Self-hosted full Atlassian stack (jira, confluence, bamboo, bitbucket) for 6+ years. ~200k tickets. To be honest, it just runs with minimal issues.

Mostly downtime is just upgrades. I can remember a few times we've had to add (JVM) memory as our usage increased. Not sure what we're going to do with the discontinuation of server product line. We self-host to keep source code, etc. more than one configuration mistake (or zero-day) away from exposing it to the world.

We are in the same boat. We are looking at the cloud, but the migration tools are just a pain. I can migrate a project to the cloud from Jira, and it even gives me a report of workflow transitions I have to manualy update/change to fix, which is great.

But then, there is no way to keep it in sync. I have to blow that project away in jira cloud, and migrate it again.

So I Have to hard-cut over projects, on a system that has dozens and dozens of projects, and somehow have people figure out which ones are where. or one really, really ugly night to cut it all over, and hope it goes well.

I'm looking for alternatives, but our team is so invested in some very, very customized workflows, its going to be a pain.

Is there any way to migrate away from Jira, or is it full lock-in? I mean, is there any migration tool or service to Redmine, Gitlab, MantisBT, Trac or whatever?

I think one reason Atlassian was successful is that they always invested a lot of effort in building tools to migrate to their products from any of their competitors (obviously not the other way around).

Self-hosting Jira is running a big Java application that has its own directory structure and talks to a Postgres database. It really isn't hard. Even upgrades are automated using shell scripts, although you do need to manually replace some configuration files afterwords for some damn reason. Configuring Jira is complicated, but that's the same regardless of whether you self-host.

Self-hosted Jira sucked because it was shitty software, not because self-hosting has to suck. Mattermost and Jitsi are easy to self-host, to give two examples that are not complete shit.