We've adopted Trello wholeheartedly and have worked out a decent solution to what you describe. Our overarching board ("Software Roadmap") consists of "Epic/Sto

We've adopted Trello wholeheartedly and have worked out a decent solution to what you describe. Our overarching board ("Software Roadmap") consists of "Epic/Story" cards. Each of these are large projects we expect to be broken down. In each description of the card is a link to a project board for all the detailed tasks, each of which one developer can work on. It's a hierarchy by convention. When all of the tasks of the project board are done, the card on the roadmap can be archived or moved to the "done" column. YMMV