[Bug]: "Cannot open load file: No such file or directory" on NixOS

[GNUqb114514]

Bug summary

I'm trying using Neomacs as a replacement of GNU Emacs, but I ran into problems when Neomacs failed to start with the following error:

Cannot open load file: No such file or directory, /nix/store/mgn5caipn4sqgsrkx8350n3i548jwb21-neomacs-30.0.50-neomacs/share/emacs/site-lisp/site-start
DEBUG: kill-emacs called! arg=0xfffffffffffffffe, restart=(nil)
  Lisp backtrace:
    [0] command-error-default-function
    [1] help-command-error-confusable-suggestions
  End backtrace

I tried removing all configurations but the problem still exists. Using emacs -Q or emacs --no-site-file bypasses the problem.

Steps to reproduce

1. Use programs.emacs.package = pkgs.neomacs in home-manager config;
2. rebuild config and run emacs.

Expected behavior

No response

./src/emacs --build-info output

neomacs-build-info
name: neomacs
neomacs-version: 0.0.1
emacs-package: GNU Emacs
emacs-version: 31.0.50
build-time: 2026-03-10 04:52:12
build-number: 4
git-branch: unknown
git-commit: unknown
git-dirty: unknown
system-type: gnu/linux
system-configuration: x86_64-pc-linux-gnu
configure: x86_64-pc-linux-gnu
features: DBUS FREETYPE GLIB GMP GNUTLS LIBSELINUX LIBXML2 MODULES NOTIFY INOTIFY PDUMPER SECCOMP SOUND SQLITE3 THREADS TREE_SITTER XIM ZLIB
core-backend: emacs-c
runtime-sysname: Linux
runtime-release: 6.19.5
runtime-version: #1-NixOS SMP PREEMPT_DYNAMIC Fri Feb 27 21:05:57 UTC 2026
runtime-machine: x86_64

Extra context

No verbose log available.
Running nix run github:eval-exec/neomacs works.