Drupal
Drupal is an incredibly powerful development frame work that can do just about anything. It used to be my go-to website system, but I got a bit disenchanted with version 8. Probably adopted it too early, and needed too much beta software, too many developer versions of developer tools. Version 7 was brilliant and I should have stuck with that untill 8 was a bit older.
Oddly enough - 8 is the same age as Harry, and Harry has come a long way in three years :-0