Your project is legacy already, you just don't know it yet

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LEGACY ALREADY Better Software Firenze, 11 Nov 2013 @arkh4m ~ @mat_jack1 YOUR PROJECT IS (YOU JUST DON’T KNOW IT YET)

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WE ARE JU & MATTEO. WE ARE HAPPY SOFTWARE ENGINEERS, WORKING AT WELAIKA & CANTIERE CREATIVO HELLO

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LET’S TALK ABOUT LEGACY {

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A gift by will, especially of money or other personal property Legacy, noun

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Heritage | Eredità

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A software which is no longer mantained or supported Legacy Software

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Nightmare | Incubo

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DEVELOPERS HATE LEGACY We’re no exception.

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UNCLEAR JUST STUPID A BIG BALL OF MUD

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THE OLD CODE IS A MESS, WE NEED TO REWRITE IT “ ”

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LOVE TO WRITE NEW CODE HATE TO READ CODE WHY SO? Developers…

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IT’S HARDER TO READ CODE THAN TO WRITE IT The Fundamental Law of Software — Joel Spolsky

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IT’S MUCH HARDER TO LISTEN THAN IT IS TO SPEAK The Fundamental Law of Life

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THE OLD CODE IS A MESS, WE NEED TO REWRITE IT “ ”

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OLD SUCKS “ ”

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CODE DOESN’T RUST

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LEGACY IS GOOD

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HAS BEEN USED HAS BEEN TESTED BUGS WERE FOUND AND FIXED Legacy Code

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SOFTWARE IS USEFUL WHEN IT SOLVES PROBLEMS The Value of Software

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WHEN SOFTWARE IS USED AND IT WORKS, IT IS GOOD Good Software

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IN TIME, GOOD SOFTWARE CAN BECOME LEGACY

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BAD SOFTWARE JUST DIES

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LET’S HOPE OUR PROJECTS WILL BE “LEGACY” ONE DAY

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SO LEGACY IS COOL?

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NOT REALLY.

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SOFTWARE IS VALUABLE WHEN IT IS EASY TO CHANGE The Value of Software, Part II — Robert Martin

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LEGACY SOFTWARE IS HORRIBLY HARD TO CHANGE

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A LEGACY TALE {

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You are managing a healthy project, along with a seasoned developer.

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You are managing a healthy project, along with a seasoned developer. You fully embraced the Agile Way™ with standup sessions, sprint plannings, TDD, continuos integration, etc.

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You are managing a healthy project, along with a seasoned developer. You fully embraced the Agile Way™ with standup sessions, sprint plannings, TDD, continuos integration, etc. The developer is pushing features like crazy, the client is happy, everything’s great.

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Out of nowhere, your developer leaves your project.

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Out of nowhere, your developer leaves your project. You find two new developers, a junior and a senior. They are very excited to join your project.

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Out of nowhere, your developer leaves your project. You find two new developers, a junior and a senior. They are very excited to join your project. After a week…

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JUNIOR DEVELOPER Confessions of a

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✤ The code is too hard to understand ✤ Features can't be added that easily ✤ Tests keep breaking all the time for misterious reasons

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SENIOR DEVELOPER Confessions of a

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✤ The code quality is too low ✤ Features can't be added that easily ✤ The test architecture is horrible and needs to be re-written

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DIFFERENT PEOPLE, DIFFERENT HABITS

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Ever notice that anyone going slower than you is an idiot, but anyone going faster is a maniac? George Carlin

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EVERY DEVELOPER HAS HIS OWN STYLE, EXPERIENCE, PRIORITIES AND VALUES

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MANY OF THESE HABITS COME FROM PERSONAL FLAVOUR, WHICH CAN BE ANNOYING FOR OTHER PEOPLE, BUT NOT NECESSARILY WRONG

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ON THE OTHER HAND, THERE ARE INTRINSIC & MEASURABLE DEFECTS IN SOFTWARE

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CODE SMELL High Complexity

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CODE SMELL Code Duplication

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CODE SMELL High Churn Rate

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CODE SMELL Low Test Coverage

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RAW DATA INVISIBLE PROBLEMS

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MAKE DATA ACCESSIBLE MAKE PROBLEMS VISIBLE

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WRAP-UP {

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WE NEED WORKING SOFTWARE

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BUT IF YOU ONLY CARE ABOUT WORKING SOFTWARE, YOU LOSE FOCUS ON THE PRODUCT QUALITY

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WHAT WORKS NOW, MAY NOT WORK TOMORROW

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MAKE A HABIT OF TRACKING YOUR PROJECTS’ HEALTH

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USE AUTOMATED HASSLE-FREE TOOLS TO KEEP SMELLS UNDER CONTROL AND MAKE PROBLEMS EVIDENT