The document discusses the concept of software craftsmanship, which emphasizes coding skills and improving existing code through refactoring. It notes that refactoring involves changing code without changing external behavior, and is important because software needs to evolve over time. Reasons for refactoring include making future changes easier and preventing technical debt. The document provides references to influential books on refactoring, clean code, and software craftsmanship. It also lists some communities focused on this approach.

1. MANFREDI GIORDANO, 09/04/2020
SoftwareCraftsmanship
Raising the bar of professional software development[citation needed]
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2. Writingsoftwareisa(modern)craft
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3. Disclaimers
I am by no means expert in this field
I am not implying we are not already doing this
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5. MANFREDI GIORDANO, 09/04/2020
• Change in focus: industrial -> engineering -> craft
• Emphasis on coding skills and on the journey
• Takes ideas from some influential books
• The Pragmatic Programmer (Andrew Hunt, David Thomas, 2009)
• Clean Code (Robert C. Martin, 2009)
• Originates from a "fork" of the Agile movement
• As old as writing software
SoftwareCraftsmanship
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6. Craftsmanshipinpractice?
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© Ryan McGilchrist
https://flic.kr/p/53shT6

8. Code refactoring
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9. MANFREDI GIORDANO, 09/04/2020
• Changing (improving) existing code while preserving the external behaviour of the system
• No new code should be added
• Small changes at once
• Influential books:
• Refactoring: Improving the Design of Existing Code (Martin Fowler, 1999)
• Working Effectively with Legacy Code (Michael Feathers, 2004)
Whatisrefactoring?
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10. Robert C. Martin
Boy Scout Rule:
"Always leave the code in a better state
than you found it"
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11. MANFREDI GIORDANO, 09/04/2020
• Broken window theory
Whyisrefactoringneeded?
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13. MANFREDI GIORDANO, 09/04/2020
• Broken window theory
• Hard to get design & implementation right at first attempt
• Even if we do, any software will need to evolve
• It lowers the cost of future enhancements and product evolutions
• Foundation for rapid delivery – not only "the code looks cleaner"
• Never-ending journey, i.e. always room for improvement
Whyisrefactoringneeded?
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15. Refactoring in practice
• Many ways of refactoring existing code
• Rename Variable is underrated!
• Linked to both Agile and Extreme
Programming
• Technical debt management
• Test automation, test coverage,
Continuous Integration, Test-Driven
Development, pair programming, code
review
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16. Criticisms
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17. MANFREDI GIORDANO, 09/04/2020
• "If it ain't broke, don't fix it"
• What if a seemingly harmless change breaks something?
Criticisms
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19. MANFREDI GIORDANO, 09/04/2020
• "If it ain't broke, don't fix it"
• What if a seemingly harmless change breaks something?
• Never rewrite software from scratch – "the single worst strategic mistake that any software
company can make" (Joel Spolsky)
• No universally accepted definition of well-written code
• Makes feature branching more difficult
• Should we plan / allocate time for it?
• No! "Opportunistic refactoring" (Martin Fowler)
Criticisms
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20. Joshua Kerievsky
"By continuously improving the design of code, we make
it easier and easier to work with."
"If you get into the hygienic habit of refactoring
continuously, you'll find that it is easier to extend and
maintain code."
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21. MANFREDI GIORDANO, 09/04/2020
• Manifesto for Software Craftsmanship (2009)
http://manifesto.softwarecraftsmanship.org
• The Pragmatic Programmer: From Journeyman to Master (Andrew Hunt, David Thomas, 2009)
https://pragprog.com/book/tpp/the-pragmatic-programmer
• Refactoring: Improving the Design of Existing Code (Martin Fowler, 1999)
https://martinfowler.com/books/refactoring.html
• Clean Code: A Handbook of Agile Software Craftsmanship (Robert C. Martin, 2009)
http://cleancoder.com/files/cleanCodeCourse.md
• Working Effectively with Legacy Code (Michael Feathers, 2004)
https://www.oreilly.com/library/view/working-effectively-with/0131177052/
• Refactoring to Patterns (Joshua Kerievsky, 2004)
https://www.industriallogic.com/xp/refactoring/
References(1/3)
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22. MANFREDI GIORDANO, 09/04/2020
• Broken windows theory (James Q. Wilson, George L. Kelling, 1982)
https://www.theatlantic.com/ideastour/archive/windows.html
• Online catalog of refactorings (Martin Fowler)
https://www.refactoring.com/catalog/
• Scala's coding standard
https://github.com/scala/scala/blob/2.13.x/CONTRIBUTING.md#coding-standards
• Things You Should Never Do, Part I (Joel Spolski, 2000)
https://www.joelonsoftware.com/2000/04/06/things-you-should-never-do-part-i/
• OpportunisticRefactoring (Martin Fowler, 2011)
https://martinfowler.com/bliki/OpportunisticRefactoring.html
• Refactoring -- Not on the backlog! (Ron Jeffries, 2014)
https://ronjeffries.com/xprog/articles/refactoring-not-on-the-backlog//
References(2/3)
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23. MANFREDI GIORDANO, 09/04/2020
• Workflows of Refactoring (Martin Fowler, 2014)
https://martinfowler.com/articles/workflowsOfRefactoring/
• What is Software Craftsmanship? (David Max, 2016)
https://www.linkedin.com/pulse/what-software-craftsmanship-david-max/
• How we work efficiently with legacy code (2020)
https://inside.getyourguide.com/blog/2020/1/24/how-we-work-efficiently-with-legacy-code
• What makes for readable code?
https://dev.to/ben/what-makes-for-readable-code-34o7
• Boolean parameters are wrong (havoc, 2011)
https://blog.ometer.com/2011/01/20/boolean-parameters-are-wrong/
• https://en.wikipedia.org/wiki/Software_craftsmanship
• https://en.wikipedia.org/wiki/Code_refactoring
• https://en.wikipedia.org/wiki/Broken_windows_theory
References(3/3)
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24. MANFREDI GIORDANO, 09/04/2020
• London Software Craftsmanship Community (LSCC)
https://www.meetup.com/london-software-craftsmanship/
• SC London
https://sc-london.com
• French Riviera Software Craftsmanship Community
https://www.meetup.com/Riviera-SCC/
• Software Crafters Barcelona
https://softwarecrafters.barcelona
• Software Craftsmanship North America (SCNA)
https://scna.softwarecraftsmanship.org
• Many others...
Communities&Conferences
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25. "Thanks for coming to my TED talk"
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26. Bonusmemes
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https://www.reddit.com/r/
ProgrammerHumor/
comments/cpqtes/
its_always_like_this

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https://www.reddit.com/r/
ProgrammerHumor/comments/
fpd1lx/
quarantine_has_me_refactoring

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end-of-the-line/

30. Alan Key
"Most software today is very much like an Egyptian
pyramid with millions of bricks piled on top of
each other, with no structural integrity, but just
done by brute force and thousands of slaves."
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31. Gerald Weinberg
"If builders built buildings the way programmers
wrote programs, then the first woodpecker
that came along wound destroy civilisation."
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