Font changed after NixOS update

[ArtemChandragupta]

Yesterday I updated my NixOS without changing any font-related things, but my waybar font have changed from this: to this: New font seems to be one of nerdfonts, the old font seemed to be the default, but I don't know for sure, so I'll be glad if I find out what kind of font it is.

I have this in my waybar config:

* {
          border: none;
          font-family: JetBrainsMono Nerd Font, sans-serif;
          font-size: 14px;
        }

and this are my system fonts:

fonts.packages = with pkgs; [
  font-awesome
  iosevka
  material-design-icons
  nerdfonts
];

[ordy]

Because your nerd font has been patched with the new version.

left: old version (from a 5 months old copy of JetBrainsMono Nerd Font) right: current version

[ArtemChandragupta]

Are there any good ways to get the old font back, or is it better to rely on upstream?

[ordy]

I'm not familiar with nix but on arch if I needed an older version of the font to display on waybar, I'd just go on NF's repo (https://github.com/ryanoasis/nerd-fonts/commits/master/patched-fonts/JetBrainsMono) and view the code on a previous commit to download to files and then simply copy the TTF to my .local/share/fonts folder.

However that means not getting any update on new icons.

Another option would be to use the base JetBrains Mono and another font with old/different glyphs as a fallback.