I remember how at one of my previous employers tools team got frustrated with JIRA and created their own knockoff in something like a half year. Was lightning

I remember how at one of my previous employers tools team got frustrated with JIRA and created their own knockoff in something like a half year. Was lightning fast, not crumbling under the amount of issues and projects we had, and interface much cleaner. I understand there's a ton of complexity in JIRA that we didn't use and they didn't have to implement, but anyway there's no excuse how unwieldy JIRA core functonality is.