Continuous delivery is on its way to becoming standard practice for software projects where quality, stability, and time-to-market are paramount. In this talk, Jez will explain the why and what of continuous delivery, discuss the effect of continuous delivery on version control process and practice for teams of all sizes, and explore the implications for practitioners.

1. continuous delivery
@jezhumble
10 september 2014

2. water-
scrum-fall

3. s

4. what is continuous delivery?
reduce the cost, time, and risk of
delivering incremental changes to
users while improving quality

5. production-ready software
fast, automated feedback on the
production readiness of your
applications every time there is a change
— to code, infrastructure, or
configuration

6. continuous delivery
architecture
patterns and practices
collaboration

7. ingredients
configuration management
continuous integration
automated testing

8. Mainline Server
Develop
Build
Build
Local
Workstation
pull
Build
push
✔
Done!
© @martinfowler

9. Mainline Server
Develop
Everyone Commits To
Build
the Mainline Every Day
Build
Local
Workstation
pull
Build
push
✔
Done!
© @martinfowler

10. P1 P2
B1
B1
G1 G2
B1
P1-2
G1-2
P4
B2
P5
P3-4
B2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Mainline
Reverend Green
Feature Branching
© @martinfowler

11. P1 P2
B1
B1
G1 G2
B1
P1-2
G1-2
P4
B2
P5
P3-4
B2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Mainline
Reverend Green
G1-6
P1-5
P1-5
G1-6
Feature Branching
© @martinfowler

12. P1 P2
B1
B1
G1 G2
B1
P1-2
G1-2
P4
B2
P5
P3-4
B2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Mainline
Reverend Green
G1-6
P1-5
P1-5
G1-6
Feature Branching
© @martinfowler

13. P1 P2
B1
B1
G1 G2
B1
P1-2
G1-2
P4
B2
P5
P3-4
B2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Mainline
Reverend Green
G1-6
P1-5
P1-5
G1-6
Feature Branching
© @martinfowler

14. P1
P1 P2
P3
P4
P4
P3 P4 P5
G1
P2
G2
G3
G1 G2 G3 G4
G5 G6
B1 B2
G1
P1
B1
B1
P1-2
G2
G2
P3
B2
B2
G3
P3
G3
P4 P5
P4-5
G4
G4 G5 G6
P2
Professor Plum
Mainline
Reverend Green
Continuous Integration
© @martinfowler

15. P1 P2
B1
Feature Branch
G1 G2
P1
P1 P2
P3
P4
B2
P4
P3-4
B2
P4
P5
P3 P4 P5
G1
P2
G2
G3
G1 G2 G3 G4
G5 G6
B1 B2
G1
P1
B1
B1
P1-2
G2
G2
P3
B2
B2
G3
P3
G3
P4 P5
P4-5
G4
G4 G5 G6
P2
Mainline
Professor Plum
Mainline
Reverend Green
B1
B1
P1-2
G1-2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Reverend Green
G1-6
P1-5
P1-5
G1-6
Continuous Integration
© @martinfowler

16. Feature Branch
Continuous Integration
© @martinfowler

17. Feature Branch
Release Branch
Experimental
Branch
© @martinfowler

18. Grand Prize Fight
© @martinfowler

19. Feature Branching
BAM
Continuous Integration
Big Scary
Merge
© @martinfowler

20. P1 P2
B1
Feature Branch
G1 G2
P1
P1 P2
P3
P4
B2
P4
P3-4
B2
P4
P5
P3 P4 P5
G1
P2
G2
G3
G1 G2 G3 G4
G5 G6
B1 B2
G1
P1
B1
B1
P1-2
G2
G2
P3
B2
B2
G3
P3
G3
P4 P5
P4-5
G4
G4 G5 G6
P2
Mainline
Professor Plum
Mainline
Reverend Green
B1
B1
P1-2
G1-2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Reverend Green
G1-6
P1-5
P1-5
G1-6
Continuous Integration
© @martinfowler

21. Feature Branching
BAM
Continuous Integration
Big Scary
Merge
BIFF Untrusted
Contributers
© @martinfowler

22. Feature Branching
BAM
Continuous Integration
Big Scary
Merge
BIFF Untrusted
Contributers
POW !
In-progress features
© @martinfowler

