Code RetreatLemi Orhan Ergin

Agile Software Craftsman

practice to master your crafts

Agile Software Craftsman Passionate Developer and Coach Sony & GittiGidiyor/eBay

LEMİ ORHAN ERGİN

@lemiorhan

lemiorhanergin.com

@lemiorhan

like to work alone feel safe to work on confort zone

have to focus on daily work skip writing tests

cannot find time to experiment not willing to learn new practices

do not think about design focus on gettings things done

over-engineer do not refactor

Developers

have to improve their craft

Developers

is the best way how we improve our craftPracticing

How to PracticeChallenge

Repeat Feedback

again and again and again and again

How to Practice

No Pressuredo not complete the task

but master it

practicing !

mastering

Code Retreat is about

and

writing the perfect code

Code Retreat is about

learning through pairing extending your confort zone

no pressure of daily work experimenting

learning new practices thinking deeply about design

building structures simple developing whenever required

refactoring

Code Retreat is about

1 day coding 45 minutes sessions

Pair programming Test first development

Different partners on each session Different constraints

Format

Schedule

Retrospective Break

Closing Ceramony

Coding 45

105 5 5 5 5

10 10 10 10 15

45 45 45 45 45

Lunc

h

HistoryThe idea was spawned at CodeMash Conference’09 !The owners of the idea Gary Bernhardt Patrick Welsh Nayan Hajratwala Corey Haines !First was held on January 24, 2009

Corey Haineshttps://www.flickr.com/photos/charliekilo/7717370426

Global Day of Code Retreat

2000+ developers 150+ locations 20 timezones 16 hours of coding 6 continents

coderetreat.orgCoderetreat Community Network

14th of December

https://www.flickr.com/photos/stef3d/4560661663

Code generation is not important Generate code by thinking the design

Focus on naming test cases Focus on Red/Green/Refactor cycle

Why Repeating?

You are not your code Learn to go slower

Focus on being better Do not think about finishing

It’s all about practicing

Why Deleting?

Language agnostic Do not try to complete

Focus on practicing Write code than open to accept change

Follow 4 rules of simple design Delete code after each session

Have fun

Principles

SOLID Principles Law of Demeter Design Patterns

4 Rules of Simple Design

Design Guidelines

Simple DesignSimple design in one that is easy to change.We don’t know exactly what is going to need to change We’ll never be more ignorant than we are at this moment

Simple DesignTests pass

4 Rules of

“Tests pass” can be a significant factor in making changes. If you have to ask how fast your test suite should be, it should be faster

1

Simple DesignExpress Intent

4 Rules of

Paying attention to the names and how your code expresses itself is the key.

2

Simple DesignNo Duplication (DRY)

4 Rules of

It’s not about code duplication, it’s about knowledge duplication. Don’t repeat yourself. Every piece of knowledge should have one and only one representation.

3

Simple DesignSmall

4 Rules of

Has fewer classes, modules, packages. Any not-used code should be deleted. You should also check missing or duplicate abstractions. Over-extraction should also be not allowed.

4

http://blog.thecodewhisperer.com/2013/12/07/putting-an-age-old-battle-to-rest“Putting an Age-Old Battle to Rest” by Joe Rainsberger

The Simple Design Dynamo

TDDWrite exactly one new test1

2 Run the test to make sure it fails

3 Write least amount of code to make the test pass

4 Refactor to remove duplication

5 Repeat the process

Test Driven Development Test Driven Design Test First Development

Zero-player game Cellular automation system

Devised by John Horton Conway Evolution is determined by initial state

Each cell can be alive or dead

Conway’s Game of LifeProblem to solve:

Each cell has 8 neighbours and follows 3 rules

1 2 3

4

567

8

Any live cell with fewer than 2 live neighbours dies of loneliness

Rule 1

Any live cell with more than 3 live neighbours dies of overcrowding

Rule 2

Any dead cell with exactly 3 live neighbours comes to life of warmth

Rule 3

Avoid to use primitives Avoid to use conditional conditions (if, ?:, switch) Avoid to use loops (while, for) All methods return void Max 5 lines of code per method Verbs instead of nouns Ping pong programming Mute ping pong programming Swap computers Do not use mouse

Variations

ENJOYremember whatever you do do not forget to

https://www.flickr.com/photos/fraserspeirs/3394902061Joe O'Brien and Jim Weirich while doing ruby code review

sessionslet the

beginWe select 6 activities amoung the activities list after checking

TDD and pair programming experiences of the attendees. Every coderetreat has its own set of activities.

No constraints Do your best

session 1

Ping-pong pair programming

session 2

No primitives Use only immutable objects

session 3

No primitives No conditionals

Max 5 lines of code

session 4

No way to return any value Verbs instead of Nouns

session 5

Mute ping-pong

session 6

What, if anything, did you learn today? What, if anything, surprised you today?

What, if anything, will you do differently?

closing

https://leanpub.com/4rulesofsimpledesign

The only thing we truly know about software development is that we can expect changes to our system. Through concrete examples, let's explore ways to build flexible, adaptable software systems by better understanding Kent Beck's 4 Rules of Simple Design.

Book from Corey HainesPublished at LeanPub on 2014

thanks

http://www.coderetreat.orgCoderetreat Community Network

http://blog.zilverline.com/2013/12/20/facilitating-the-global-day-of-coderetreat-2013-in-amsterdamFacilitating the Global Day of Coderetreat 2013 in Amsterdam

http://www.alexbolboaca.ro/wordpress/articles/how-to-organize-a-code-retreatHow to organize a code retreat

Coderetreat Facilitator Traininghttps://vimeo.com/54519386

https://leanpub.com/4rulesofsimpledesignUnderstanding the 4 Rules of Simple Design

Lemİ orhan ergİn

Founder & Author @ agilistanbul.comlemiorhan@agilistanbul.com

@lemiorhanhttps://www.linkedin.com/in/lemiorhan

@lemiorhanhttps://twitter.com/lemiorhan

@lemiorhanhttps://github.com/lemiorhan

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agile software craftsmanagilistanbul.comTurkish blog about agile development

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