Hi Charles, ob-R.el requires ess and the (require 'package) makes sure the ~/.emacs.d/elpa/ directory was added to the load path. But you were somewhat right already: the loaded ESS was years old and caused the issue. Thanks for your help! Christian On Sun, 2022-05-15 at 19:58 +0000, Berry, Charles wrote: > > Um... > > > On May 15, 2022, at 2:46 AM, Christian Heinrich wrote: > > > > I run > > > > emacs -q --load /tmp/init.el --file=/tmp/test.org > > > > with my /tmp/init.el being only > > > > > (require 'package) > > > (package-initialize) > > > (add-to-list 'load-path "~/.emacs.d/straight/repos/org/lisp/") > > > (require 'org) > > > > > > ;(require 'ess-site) > > The line above is commented out. So how do you load ess-site? > > > > > (org-babel-do-load-languages > > >   'org-babel-load-languages > > >    '((R . t))) > > > > I hope this constitutes a minimal example for a config - please correct me if I'm wrong. > > > Just spitballing here: > > Have you tried instrumenting `org-babel-R-evaluate-session'? > > Maybe watching changes made to the session buffer on first evaluation and comparing to subsequent > evals helps. > > HTH, > Chuck >