There is a wall of text but how much stuff has happened?

A lot of stuff scrolls past telling X packages have been built but gives no idea about the progress. Pass --log-format bar-wth-logs to nix-env.

nix-env --log-format bar-with-logs -iA nixpkgs.<package>

It will put a nice status in the bottom telling about how much packages have been downloaded and built and how much is left.

I tried putting the option in the config file but it did not work. I could not find the relevant documentation for it either.