Don’t limit developers to a single feature. Make them able to participate in other features as well. Kanban will help you with that. It follows the common practice of distributing tasks between columns (commonly: TODO, Doing, Done) but with a particular key-element:
Scrum is an agile framework designed to work with horizontal teams. There is no managers, just team members and customers. If you do something like putting a “manager” above the team you already failed. And the failure will be incremental through the entire project. At the end of the project (if it ends someday) you’ll remember me.