eXtreme Programming Introdução 

Yo! • @dareenzo everywhere • tea not coffee (last 24 hours) • vim not emacs • spaces not tabs 

Aviso Legal • Portinglês • Contains highly-contagious traces of controversial ancient wisdom that might break your most core beliefs. Hang tight! • YMMV • I didn’t/won’t violate any dark-secret/pacts I have with my employers / customers / family & friends today 

porquê importa? • "Software is eating the world” — Marc Andreessen, WSJ • "Many agile projects are now, steadily and iteratively, producing crap code” — Sandro Mancuso, The Software Craftsman: Professionalism, Pragmatism, Pride • "68% dos projectos de software no mundo falham” — Standish Group CHAOS Report 

No content

–Kent Beck “XP is a lightweight methodology for small to medium sized teams developing software in the face of vague or rapidly changing requirements” 

Objectivo • Produzir software the alta qualidade de forma mais produtiva, melhorando a qualidade de vida dos desenvolvedores. • Reduzir o custo de mudanças de requisitos 

Origem Chrysler Comprehensive Compensation (C3) System 

–Kent Beck “When I first articulated XP, I had the mental image of knobs on a control board. Each knob was a practice that from experience I knew worked well. I would turn all the knobs up to 10 and see what happened. I was a little surprised to find that the whole package of practices was stable, predictable, and flexible.” porquê “eXtreme”? 

No content

Actividades Principais • Coding • Testing • Listening • Designing 

Valores • Comunicação • Simplicidade • Feedback • Coragem • Respeito 

Princípios 

Feedback rápido “A few seconds delay between the stimulus and response renders a mouse unable to learn red means food”. 

Aceitar mudanças de requisitos & mudar incrementalmente “Change is the only constant in life” — Heraclitus 

Assumir Simplicidade "Every time someone tries to end a war before it even starts, innocent people die” — Cap. América 

Responsabilidades voluntariamente aceites “With great powers comes great responsibility” — Uncle Ben 

Quality Work “Don’t leave broken Windows” — The Pragmatic Programmer “Cease dependence on mass inspection to achieve quality. Improve the process and build quality into the product in the first place” — W. Edwards Deming 

Mais princípios • Jogar para Ganhar • Adaptação local • Honestidade 

Práticas Fine Scale • Planning Game • On-site Customer • Test-First Development • Pair-Programming Shared Understanding • Simple Design • System Metaphor • Collective Code Ownership • Coding Standards Continuous Process • Continuous Integration • Refactoring • Small Releases Programmer Welfare • Sustainable Pace (40-hour work week) 

Planning Game 

• um requisito de funcionalidade descrito do o ponto de vista do utilizador em linguagem simples, que é usado para estimar, planear e validar o desenvolvimento de alguma funcionalidade • indica que funcionalidade é desejada, para quem é destinada, porquê precisa-se e os critérios de aceitação User Stories 

On-site Customer 

Test First & Refactoring 

Pair Programming 

Continuous Integration 

Small releases 

System Metaphor 

Collective Code Ownership 

40-Hour work week - Sustainable Pace 

Coding Standards PSR; PEP8; Seus próprios Coding Standards 

No content

Actores da “Whole Team” • Programador • On-site customer • Tracker • Tester • Coach 

Adoptando 1. Busque o seu maior problema 2. Resolva-o usando XP 3. Se não for mais um problema repita. 

Desafios • É difícil fazer coisas simples • É difícil aceitar que não sabemos • É difícil derrubar barreiras emocionais • É difícil convencer o cliente a permanecer conosco 

• Sob pressão, retornamos aos “maus" hábitos • Testing e Refactoring são skills por si só e devem ser aprendidos • A sociedade valoriza o indivíduo - não pares, nem equipas 

XP e Outras Metodologias 

Ideias / Tips • Fazer code Katas para aprender mais sobre testing e refactoring. Ver: http://exercism.io • Informar ao cliente que “It's developer’s (mis)understanding, not your knowledge that becomes software” • Aprender técnicas para descrever e aprender domínios mais rapidamente • Usar linters, .editorconfig & fmt tools, para nunca mais ter debates sobre espaçamento ou o posicionamento das chavetas • Em luz ao crescente número de metodologias agéis, Ivar Jacobson tem uma sugestão: “Matem todas as metodologias. Libertem as práticas” 

!= 

On XP • Extreme Programming Explained, Embrace Change by Kent Beck with Cynthia Andres - Seminal Book on XP • Extreme Programming 20 Years Later by Kent Beck • C3 Project Description on Martin Fowler's Bliki • What is eXtreme Programming by Ron Jeffries • System Metaphor Description on C2 On "agile" corruption and harm • Agile is Dead talk at GOTO Conference 2015 by Dave Thomas - "agile" manifesto signatory • The Corruption of Agile by Uncle Bob - "agile" manifesto signatory • Flaccid Scrum by Martin Fowler - "agile" manifesto signatory On Agile vs. Lean vs. … • Agile Vs. Lean: Yeah Yeah, What’s the Difference? - Abby Fletcher • Agile Versus Lean - Martin Fowler • How do the Agile, Lean and Kanban methodologies relate? - StackOverflow Question On user stories • User Stories Applied for Agile Software Development by Mike Cohn • User Stories for Agile Requirements by Mike Cohn On TDD • Growing Object Oriented Software, Guided by Tests by Steve Freeman and Nat Pryce On Refactoring • Refactoring Improving the Design of Existing Code by Martin Fowler and Kent Beck • Refactoring from Good to Great by Ben Orenstein - Aloha Ruby Conf 2012 - • RailsConf 2016 - Succession by Katrina Owen • BathRuby 2015 - Here Be Dragons by Katrina Owen • Overkill @RubyConf Portugal by Katrina Owen Dedicated sites • http://www.extremeprogramming.org - dedicated site on XP • http://agilemanifesto.org - dedicated site containing "agile" manifesto • http://exercism.io - dedicated site for practicing code katas by Katrina Owen Referências 

Go be eXtreme … Never Freeze