Useful Drupal modules

Click on the module name for notes, comments, patches.
Recommendations (for and against) are my personal opinion only and may be out of date. Feel free to email with corrections/suggestions.

Why haven't you mentioned Drupal 9? I will be adding this, but as of August 2021, this site you are reading is the only Drupal site of mine I've been able to upgrade to D9, so although you can check D9 compatibility status of all modules (use upgrade_status, it's superb) I can't speak from personal experience about any of them.

(1 modules in list)
Module name or machine name
Any text in the notes
Name D8 Personally Tested Last Updated
Module builder (module_builder) 2017-02-26

d.o. page

"Essential"

Add a UI to easily create scaffolding for new modules (including hooks, plugins, permissions etc.) NB: first, you need to download drupal-code-builder from GitHub and place it in a /libraries top-level directory (see module builder's README.txt).   You can preview and edit the output files before writing to disk - and each module's configuration is saved  as a node, so you can add another hook etc. at a later date, regenerate the files and copy/paste the extra things you need. Video walkthrough.