I’ve used color coded cards on Scrum boards - green for user story, blue for system story, yellow task cards for design or review work, blue task card for “technical architecture work”, etc. - lots of variations. Sometimes I suggest it, sometimes I don’t. Just part of the box of tools. The one thing that I’ve noticed with this however was the use of pink cards and post-its and how they can be used to connect agile teams and help build an agile enterprise.
My original use of pink cards was for a Scrum board for developers to fix a critical or blocker bug. This was for a team that was just developers - the testers were a completely different team. And the pink card was basically a request for the development team to help un-block the testing team (and dev team would estimate it and decide if they would need to take something else off the board).
I’ve also used pink post-its on Scrum boards to report a blocking issue on a task - just as a way to remind people working on the issue that it is important and to bring it up in standup until the issue is resolved.
On another team that I worked on we sort-of had a Kanban board for release or operations tasks related to the program (multiple projects - one operations team) and if the implementation team had a request to make of them (e.g. database to setup), then we would create a pink card for their board. Basically a pink card is a Please Do This ASAP request. Maybe pink should stand for Please Implement Now, Kind (Sir/Madam).
What I realized is that one way to connect these teams, with their own boards and tasks and stories is that the issue (post-it) is tied to request(s) to resolve the issue (cards) and you could track and connect those issues/tasks that way. So basically, for that first scenario (separate dev and test teams), if the test team had had a board, their pink post-it (the blocking issue) was tied to the pink card for the development team (the issue resolvers). And a board with a lot of pink is a conversation waiting to happen.
Simple and easy way to handle and track issues that need to get done now that I think helps build an agile enterprise.