feature requests • Duplicate tests and features • Reviewing pull requests can be difficult • Easy to miss functionality that is not covered by tests • Cleaning up old code after feature stabilisation
• System is green and ready to ship all the time • Easy for the reviewer to understand system evolution • Fairly easy to accommodate incoming feature requests • Untested code attracts attention • No duplication
fast feedback cycles • Requires experimentation • Has the highest pay-off when similar patterns are replicated • May inherit some design decisions from the older architecture