this won't work, right?

R.nix

@@ -0,0 +1,19 @@
+{ config, pkgs, ... }:
+
+{
+  home.packages = with pkgs;
+  let 
+    R-packed = rWrapper.override {
+      packages = with rPackages; [
+        jsonlite
+        rlist
+        rvest
+        sf
+        tidyverse
+        tmap
+      ];
+    };
+  in [
+    R-packed
+  ];
+}

home/default.nix

@@ -14,19 +14,7 @@
 
   programs.home-manager.enable = true;
 
-  home.packages = with pkgs;
+  home.packages = with pkgs; [
-  let 
-    R-packed = rWrapper.override {
-      packages = with rPackages; [
-        jsonlite
-        rlist
-        rvest
-        sf
-        tidyverse
-        tmap
-      ];
-    };
-  in [
     exa
     firefox
     fzf
@@ -36,7 +24,6 @@
     neomutt
     nodejs
     qutebrowser
-    R-packed
     rstudio
     ruby
     silver-searcher
@@ -45,6 +32,10 @@
     vdirsyncer
   ];
 
+  modules = [
+    R.nix
+  ];
+
   programs.neovim = {
     enable = true;
     defaultEditor = true;