Presentation to Agile Support group inside Federal Reserve Bank in San Francisco on October 25, 2010.

1. Managing Software Debt
Continued Delivery of High Value as Systems Age
Chris Sterling
VP of Engineering
AgileEVM Inc.
Web: www.AgileEVM.com
Email: chris@agileevm.com
Blog: www.GettingAgile.com
Follow Me on Twitter: @csterwa
Hash Tag for Presentation: #swdebt
1Thursday, October 28, 2010

2. © 2009-2010,
Chris Sterling – AgileEVM Inc.
Developer of AgileEVM ( www.AgileEVM.com ), a
project portfolio decision support tool
Technology Consultant, Agile Consultant and
Certified Scrum Trainer
Consults on software technology, Agile technical
practices, Scrum, and effective management
techniques
Innovation Games® Trained Facilitator
Open Source Developer and Consultant
Software technology, architecture, release
management, monitoring, and design consulting for
Agile Teams
Publishing book with Addison-Wesley called
“Managing Software Debt” - due out Dec 2010
2
Email: chris@agileevm.com
www.AgileEVM.com
Web: http://www.sterlingbarton.com
Blog: http://www.gettingagile.com
Follow me on Twitter: @csterwa
2Thursday, October 28, 2010

3. © 2009-2010,
Brent Barton - AgileEVM Inc.
President, AgileEVM Inc.
More than 15 years software development in many roles
as both employee and consultant for organizations from
small start ups to multinational corporations
Former CTO. Active Agile Coach, Mentor, Certified Scrum
Trainer
Actively involved in Agile Rollouts from small Product
companies to very large IT organizations
Scrum Articles
“AgileEVM – Earned Value Management
in Scrum Projects”, IEEE
“Implementing a Professional Services
Organization Using Type C Scrum”, IEEE
“Establishing and Maintaining Top to
Bottom Transparency Using
the Meta-Scrum”, AgileJournal
“All-Out Organizational Scrum as an
Innovation Value Chain”, IEEE
3
www.AgileEVM.com
Email: brent@sterlingbarton.com
Web: http://www.sterlingbarton.com
Blog: http://www.gettingagile.com
Follow me on Twitter: @brentbarton
3Thursday, October 28, 2010

4. © 2009-2010,
Topics Being Covered
Problems Found with Aging Software
Software Debt Explained
Technical Debt
Quality Debt
Configuration Management Debt
Design Debt
Platform Experience Debt
The Wrap Up
A Story of What is Possible
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5. © 2009-2010,
Problems Found with Aging Software
Software gets difficult to add features to as it ages
Business expectations do not lessen as software ages
Software must remain maintainable and changeable to meet needs of
business over time
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6. © 2009-2010,
Lack of emphasis on software quality attributes
contributes to decay
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7. © 2009-2010,
The “Rewrite”, “NextGen” or “Like-to-like Migration”
“It will be easy since we worked on the original version” - although we
understand the domain we will be fighting with new features, technology,
tools, and processes
“We don’t have any other options” - Refactoring and test automation are
potential alternatives to like-to-like migrations.
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8. © 2009-2010,
Limited Platform Expertise
Risk and costs increase as expertise becomes more
limited for aging software platforms.
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9. © 2009-2010,
Costs for Release Stabilization Increase Over Time
0
125000
250000
375000
500000
Release 1
Release 2
Release 3
Release 4
Release 5
Release 6
Cost of Fixing Defects Cost for Feature Dev
9Thursday, October 28, 2010

10. © 2009-2010,
Extreme Specialization
Knowledge and capability to maintain legacy software decays with time
Costs to maintain rarely used software platforms are higher
Leads to waiting for people in specialized roles to finish their tasks in
support of development effort
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11. Software Debt
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Creeps into software slowly and leaves organizations with liabilities
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12. © 2009-2010,
Software Debt Creeps In
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13. © 2009-2010,
Software Debt Creeps In
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14. © 2009-2010,
Software Debt Creeps In
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15. © 2009-2010,
Managing Software Debt – an Overview
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16. © 2009-2010,
Managing Software Debt
16
It is impossible to stop software debt from creeping into our software
Managing debt in software is based on putting frequent feedback
mechanisms in place for code, quality assurance, configuration
management, design, and organization of people on project team
Feedback mechanisms should be frequent, automated, and easy to use to
support their continued use or modified to new needs
16Thursday, October 28, 2010

