Which service to use to support users with native integration capability?

Question

Computer networks

Good afternoon.
There is a site on Ruby On Rails. It is required to give users the opportunity to ask questions, point out errors, etc. He identified the following requirements:

• There should be no double authorization (only through the site), no additional fields (name, email)
  
• It is desirable to integrate through a separate page / section on the site, where you could immediately write a question, see the answer and the entire history of correspondence (therefore, many online chats disappear)
  
• The ability to receive unread messages through the API to display response notifications on the site
  
• In terms of UI, the best solution as in Slack, Viber and similar messengers.
  
• Russian language support for the client interface
  

So far I have settled on a chat that can be inserted into the selected HTML block. But, it seems to me that chats are not quite suitable for long-term user support. Maybe there are some ticket systems, or specialized forums?

Answer 1

Have you considered Bitbucket?

Answer 2

It's hard to say for sure... Zendesk would be nice, but English. Omnidesk only comes to mind, but not the fact that all this can.