Presentation to London Continuous Delivery Group on Conway's Law January 2014

1. Conway’s Law &
Organizational Change
Continuous Delivery
Allan Kelly
London
allan@softwarestrategy.co.uk
January 2014
http://www.softwarestrategy.co.uk
Twitter: @allankelly.net

2. Allan Kelly…
 Consulting on software
development & strategy
 Training for Agile
Author
– Changing Software Development: Learning to be
Agile (2008, Wiley)
– Business Patterns for Software Developers (2012,
Wiley - ISBN: 978-1119999249)
– Xanpan: Reflections on agile (work in progress)
https://leanpub.com/xanpan
Chapters in…
• Business Analysis and Leadership, Pullan & Archer 2013
• 97 Things Every Programmer Should Know, Henney, 2010
• Context Encapsulation in Pattern Languages of Program
Design, vol #5, 2006

3. Conway’s Law? Continuous Delivery?
Jonathon’s Run Fall, Pennsylvania by Hubert Stoffels (http://flickr.com/photos/22195940@N00)
Creative Commons License

4. The Laws which Rule over Us
Moore’s Law Computing power doubles every 1824 months
Metcalf’s
Law
Conway’s
Law
Brook’s Law
Goodhart’s
Law
Network becomes more useful the
more devices are connected to it
Organizations design systems which
copy the organization
Adding more people to a late
project makes it later
Making a target from a measure
changes the measure

5. Conway’s Law
organizations which design systems (in
the broad sense used here) are
constrained to produce designs which are
copies of the communication structures
of these organizations
Melvin Conway, Datamation, 1968
http://www.melconway.com/Home/Conways_Law.html

6. Raymond on Conway
Conway’s Law prov. The rule that
organization of the software and the
organization of the software team will
be congruent; originally stated as ‘If you
have four groups working on a
compiler, you’ll get a 4-pass compiler’.
Eric Raymond, Hacker’s Dictionary, 1996

7. Coplien & Harrison
If the parts of an organization (e.g. teams,
departments, or subdivisions) do not closely reflect
the essential parts of the product, or if the
relationship between organizations do not reflect
the relationships between product parts, then the
project will be in trouble. ...
Therefore: Make sure the organizations is
compatible with the product architecture.
Coplien & Harrison, Organizational Patterns of Agile
Software Development, 2004

8. The Holomorphic Force
Definition:
Homomorphism is a structure-preserving map
between two structures
Taken from algebra
Leads to Reverse Conway’s Law:
“Organizations with long lived systems will
adopt a structure modeled on the system”

9. Kelly’s Corollary
Organization design is system design.
Architect the organization to architect
the system.
e.g. Separate Teams ->
Separate Modules
Allan Kelly
Many times since 2005
e.g. Collective Code
Ownership leads to more
integrated team & code

10. http://en.wikipedia.org/wiki/File:Shiptriplet2wiki.jpg
CCL image from Lance Rolf
Why do large systems disintegrate?
3 steps to disintegration (from Conway):
1. Designers realize the system will be large … irresistible the
temptation to assign too many people to a design effort
2. Conventional management of large design organization
causes its communication structure to disintegrate
3. Homomorphism: system structure disintegrates to reflect
design organization

11. Kelly’s Laws
Project scope will always increase in
proportion to resources
Kelly’s first law of project complexity
Inside every large project there is a small
one struggling to get out
Kelly’s second law of project complexity

12. May the Force be with you
Can you break
Conway’s Law?
No
The (Homomorphic)
force is stronger than
you
Use the (Homomorphic)
force, Matthew

13. Go against it and
you’ll get a mess
Use the force
Work with it
Wood picture from Böhringer, Creative Commons License
http://commons.wikimedia.org/wiki/File:Zebrano01.jpg

14. Therefore…
• Advice for CD

15. Whole team: Include everyone
• Developers, Testers, Analysts, Product
Managers, etc. etc.
– Don’t add communication barriers
• Absorb/Embed the business
– Keep communication paths short
• One team to rule them all
– No communication divide
– No “us & them”
– One goal

16. Start small: Delay staffing
• Minimize communication boundaries
• Start with smallest team possible
– Minimally Viable Team
– Slightly smaller than you think you need
– Co-locate!
• Get a small system working
– Piecemeal growth
– Grow the team with the system

17. Multi-skilled Willing Staff
• All hands, one team
– Minimize titles
Every man an
rifle man
• Don’t use technologies that
require black arts specialists
– e.g. Databases which need DBA
Debbie Does Development
Chris Oldwood
US Marine
Corps

18. Ameba teams
• Start small
– 1, prototype or research
– 2, get going: Engineer & BA
• Grow
• Split as appropriate
– Focus team
– 1 project or area
• Fully staff each team – stand alone

19. Team & Duration
Prefer
– Short and Fast
Over
– Long and Thin
•
•
•
•
Faster time to market
Higher Rate On Investment
Less resource contention
Requires clear prioritization & closure

20. #NoProjects
• Keep the team together
– Grow them, shrink them,
– Bend them, shake them
– But never disband them
• Why break up a performing team?
– Flow the work to the team
– Continuous flow

21. Avoid Rock-Stars
•
•
•
•
•
Expensive (but talented)
Temperamental
Unpredictable
Prone to outages
Demand flowers
– And chocolates
Are these
attributes you
want for your
system?

22. Conway’s Second Law?
This point of view has produced
the observation that there's never
enough time to do something
right, but there's always enough
time to do it over.
Melvin Conway, Datamation, 1968
http://www.melconway.com/Home/Conways_Law.html

23. You must remember this…
What ever you do….
Start small
and grow
… incremental is not a dirty word

24. Read all about it
How to Committee invent?
– Original paper, Mel Conway
– http://www.melconway.com/Home/Conways_Law
.html
What do we think about Conway’s Law now?
– Hvatum & Kelly, 2005
– http://www.allankelly.net/static/presentations/Eu
roPLoP2005/ConwaysLawFocusGroup.pdf

25. Questions?
Allan Kelly
allan@softwarestrategy.co.uk
http://www.softwarestrategy.co.uk
Twitter: @allankellynet
Xanpan: Reflections on agile (work in progress)
https://leanpub.com/xanpan