For teams looking to stay on-prem or move off Atlassian’s stack, we’ve been working on integrating XWiki (for structured documentation) and OpenProject (for project management).

Both are open-source and can be self-hosted, with integrations for linking tasks, requirements, and project docs. We’re hosting a live demo + Q&A on Nov 19 showing how it works in practice.

[For full disclosure] I’m part of the XWiki team, and I'd be happy to answer any questions about this.