these in my configuration (as below) just creates a directory called $XDG_CONFIG_HOME in the current directory with a gemini folder inside of it. Is there any way to support environment variable evaluation within the rewrite value?

rules:
- context: []
  env: {}
  mode: directory
  name: Gemini CLI
  only: []
  rewrite: $XDG_CONFIG_HOME/gemini
  target: ~/.gemini

System is running NixOS 25.11 with home-manager programs.boxxy, running boxxy version 0.8.5.

[queer]

Hi! (:

This is not currently a feature today. If you are Rust-enabled I would not be opposed to a PR* to add it. It would likely end up being a bunch of preprocessing in https://github.com/queer/boxxy/blob/mistress/src/config/mod.rs to allow pulling values from the environment; ideally it would only be for XDG_* vars or similar.

* please note current maintenance status https://github.com/queer/boxxy?tab=readme-ov-file#maintenance-status