Looks like I won't be using #emacs #orgmode to build my website any longer. I just figured out how to make #OpenBSD stop griping about "too many open files" when when running "bundle exec jekyll serve".
The answer seems to be "ulimit -n 65536", though for some reason OpenBSD doesn't seem to have a man page for ulimit, and it feels almost like overkill.
@clematis Thanks, but I had tried adjusting settings in login.conf first.
And I haven't gotten away from Emacs. I'm still using it; I'm just not using org-mode to build my website.