Better Instructions on how to setup the flake.nix file

[Martinius]

Could you please describe at which point the changes in the flake.nix and home.nix files have to be performed?

My flake.nix looks like this:

  description = "NixOS configuration";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    home-manager.url = "github:nix-community/home-manager";
    home-manager.inputs.nixpkgs.follows = "nixpkgs";
    scientific-fhs.url = "github:olynch/scientific-fhs";
  };

  outputs = inputs@{ nixpkgs, home-manager, ... }: {
    nixosConfigurations = {
      Workstation_M270t = nixpkgs.lib.nixosSystem {
        system = "x86_64-linux";
        modules = [
          ./configuration.nix
          ./home.nix
        ];
      };
    };
  };
}

And my home.nix looks like this

{ config, pkgs, ... }:
  let
    home-manager = builtins.fetchTarball{
    url = "https://github.com/nix-community/home-manager/archive/release-23.05.tar.gz";
    sha256 = "0dfshsgj93ikfkcihf4c5z876h4dwjds998kvgv7sqbfv0z6a4bc";};
  in
  {
    imports = [
      (import "${home-manager}/nixos")
    ];
    # Begin home-manager directives
    home-manager = {
  	useUserPackages = true;
        useGlobalPkgs = true;
        users.martinius = { pkgs, ... }: {
          home.stateVersion = "18.09";
          # Everything inside here is managed by Home Manager!
          programs.home-manager = {
            enable = true;
          };
	  imports = [ inputs.scientific-fhs.nixosModules.default ];

	  programs.scientific-fhs = {
	    enable = true;
	    juliaVersions = [
	      {
	        version = "julia_18";
	        default = true;
   	      }
	      { version = "julia_17"; }
	      { version = "julia_16"; }
	    ];
	    enableNVIDIA = false;
	  };
          home.sessionVariables = {
    	    EDITOR = "gedit";
    	    BROWSER = "firefox";
            TERMINAL = "alacritty";
         }; 
    };
  };
  }

[vereym]

Have you tried installing other programs through home-manager to see if that works?

I'm quite new to nix so not sure about it, but I thought you need to provide home-manager with a homeConfigurations set, so maybe that's the problem? :S