Scaling Scrum involves using multiple Scrum Teams to produce increments of a ‘large’ product; this will involve more people with the potential communication PROBLEMS.

Of the Agile Technical practices LISTED in the answer to the previous question, the following are essential technical practices when scaling Scrum:

• Simple Design – the simpler the code design used by one team, the easier it will be for other Teams to understand the code if they need to modify it for their own purposes.
• Test-Driven Development (TDD) – With Teams sharing the Product codebase, it is essential that any Team modifying the code produced by another Team must be ABLE to test that their changes do not ‘break’ the original functionality or ‘interfere’ with code from any other part of the system.

The practice of TDD is the only way to ensure that a full suite of tests can be run to test the whole codebase.

• Continuous Integration – with multiple Teams adding to the codebase it is essential that automated integration testing be carried out more frequently than a single Team may use.  The origin of any integration errors can COME from any of the Teams and build problems must be fixed as soon as possible to prevent costly bug-fixing toward the end of a Release period.