I know that, but again, I'm asking here because I don't know what I should be exploring. There's something missing in my mental model, and I'm here asking for a nudge in the right direction^^

Answering your suggestion on using the nix repl directly, how can I in the repl explore what the config attribute w/the comments look like? I only know how to explore evaluated configs/outputs in the repl

          {
            name,
            username, # <- I want access to these, that live under `config.flake.modules.x10.device-configs.<a device>,`
            hostname, # <- I want access to these, that live under `config.flake.modules.x10.device-configs.<a device>,`
            system, # <- I want access to these, that live under `config.flake.modules.x10.device-configs.<a device>,`
            ...
          }:
let
  ihnerit (config.flake.modules.x10.device-config.${name}) username;
in
          {
            options.homeManager = {

          {
            name,
            ...
          }:
let
  ihnerit (config.flake.modules.x10.device-config.${name}) username;
in
          {
            options.homeManager = {

          {
            name,
            ...
          }:
let
  inherit (config.flake.modules.x10.device-config.${name}) username;
in
          {
            options.homeManager = {