Ported a legacy, long in the tooth 15+ year old vB 3.8 forum to Discourse. Sometimes punished for answers tangential questions from members and shutdown for posting migration bugs. So far, I have found (and fixed) many bugs in the Ruby migration scripts. Our team also found a very serious flaw in the
ruby-bbcode-to-md discourse plugin which mangles all code. Our team confirmed this bug. Advice to all migrators, do not use the
ruby-bbcode-to-md plugin under any circumstances. Contact me via message if you need to know how to migrate a large, established forum correctly. I will help you for free as a public service.