Slides from Alberto Brandolini talk @ codemotion roma 2014

1. Rethinking Enterprise
Software
@ziobrandoCodemotion 2014 - Roma

2. About me
@ziobrando
!
I do something else instead
@ziobrandoAbout me
DDD enthusiast
Post-it addicted
Visual thinker
Chaos summoner
Developer
Idea thief
…never satisfied
Entrepreneur avanscoperta

3. Some news about
software estimation
Even broken models can teach us something

4. The real problem
with estimations:

5. They may be right, sometimes

6. 11 x 2 = …

7. Easy homework

8. What if we have
Legacy?

10. “It’s only a couple of
mines somewhere…”

11. Some recap from
one year ago

12. Ignorance is the single
greatest impediment to
throughput.
Dan North
http://dannorth.net/2010/08/30/introducing-deliberate-discovery/

13. Learning is the
constraint
Dan North
http://dannorth.net/2010/08/30/introducing-deliberate-discovery/

14. Software
development is a
learning process
Working code is a
side effect

15. Learning

16. Memories

17. Learning
School
Boring
Study
Lesson
Experiment
Mistakes
Fun
Marks
Exams
Stress
Life

18. Learning didn’t
happen there

19. Learning is crucial for
our job, and yet we don’t
know much about it
Look inside!

20. Learning is non
linear
(doesn’t fit into spreadsheets, burndown and Gantt charts)

21. Stress
Psychological reaction
!
To an adverse situation
!
Situation is perceived as
inevitable

22. Brain
can’t learn under stress

23. Relax

24. Looks like…

26. Conformity kills
creativity

27. Pressure hurts
problem solving

28. Can you estimate
learning?

29. I haven’t finished,
yet

30. Value Stream Mapping
http://agile.dzone.com/books/continuous-delivery-free

31. A quicker
notation...

32. We need a different
model!
(again)

33. Coding 20cl, learning 20cl,
deciding 20cl, waiting...

34. Mutual waiting
Apparently, a process and organisation issue...

35. Learning is not the
only constraint

36. Deciding?

37. We suck at it

38. How many DDD
practitioners are
needed to name a
class?

39. We should really find a
name for our daughter...
Isn’t a GUID sufficient?
No, I mean a proper
name...
What about Foo now,
and refactor later?

41. Should I marry her?
Yes
No

42. We really should be
getting married soon...
Can we talk about
this another time, honey? I’m
facing a zerg assault right
now...

43. The strategy?

44. Deadline!

45. Wedding ceremony
is a Ponzi schema
designed to stop the
man procrastinating

46. ...but can we stop
afterthoughts?

47. Wow, Kate
looked really hot
today, maybe…
maybe I should
have used MongoDB in
that project

48. Finally, everybody
leaves

49. Can you provide me
an estimate?
You can use *points
if you want…

50. Problem

52. Yes…
there’s no one
size fits all

53. Summary
Repeatable (boring) —> Pseudo-linear
Legacy —> Too guilty to accept the real
numbers
Learning —> Non Linear
Deciding —> Deadlines & acceptable
results
Waiting —> Remove coupling

54. Enterprise software

55. Enterprise software, also known
as enterprise software application
(ESA), is purposed-designed
computer software used to satisfy
the needs of an organization
rather than individual users.

56. Enterprise software, also known
as enterprise software application
(ESA), is purposed-designed
computer software used to satisfy
the needs of an organisation
rather than individual users.

57. Which are the needs
of an organisation?

59. Kanban View of the system:
Decision Making
is the bottleneck

60. A business process is a
series of connected
business-relevant
decisions

61. So what should we
do?

62. Should we
write use
cases?

63. Developers loved templates

64. But forgot
good
readings

66. User Stories
As a [role]
I want to [action]
in order to [goal]

67. Really?

68. A placeholder for
future conversation

69. What are we
supposed to say?

70. meaningful
conversation with
the domain expert

71. “...Eric?”

73. ...even better!

74. Hack!
Warning: DDD doesn’t work on the Death Star

75. Event Storming!

76. Video
If a picture is worth a thousand words…

77. ©
Alberto
Brandolini
2009
#CDays14 – Milano 25, 26 e 27 Febbraio 2014
Video!

81. Yes, I mean that much
space...

82. My best friend

83. And…
no table.

86. It’s no fun to just
watch others play

87. Ubiquitous
Language
Reloaded

88. Model Affinity

89. Domain Events work
better

90. Events are precise

91. Event are meaningful

94. here the user decides
Command
User
issues
influences
External
information
influences
Read Model

95. Quali informazioni

97. Fine-Grained Delegation
Management 30.com

98. Steal and tweak

99. Process fine tuning

100. Conversation
happens here!

101. “Which are the events
needed in order to make
this event happen?”
“Which are the information
needed for a user in order to take
this decision?”
(more or less wisely)

102. “Do you have a story to
describe edge cases?”

103. Some great ideas here...
BDD
Specification
by example
Concrete
scenarios

104. We provided a
dedicated place for
learning to happen

105. Divergence can be
managed or
enforced

106. There is
value in
enforcing
divergence

107. Conflict resolution

108. The only thing they agree on is
fooling us!

109. They’re both right!
Context A
Context B

110. whew!

111. Tool Affinity

113. Simple notation

116. How long is this
cycle?

117. What
about ...minutes?

118. Event Storming
Provides a model of the shared level of
understanding of a complex business process
…I’ve never said it’s the right one!

119. Validate with multiple sources

120. ...Waiting

121. Remove
dependencies…

122. Scrum Way:
—> Cross Functional
Teams

123. but…

124. Stand-up meetings
You’re doing them wrong

125. Loosely coupled
architecture reduces
organisation load

126. Bounded Context
CQRS
Event Sourcing
Reactive Apps

127. … not necessarily a
process problem

128. Coding against an
ecosystem
How do we measure effect on an ecosystem?

129. Definition of Done
- It works on my machine
- Green tests
- Deployed in production
- Up and running
- Users are using it
- We’ve solved the business goal

130. Wrap up:
There is a better model for enterprise apps
!
There are better ways to discover this
model
and learn together around it
!
There are better implementations that
perfectly fit this model

131. I am not
paying for that!

132. Grazie!
Alberto.brandolini@avanscoperta.it
@ziobrando