refactor(go): nixify 'GOPATH' environment variable

dots/.bashrc

@@ -82,10 +82,6 @@ else
 fi
 # }}}
 
-# Go {{{
-export GOPATH="${XDG_DATA_HOME}/go"
-# }}}
-
 # Jupyter {{{
 export JUPYTERLAB_DIR=$HOME/.local/share/jupyter/lab
 # }}}

home/modules/go/default.nix

@@ -5,18 +5,18 @@
   ...
 }:
 
-let
-  cfg = config.go;
-in
 {
   options.go = {
     enable = lib.mkEnableOption "Go";
   };
 
-  config = lib.mkIf cfg.enable {
-    home.packages = with pkgs; [
+  config = lib.mkIf config.go.enable {
+    home = {
+      sessionVariables.GOPATH = "${config.xdg.dataHome}/go";
+      packages = with pkgs; [
         go
         gopls
       ];
     };
+  };
 }