17. © 2009-2010,
Types of Software Debt
Technical Debt
Quality Debt
Configuration Management Debt
Design Debt
Platform Experience Debt
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18. Technical Debt
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Issues in software that will impede future development if left unresolved
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19. © 2009-2010,
* Ward Cunningham on “Technical Debt”
Technical Debt includes those internal things that you choose not to do now,
but which will impede future development if left undone. This includes
deferred refactoring.
Technical Debt doesn’t include deferred functionality, except possibly in
edge cases where delivered functionality is “good enough” for the customer,
but doesn’t satisfy some standard (e.g., a UI element that isn’t fully
compliant with some UI standard).
* Ward Cunningham - “Technical Debt” - http://c2.com/cgi/wiki?TechnicalDebt
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20. © 2009-2010,
My Definition of “Technical Debt”
“Technical debt is the decay of
component and inter-component
behavior when the application
functionality meets a minimum standard
of satisfaction for the customer.”
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21. © 2009-2010,
Regression Costs - Manual vs. Automated
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22. © 2009-2010,
Principles of Executable Design
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The way we design can always be improved.
We’ll get it “right” the third time.
We will not get it “right” the first time.
Design and construct for change rather than longevity.
Lower the threshold of pain.
If we are not enhancing the design then
we are just writing a bunch of tests.
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23. Quality Debt
A lack of quality will lessen the value per feature added over time
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24. © 2009-2010,
Accrual of Quality Debt with Releases
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25. © 2009-2010,
Break/Fix Only Prolongs the Agony
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26. © 2009-2010,
Effect of Project Constraints on Quality
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27. © 2009-2010,
Effect of Project Constraints on Quality
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28. © 2009-2010,
Acceptance Test-Driven Development
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29. A Fit Case Study
Cost reduction using Fit for test automation and data conversion
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30. © 2009-2010,
Manual Regression Testing
Testing was taking 75 person hours during 2 full test runs consisting of:
Comprehensive manual regression testing
Data conversion and validation
Cost for testing was $17,000 each iteration
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31. © 2009-2010,
Introducing Fit into Testing Process
After 8 iterations team had introduced healthy amount of Fit fixtures and
automated tests
Reduced 70+ hour test runtime down to 6 hours which now included:
Fit automated regression testing
Data conversion and validation automated with Fit fixtures
Reduced cost of testing each iteration from $17,000 to $7,000
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32. Configuration Management Debt
Unpredictable and error-prone release management
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33. © 2009-2010,
Traditional Source Control Management
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34. © 2009-2010,
Traditional Source Control Management
32
Main Branch
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35. © 2009-2010,
Traditional Source Control Management
32
Main Branch
Version 1
Branch
Integrate for
Version 2
Code
Complete
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36. © 2009-2010,
Traditional Source Control Management
32
Main BranchDebt
Death March
Version 1
Branch
Integrate for
Version 2
Code
Complete
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37. © 2009-2010,
Traditional Source Control Management
32
Main BranchDebt
Death March
{Debt accrues quickly within stabilization periods
Version 1
Branch
Integrate for
Version 2
Code
Complete
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38. © 2009-2010,
Flexible Source Control Management
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39. © 2009-2010,
Flexible Source Control Management
33
Main Branch
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40. © 2009-2010,
Flexible Source Control Management
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Main Branch
Version 1
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41. © 2009-2010,
Flexible Source Control Management
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Main Branch
Version 1 Version 2
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42. © 2009-2010,
Flexible Source Control Management
33
Main Branch
Version 1 Version 2
{Not Easy! Must have proper infrastructure to do this.
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43. © 2009-2010,
Continuous Integration
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44. © 2009-2010,
Scaling to Multiple Integrations
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45. © 2009-2010,
The Power of 2 Scripts: Deploy and Rollback
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Deploy Rollback
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46. Design Debt
Design decays when not attended to so design software continually
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47. © 2009-2010,
* Abuse User Stories
38
Implement Security
for User Information
* From “User Stories Applied” presented by Mike Cohn Agile 2006
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48. © 2009-2010,
* Abuse User Stories
38
Implement Security
for User Information
As a Malicious Hacker I
want to steal credit card
information so that I can
make fraudulent charges
* From “User Stories Applied” presented by Mike Cohn Agile 2006
38Thursday, October 28, 2010

