L14 - Continuous Delivery 2

Question 1

What are the 7 principles of Continuous Delivery?

Answer 1

• Create a repeatable process
• Automate as much as you can
• Version control for everything
• If it hurts, do it more frequently
• Build quality in
• Done means released
• Everyone is responsible
• Continuous Improvement

Question 2

What is meant by ‘Create Repeatable Processes’?

Answer 2

• Processes should always be repeatable in CD
• Can give it to other people, who can run the same tests and get the same answers
• Automated repeatable testing ensures repeatable processes

Question 3

What is meant by ‘Automate as much as you can’?

Answer 3

• Computers are more reliable that humans
• Computers are much faster and more predictable than humans
• Easily repeatable

Question 4

What is meant by ‘Version Control for Everything’?

Answer 4

• Including source code, dependencies, commends, documentation etc.
• One button push to revert to a previous version
• Another example is that if a customer comes in with issues with a previous version of software, developers can go back to source code of the version to fix issue

Question 5

What is meant by ‘If it hurts, do it more frequently’?

Answer 5

• If you release often, it makes it less of a big deal e.g every 2 weeks
• Make the scary and dangerous become a routine
• Improvement is made with practice, to iron out kinks in the process and make releasing more efficient

Question 6

What is meant by ‘Build quality in’?

Answer 6

• Defects should be fixed as soon as they’re detected
• Discover errors as you make them
• Doing this ensures that troubleshooting is done when the code just written is fresh, making it easier to think about and resolve

Question 7

What is meant by ‘Done means released’?

Answer 7

• Only time you can say a feature is ‘done’, is when it’s in production and being used by end users
• Only truly know when product is ‘done’ when a customer is using it and is satisfied with it
• Humble and Farley are binary regarding done → Either in production and done, or not

Question 8

What is meant by ‘Everyone is responsible’?

Answer 8

• Succeed and fail as a team
• Prevents siloed development
• Prevents bickering when something goes wrong, and ensures focus is on fixing the issue

Question 9

What is meant by ‘Continuous Improvement’?

Answer 9

• Constantly reflect on what’s gone well and badly, and how to improve on processes in the future
• Mistakes are to be learnt from, not feared
• Feedback should be enabled across development silos → Enables general optimisation as opposed to local optimisation