The Aggregation of Marginal Gains in Software Engineering

Could this idea, proven to be very successful for sport teams, be applicable to our software engineering team?

1. Improving performance through the aggregation of marginal gains 13th August 2015

2. Agenda What does `the aggregation of marginal gains` mean? Could this improve the performance of our software engineering team?

3. Sir Dave Brailsford Ex-Performance Director , British Cycling General Manager , Team Sky By utilising marginal gains, these teams saw considerable success..

4. British Cycling Olympic Medal Haul 2000 - 2012

5. Team Sky Tour de France British Winners 2012 2013 2015

6. –Sir Dave Brailsford “The whole principle came from the idea that if you broke down everything you could think of that goes into riding a bike, and then improved it by 1%, you will get a significant increase when you put them all together”

7. Sleep posture is important for an athlete The team replaced the mattresses + pillows in every hotel room the riders stayed in

8. We are not a professional cycling team.

9. We are a team. We have goals.

10. requirements code test cases Product Owner User

11. Release early, release often… We want the lightbulb (the Product Owner’s feature) to get round our ‘race track’ in the shortest possible time, but not at any cost. We want to: Get a functioning lightbulb round the track (scope) In the shortest time possible (velocity) Without sacrificing the time for subsequent lightbulbs to get round the track (quality)

12. What could our marginal gains look like?

13. requirements code test cases Product Owner User

14. What goes into the ‘code’ work product?

15. We review code

16. Not all diffs are created equal

17. Work to a maximum number of characters per line: Ideally <80 Definitely <132 It’s much easier to interpret diffs during a code review

18. We debug code

19. Commit messages vary in their usefulness

20. Elliot Carver, Bond Villain “The key to a great story is not who, or what, or when, but why.” commit message

21. We run acceptance-level automation

22. We currently run entire cake + salvos before merge: - this is dead time for a developer - doesn’t expose poorly designed code to other members of the team

23. Developers should only need to run: - @smoketest - relevant scenarios

24. requirements code test cases Product Owner User

25. What goes into our other work products?

26. We define things

27. We define terminology to help us implement a feature That same terminology will be used by the next person who works on that feature

28. Treat terminology as a deliverable Instantly resolve ambiguity you find: >1 term to describe the same thing >1 thing can be described with the same term

29. We deal with surprises

30. Surprises normally slow us down It’s better to move from up-next > blocked , rather than ready-for-test > blocked

31. Developer/Tester chat before up-next -> in-progress is there any unclear terminology here? is this a candidate for a smoke test? does this rely on any 3rd party code? is there any device-specific behaviour? is there anything here that could be difficult to automate?

32. Can this improve the performance of our team?

33. Your actions provide gains to other members of the team :) You’ll experience gains because of someone else’s actions :) However, to really understand performance we need measurements

34. –Sir Dave Brailsford “We're in the right mindset, we're looking for little things, collectively, all the time that's going to make us improve.” collectively

35. ?