Looks nice (no nix higlighting unfortunately). Also add ~2.8M to closure size. But I think it should be fine.

You could use pygments instead, it has nix support but it will probably increase the closure even more:

--- a/pkgs/applications/misc/ranger/default.nix
+++ b/pkgs/applications/misc/ranger/default.nix
@@ -24,6 +24,9 @@ python3Packages.buildPythonApplication rec {
   '';
 
   preConfigure = ''
+    sed -i -e 's|# pygmentize|${python3Packages.pygments}/bin/pygmentize|' \
+      ranger/data/scope.sh
+
     substituteInPlace ranger/data/scope.sh \
       --replace "/bin/echo" "echo"

It's working nicely on NixOS 👍

Annoying that pygments and highlight have different command line arguments, so you can't just swap them with overrides…

I think that leaving it as highlight would be better as the default, since that's what upstream does. Then all we're doing is fixing a path rather than changing upstream's functionality.

I think that leaving it as highlight would be better as the default, since that's what upstream does.

Agree. Users can easily switch to pygmentize in their ~/.config/ranger/scope.sh