Error: error: value is null while a set was expected

[joscha]

I am trying to update deno via https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/web/deno/update/update.ts but

https://github.com/NixOS/nixpkgs/blob/35ac2fed3eac0f718257d99f9fb03b9bff46f4fd/pkgs/stdenv/darwin/default.nix#L42 throws

error: Uncaught (in promise) Error: error: value is null while a set was expected

       at /Users/joscha/dev/nixpkgs/pkgs/stdenv/darwin/default.nix:42:52:

           41|   isBuiltByBootstrapFilesCompiler =
           42|     pkg: isFromNixpkgs pkg && isFromBootstrapFiles pkg.stdenv.cc.cc;
             |                                                    ^
           43|

for me on 2.18.5 on Darwin (Apple M1 Max) when executing on 1149f210e77145c56a5c06d4f09a30d89c8ce35b

One command that fails is:

nix-prefetch -f /Users/joscha/dev/nixpkgs deno.src --rev v1.45.2

I can reproduce via:

nix-shell -p nix-prefetch
nix-prefetch -f /Users/joscha/dev/nixpkgs deno.src --rev v1.45.2

Any pointers on what I might be missing?