doc.tiki.org was working for some time using Elastic Service online indexing. Today we've done the same to themes.tiki.org , dev.tiki.org and tiki.org (thanks Jonny).
Federated Search is enabled in these 4 sites and tiki-admin_external_wikis.php in each of these has the index configured for the other 3.
doc, themes and dev have been reindexed and tested. As I don't have access to tiki.org, I'll let it reindex overnight (cron). Let's hope all goes well. (Edit: it seems all went well!)