Newbie Qn: moving some home manager extraConfig strings into other files

[tidzo]

I want to move some home manager extraConfig strings into a separate file as home-manager.nix is becoming unwieldy.

Given that I have

~/nixos-config/modules/shared/home-manager.nix

and I've put my desired extraConfig for Tmux in

~/nixos-config/modules/shared/config/tmux_extra.conf

how can I reference that file inside home-manager.nix?

I've tried many variations of builtins.readFile but when I try to build, I get errors like

'could not load [my nix store path]/[hash[/config/tmux_extra.conf'

Conceptually I know that I need tmux_extra.conf to be in the nix store but I don't know how to achieve that.

Can anyone help me figure out to do it? Thanks in advance!

[jplee-metaframe]

In modules/shared/home-manager.nix, I have something like:

{ config, pkgs, lib, ... }:

let
  name = "...";
  user = "...";
  email = "...";
in {
  zellij = import ./zellij.nix pkgs;
  git = import ./git.nix pkgs;
  helix = import ./helix.nix pkgs;
  ssh = import ./ssh.nix pkgs;
}

then for example, modules/shared/zellij.nix:

pkgs: {
  enable = true;
  blah blah...
}

However, if you just want to chunk out extraConfig, maybe you can use builtins.readFile.