PLANKA is a real-time, self-hosted Kanban board built with React, Redux, and PostgreSQL that closely mirrors Trello's visual layout and interaction patterns, right down to draggable cards, lists, labels, and due dates. It supports Kanban, grid, and list board views, deadline and time tracking on individual cards, a REST API with 50+ webhook events for external integrations, and single sign-on through Google, Azure AD, and other OIDC providers. Note that while Planka's source is publicly visible on GitHub, it is distributed under a custom Fair Use License rather than an OSI-approved open-source license, restricting things like cross-company use and commercial hosting; the free Community tier is intended for internal organizational use, with cross-team collaboration features gated behind a paid Pro plan.