Focalboard

Focalboard is a self-hosted Trello, Notion, and Asana alternative with Kanban boards, calendars, and table views. It looks good. It works. And the maintainers stopped working on it. The README says it plainly: this repository is currently not maintained. Mattermost moved development to a plugin version at mattermost/mattermost-plugin-boards, which is the place to go if you want to keep getting updates.

If you self-host this version, you get a standalone server you run via Docker or an Ubuntu install. Desktop apps exist for macOS, Windows, and Linux. The data model is solid; the UI is still pleasant. It's stable software, just frozen. No security patches, no new features, no issue triage from the original team.

Solo developers: if you've already deployed Focalboard, keep using it until something breaks, then look at Plane or AppFlowy. Small teams: don't start a new deployment here. The plugin version inside Mattermost is the maintained successor. Large teams: same answer, and the Mattermost plugin route gives you a single platform for chat and project management.

The catch: it's not maintained. The license is also proprietary, not OSI-approved open source. Two reasons to look elsewhere for new work.