Where is avr-ar currently exported?

Doing some AVR work, and one of the things I’m wanting to do is to make archive libraries. I can work around it, but they’re helpful for organizational reasons.

Currently, it appears that avr-ar isn’t exported in pkgsCross.avr.buildPackages.binutils in either 20.09 or unstable. However, I know that it was available at some point as I found this reference: avrgcclibc fails to build · Issue #28220 · NixOS/nixpkgs · GitHub.

When I track things down, I find that the binutils package refers to avr-binutils-wrapper:

nix-repl> "${pkgs.pkgsCross.avr.buildPackages.binutils}"

Sure enough, binutils-wrapper doesn’t include avr-ar. However, there is an avr-binutils derivation that contains avr-ar:

.r-xr-xr-x 80k root 31 Dec  1969 /nix/store/dgfgh2acwim026qy81hbs67hqair9b4s-avr-binutils-2.31.1/bin/avr-ar

What’s the trick to getting access to this?