23. Config File
[featureToggles]
wobblyFoobars: true
flightyForkHandles: false
some.jsp
Feature Toggles
<toggle name=wobblyFoobars>
... various UI elements
</toggle>
forkHandle = (featureConfig.isOn(‘flightlyForkHandles)) ?
new FlightyForkHander(aCandle) :
new ForkHandler(aCandle)
other.java
© @martinfowler

24. Branch by Abstraction
© @martinfowler

25. Application
Library
New!
Library
© @martinfowler

26. Application
Library
Interface implements
New!
Library
© @martinfowler

27. Application
Library
Interface implements
New!
Library
© @martinfowler

28. Application
Library
Interface implements
New!
Library
© @martinfowler

29. Application
Interface implements
New!
Library
© @martinfowler

30. Feature Branching
BAM
No Refactoring
Continuous Integration
Big Scary
Merge
BIFF Untrusted
Contributors
POW !
In-progress features
KA-POW!
© @martinfowler

31. P1 P2
B1
Feature Branch
G1 G2
P1
P1 P2
P3
P4
B2
P4
P3-4
B2
P4
P5
P3 P4 P5
G1
P2
G2
G3
G1 G2 G3 G4
G5 G6
B1 B2
G1
P1
B1
B1
P1-2
G2
G2
P3
B2
B2
G3
P3
G3
P4 P5
P4-5
G4
G4 G5 G6
P2
Mainline
Professor Plum
Mainline
Reverend Green
B1
B1
P1-2
G1-2
G3 G4
G5 G6
B2
G3
P3
Professor Plum
Reverend Green
G1-6
P1-5
P1-5
G1-6
Continuous Integration
© @martinfowler

32. Feature Branching
BAM
Continuous Integration
Big Scary
Merge
BIFF Untrusted
Contributors
POW !
No Refactoring
KA-POW!
In-progress features
© @martinfowler

33. continuous integration
Jason Leyba | http://www.infoq.com/presentations/google-test-automation

35. build quality in
“Cease dependence on
mass inspection to
achieve quality. Improve
the process and build
quality into the product
in the first place”
!
W. Edwards Deming

36. different kinds of testing
Business facing
Functional acceptance
tests
Showcases
Usability testing
Exploratory testing
Unit tests
Integration tests
System tests
Non-functional
acceptance tests
(performance, scaling, ...)
Technology facing
Critique project
Support programming
AUTOMATED
AUTOMATED
MANUAL
MANUAL / AUTOMATED
Diagram invented by Brian Marick

37. deployment pipeline
an automated implementation of your
system’s build, deploy, test, release process
visibility
feedback
control

38. deployment pipeline
Delivery team Version control Build & unit
tests
Automated
acceptance tests
User acceptance
tests
Release
Check in
Feedback
Trigger
Check in
Trigger
Feedback
Trigger
Check in
Trigger
Trigger
Approval
Approval
Feedback
Feedback
Feedback
Feedback

39. infrastructure as code

40. high performing IT is a competitive advantage
“Firms with high-performing
IT organizations were twice
as likely to exceed their
profitability, market share
and productivity goals.”
http://bit.ly/2014-devops-report

41. lead time
“How long would it take your organization
to deploy a change that involved just one
single line of code? Do you do this on a
repeatable, reliable basis?”
Mary and Tom Poppendieck, Implementing Lean Software Development, p59.

42. time to restore service
http://martinfowler.com/bliki/PhoenixServer.html

43. highest correlation with IT performance
!
• “Our app configurations are in a version control system”
• “Our system configurations are in a version control system”
• “Our app code is in a version control system”
• “We get failure alerts from logging and monitoring systems”
• “Developers merge their code into trunk daily”
• “When development and operations teams interact, the outcome is
generally win/win.”
• “Developers break up large features into small, incremental changes.”

44. questions
@jezhumble | jez@getchef.com
http://continuousdelivery.com/
!
© 2014 Chef, Inc. & ThoughtWorks, Inc.