20111119 Is Software Evolution really effective? @IAD2011 Rome-IT [ENG]

Anti-IF Campaign:
Is Software Evolution
really eﬀective?
Italian Agile Day
Roma 19.11.2011

Francesco Cirillo • Director, Anti-IF School
francesco@antiifschool.com • @antiifschool

Francesco Cirillo • Director, Anti-IF School Italian Agile Day
francesco@antiifschool.com • @antiifschool Roma, 19.11.2011

About me


The Anti-IF Campaign

Kent Beck Craig Larman

http://www.antiifcampaign.com/join-the-campaign.html


Code Monsters
McCabe Index = 300


Is Software Evolution Really Eﬀective?

What does software evolution really mean?

How much should eﬀective software evolution cost?


Software Development


Is this what really happens?

Not at all!


Software Lifecycles

Requirement 1 Requirement 1
Architecture NFR
Requirement 2 Coding Testing Requirement 2
Analysis
Design FR
Requirement n Requirement n


Software Lifecycles

Architecture NFR
Requirement 2 Coding IT#1 Testing IT#1 Requirement 2
Analysis
Design FR
Requirement n
Coding IT#2 Testing IT#2 Requirement n


Software Lifecycles

Architecture NFR
Requirement 2 [Testing, Coding, Refactoring] IT#1 Requirement 2
Analysis
Design FR
Requirement n
[Testing, Coding, Refactoring] IT#2 Requirement n


Extension versus Change


Software Lifecycles

Requirement 1 Analysis 1 Architecture NFR 1
Coding 1 Testing 1 Requirement 1
Design FR 1

Requirement 2 Analysis 2 Architecture NFR 2
Coding 2 Testing 2 Requirement 2
Design FR 2

Requirement n Analysis n Architecture NFR n
Coding n Testing n Requirement n
Design FR n


Software Lifecycles
Requirement 1 Analysis 1 [Test + Codi ca + Refactoring] 1

[Test + Codi ca + Refactoring] 1


Testing 1? Requirement 1

Requirement2 Analysis 2 [Test + Codi ca + Refactoring] 2





Software Lifecycles
Architecture NFR
Requirement 2 [Testing, Coding, Refactoring] IT#1 Requirement 2
Analysis
Design FR
Requirement n

Requirement 1 Analysis 1 [Test + Codi ca + Refactoring] 1





Software Engineering

da
“Evolutionary
Biology”
Douglas J. Futuyama
1998, pag 653


Evolution
“In biology the term evolution
means the gradual and continuous
accumulation of modifications
over a sufficiently long period of
time in which significant changes
manifest in living organisms”.

Source Wikipedia


Evolutionary process
“It is not the strongest
of the species that survives,
nor the most intelligent
that survives.
It is the one that is the most
adaptable to change.”
Charles Darwin


What is your strategy?


100% Flexible...

IF-based evolution strategy


Emergent


What kind of TDD do you do?
Copyright 200-2006
Scott. W. Ambler

Add a test

[Pass]
Run the tests

Make a little change [Pass,
Development
[Fail] continues]
Run the tests

[Pass, Development stops]


What is the most eﬀective TDD?


Evolution & Emergent
• These words tell us nothing about what should be
done and what should not be done.
• They don’t give you a test as to when to do something
or how to do it.
• They don’t say anything about how that continuous
accumulation of modi cations should happen.

• They just say that your software can be called
evolutionary because it derives from a continuous
accumulation of modi cations.


Is Software Evolution Really Eﬀective?

What does software evolution really mean?
mean

How much should eﬀective software evolution cost?


Earnings
ROI =
Costs


A good startup should
not only generate income
but also have a team
capable of wisely
reducing its costs.


How much does it cost?

How much does...
eﬀective Software Evolution cost?


What about adding similar features
Mature Team’s Marginal Cost

Costs

Mature Team’s
Evolutionary
Marginal Cost
For Similar
Features
Time

Francesco Cirillo • Director, Anti-IF School XPDays Germany
francesco@antiifschool.com • @antiifschool Karlsruhe, 17.11.2011

Adding new features to our system
Evolutionary Marginal Costs

Costs

Eﬀective
Evolutionary
Marginal Costs

Time


Pomodoro Apps


Requirements Pomodoro 1.0

Show a
Pomodoro
background

Set the timer by
pressing a button

Ring after
Total cost:
10.000 €
25 minutes


Lesson #1
Software Evolution costs too much

Francesco: “Would you buy your own software?”

App’s Developer: “NO!”


Is Software Evolution
cost eﬀective?

NO!


Too costly


Lesson #2
Mature teams cost more
20.000 €

Recently formed team
Mature team

10.000 €


Are you really improving your process
or feeding your Code Monster?
Eﬀectiveness of Investment in Process Improvement

Quality
Eﬀort spent
on Process
Improvement

Perceived
internal
quality
of software

Time


Would you buy your own software?

Software can be built in an evolutionary way.

Evolutionary development costs too much.

We are not conscious enough of the strategies.


Do you want to be involved?
Would you buy your own software?

What does the term evolution mean to your team?

Would a team less “mature” than yours have lower costs?
Consider you have to introduce a second feature that is similar
to something you’ve already done. Does it cost less than the
rst time you did it? Why?

http://www.antiifcampaign.com/2011/11/would-you-buy-your-own-software.html


Do you want to be involved?

http://www.antiifcampaign.com/2011/11/would-you-buy-your-own-software.html


Thanks for listening.

Questions?


20111119 Is Software Evolution really effective? @IAD2011 Rome-IT [ENG]

Recommended

Recommended

More Related Content

Similar to 20111119 Is Software Evolution really effective? @IAD2011 Rome-IT [ENG]

Similar to 20111119 Is Software Evolution really effective? @IAD2011 Rome-IT [ENG] (6)

More from Francesco Cirillo

More from Francesco Cirillo (16)

Recently uploaded

Recently uploaded (20)

20111119 Is Software Evolution really effective? @IAD2011 Rome-IT [ENG]