site-run-file

site-run-file is a variable defined in `startup.el'.
Its value is

"site-start"

Documentation:
File containing site-wide run-time initializations.
This file is loaded at run-time before `~/.emacs'. It contains inits
that need to be in place for the entire site, but which, due to their
higher incidence of change, don't make sense to load into Emacs's
dumped image. Thus, the run-time load order is: 1. file described in
this variable, if non-nil; 2. `~/.emacs'; 3. `default.el'.

Don't use the `site-start.el' file for things some users may not like.
Put them in `default.el' instead, so that users can more easily
override them. Users can prevent loading `default.el' with the `-q'
option or by setting `inhibit-default-init' in their own init files,
but inhibiting `site-start.el' requires `--no-site-file', which
is less convenient.

This variable is defined for customization so as to make
it visible in the relevant context. However, actually customizing it
is not allowed, since it would not work anyway. The only way to set
this variable usefully is to set it while building and dumping Emacs.

You can customize this variable.