Build error in `nix-perl-2.3.16`

Hi, I’m having a difficult time trying to decipher the following build error, that I get when trying to update my NixOS config (nixos-unstable channel). Could anyone point me in the direction of a solution to this?

checking for nix-store... yes
checking for nix-instantiate... /nix/store/zw68c3xydx158ldhz6a2va1j7n9712cm-nix-2.6.0/bin/nix-instantiate
error: getting status of '/__corepkgs__/config.nix': No such file or directory
error: getting status of '/__corepkgs__/config.nix': No such file or directory
error: getting status of '/__corepkgs__/config.nix': No such file or directory
error: getting status of '/__corepkgs__/config.nix': No such file or directory
error: getting status of '/__corepkgs__/config.nix': No such file or directory
configure: creating ./config.status
@nix { "action": "setPhase", "phase": "buildPhase" }
building
build flags: SHELL=/nix/store/07j81a5xy8j1srvf57dl7lxsaihnmfac-bash-5.1-p12/bin/bash
  GEN    Makefile.config
  GEN    lib/Nix/Store.cc
  CXX    lib/Nix/Store.o
cc1plus: warning: command-line option '-Wno-duplicate-decl-specifier' is valid for C/ObjC but not for C++
lib/Nix/Store.xs: In function 'void XS_Nix__Store_isValidPath(PerlInterpreter*, CV*)':
lib/Nix/Store.xs:62:43: error: cannot convert 'char*' to 'const nix::StorePath&'
   62 |             RETVAL = store()->isValidPath(path);
      |                                           ^~~~
      |                                           |
      |                                           char*
In file included from lib/Nix/Store.xs:13:
/nix/store/1ba12mb65y7i4cwiysh3vrv2g2aksbca-nix-2.6.0-dev/include/nix/store-api.hh:359:40: note:   initializing argument 1 of 'bool nix::St
ore::isValidPath(const nix::StorePath&)'
  359 |     bool isValidPath(const StorePath & path);
      |                      ~~~~~~~~~~~~~~~~~~^~~~
lib/Nix/Store.xs: In function 'void XS_Nix__Store_queryReferences(PerlInterpreter*, CV*)':
lib/Nix/Store.xs:73:56: error: no matching function for call to 'nix::Store::queryPathInfo(char*&)'
   73 |             PathSet paths = store()->queryPathInfo(path)->references;
      |                                                        ^
In file included from lib/Nix/Store.xs:13:
/nix/store/1ba12mb65y7i4cwiysh3vrv2g2aksbca-nix-2.6.0-dev/include/nix/store-api.hh:390:30: note: candidate: 'nix::ref<const nix::ValidPathI
nfo> nix::Store::queryPathInfo(const nix::StorePath&)'
  390 |     ref<const ValidPathInfo> queryPathInfo(const StorePath & path);
      |                              ^~~~~~~~~~~~~
/nix/store/1ba12mb65y7i4cwiysh3vrv2g2aksbca-nix-2.6.0-dev/include/nix/store-api.hh:390:62: note:   no known conversion for argument 1 from
'char*' to 'const nix::StorePath&'
  390 |     ref<const ValidPathInfo> queryPathInfo(const StorePath & path);
      |                                            ~~~~~~~~~~~~~~~~~~^~~~

OK, this was due to me having added an overlay to get around https://github.com/edolstra/nix-serve/issues/28. Removing that overlay fixed my problems.