Vertical slices with split disciplines

Question

We have a DevOps team which includes a BA, .NET developers and SAP developers. The .NET and SAP developers can and will only work on their particular discipline.

Some of our stories involve only .NET work; These are easy to write. Likewise for the SAP stories.

Some work involves effort which spans right from the user interface (.NET) down to the data store (SAP).

When a latter story is encountered, is the best practice to have one story with discipline-specific tasks (on the basis that a story should be a full vertical slice) or two separate stories (on the basis that each piece is independently worked on)?

The complexity here is that we can't rely on one of each developer being available to work on the story at the same time; Since those two tasks must be done as separate efforts of work (no matter how inter-dependent) it would seem unreasonable/unwise (in this case) to block the whole story because of one task being unable to be completed. (We could forever be waiting for both developers to become available. It is this race condition we want to avoid.)

Answer 1

It needs to be one user story. The user does not care about your resources. A user story needs to provide value and a backend on it's own or a frontend with no functionality is of no use to your user.

Obviously it's two tasks. And your team should commit on doing it... or not doing it. There is no race condition here. Either the two guys can do it, or they cannot. If you are waiting for them to become available I suggest you check if you are actually doing Scrum. Because that can only happen if there is somebody messing with your resources while they are sprinting.