Basecamp is not available as a self-hosted solution but there are plenty of alternatives for power users and business that want to host a solution on-premise. The best Self-Hosted alternative is Redmine, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Basecamp and loads of them are available as a self-hosted solution so hopefully you can find a suitable replacement. Other interesting Self-Hosted alternatives to Basecamp are Taiga.io (Freemium, Open Source), OpenProject (Freemium, Open Source), Kanban Tool (Paid) and Focalboard (Free, Open Source).
Leantime is a project management system for small teams and startups. Designed to help you manage your projects from ideation to delivery. Leantime's Idea Manager allows you to store ideas, communicate them with team members, discuss and move them from idea to validation.
With SeaTable, teams can easily organize their tasks, assets, projects and ideas. It looks like Excel, but its not limited by text and numbers. SeaTable brings structure to any type of information, in the cloud or on your own server.
Once enabled, a new Tasks menu will appear in your Nextcloud apps menu. From there you can add and delete tasks, edit their title, description, start and due dates, reminder times, mark them as important, and add comments on them. Tasks can be shared between users.