49. Platform Experience Debt
Silos of knowledge and increased specialization will increase cost of
maintenance over time
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50. © 2009-2010,
How to Combat Platform Experience Debt
Ignore it (I do not suggest this!) Surround existing functionality
with automated functional tests
Wrap platform interfaces with
adapters
Transfer knowledge of platform to
more people
Rewrite on more current platform
Move thin slices of functionality to
newer platform
Start platform upgrade
discussions and rearrange teams
into known effective team
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~OR~
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51. © 2009-2010,
Team Configuration Patterns
Virtual Team Pattern
Integration Team Pattern
Component Shepherd Pattern
Team Architect Pattern
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52. © 2009-2010,
Virtual Team Pattern
Enterprise
Planning
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53. © 2009-2010,
Virtual Team Pattern
Pros
Share architecture ideas and needs across teams
Based on verbal communication
Cons
Usually singles out special Team Member role
Could lead to top-down architecture decisions
IT may gain extensive influence and begin to run Product Backlog
prioritization for architecture needs
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54. © 2009-2010,
Integration Team Pattern
44
Feature
Development
Integrate
Features
All features are
implemented
and integrated
every iteration
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55. © 2009-2010,
Integration Team Pattern
Pros
Reduces complexity on Feature Teams
Forces delivery from Integration Team instead of interface and
deployment designs
Cons
Perpetuates specialized roles
Don’t always work on highest value Product Backlog items
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56. © 2009-2010,
Component Shepherd Pattern
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57. © 2009-2010,
Component Shepherd Pattern
Pros
Share more knowledge within organization to minimize platform
experience debt
Work on highest value Product Backlog items
Cons
Not always optimal as using individual knowledge
Difficult to learn multiple systems across Teams
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58. © 2009-2010,
Feature Team Pattern
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59. © 2009-2010,
Feature Team Pattern
Pros
Team owns architecture decisions
Decisions are made close to implementation concerns
Cons
May not have appropriate experience on Team
Team could get “stuck” on architecture decisions
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60. What is possible?
High quality can be attained and enables accelerated feature delivery.
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61. © 2009-2010,
A Story: Field Support Application
2000+ users access application each day
Application supports multiple perspectives and workflows
from Field Support Operations to Customer Service
Team of 5 people delivering features on existing Cold Fusion
platform implementation
Migrating to Spring/Hibernate in slices while delivering
valuable features
36 2-week Sprints, 33 production releases, and only 1 defect
found in production
So, what was the defect you say? Let me tell you…
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62. Lets wrap this up...
What should I take away from this?
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63. © 2009-2010,
Principles for Managing Software Debt
Maintain one list of work
Emphasize quality
Evolve tools and infrastructure continually
Improve system design always
Share knowledge across the organization
And most importantly, get the right people to work on your software!
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64. Thank you
Questions and Answers
54
54Thursday, October 28, 2010

65. © 2009-2010,
Chris Sterling – AgileEVM Inc.
Developer of AgileEVM ( www.AgileEVM.com ), a
project portfolio decision support tool
Technology Consultant, Agile Consultant and
Certified Scrum Trainer
Consults on software technology, Agile technical
practices, Scrum, and effective management
techniques
Innovation Games® Trained Facilitator
Open Source Developer and Consultant
Software technology, architecture, release
management, monitoring, and design consulting
for Agile Teams
55
Email: chris@agileevm.com
www.AgileEVM.com
Web: http://www.sterlingbarton.com
Blog: http://www.gettingagile.com
Follow me on Twitter: @csterwa
55Thursday, October 28, 2010