Checklist from https://www.mediawiki.org/wiki/Writing_an_extension_for_deployment#Process (read this on-wiki for links and examples):
**Prerequisites:** {T347896}
[] 1. Add the new extension submodule to the git mediawiki/extensions repo.
[] 2. Move your extension's CI config to the "Wikimedia production" section, add the "in-wikimedia-production" job template, and make sure it has and passes all the expected jobs for production code.
[] 3. Add your extension to the json make-wmf-branch release tool at least two weeks prior to your target date for enabling on the Beta Cluster.
[] 4. Add your extension to extension-list.
[] 5. Create database schema in beta wikishared (create subtask, see https://wikitech.wikimedia.org/wiki/Creating_new_tables)
[] 6. Add your extension config variable to InitialiseSettings.php and set it to be default false.
[] 7. Add your extension config variable (same as in previous step) to InitialiseSettings-labs.php and set it to be true on Beta Cluster wikis you want it to be on. You may want to turn it off for loginwiki (which doesn't have most extensions).
[] 8. Load your extension in CommonSettings-labs.php.
[] 9. Add to the `"Extensions used by Wikimedia - Upcoming"` group in translatewiki
**Then:** Production deployment (task TBC)