To comply with the newly added license, we are required to name the top 5 "principal" contributors to the wikis. If the top 5 (+ 1 for good measure) users with the most edits is a valid application of this notion, we have:
As per MariaDB [wiki_en]> select user_id, count(rev_user) as edits_count, user_name from revision, user where rev_user=user_id group by rev_user order by edits_count desc limit 20;
+---------+---------------+
| edits_count | user_name |
+---------+---------------+
| 4358 | Hennevogel |
| 3286 | Rajko m |
| 2444 | Jsmeix |
| 2264 | Saigkill |
| 2227 | Spyhawk |
| 1824 | Ddemaio |
+---------+---------------+