This document discusses the principles and practices of Extreme Programming (XP), an agile software development methodology. It describes XP's emphasis on communication, rapid feedback cycles, incremental changes, and automated testing. The document outlines specific XP practices related to planning, designing, testing, and coding software. It also addresses criticisms of XP and compares it to traditional waterfall development methods. Overall, the document provides an overview of XP and argues that its lightweight approach can enable better results for rapid development projects compared to lack of methodology or strict waterfall practices.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The core values of XP are communication, simplicity, feedback, and courage. Some key XP practices include pair programming, test-driven development, planning games, daily standups, continuous integration, and on-site customers. XP aims to improve software quality and responsiveness through these values and iterative practices.
The document discusses extreme programming (XP), an agile software development methodology created in the 1990s. It provides an introduction to agile methodologies and XP, describes the XP workflow and values, and discusses key XP practices such as pair programming, test-driven development, and continuous integration. The document also covers advantages and disadvantages of XP and provides an example of how XP could be applied to a programming project.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid software development and frequent delivery of working software. It emphasizes customer collaboration, small releases, and frequent testing. Key practices of XP include writing tests first, continuous integration, pair programming, and customer involvement.
The document provides an overview of Extreme Programming (XP), an agile software development process. It discusses the origins and principles of XP, including customer satisfaction, responding to changing requirements, teamwork, communication, simplicity, feedback, respect, and courage. The document outlines the major phases of XP - planning, designing, coding, testing, and listening. It compares XP to the Spiral Model and Scrum frameworks, noting the shorter iteration times of XP.
Extreme Programming (XP) is an agile software development methodology designed for small to medium teams developing software in changing environments. It focuses on close communication between developers and customers, simplicity, feedback, and courage. Key practices include planning game, small releases, pair programming, continuous testing, refactoring, and collective ownership. XP pushes established software principles like communication, simplicity, and feedback to extreme levels. It was one of the earliest agile methodologies to challenge the traditional waterfall model.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid delivery of working software, customer satisfaction, simplicity, communication, and feedback. Key practices of XP include having working software delivered frequently in small releases, writing automated tests before code, pairing programmers, continuous refactoring, and integrating code daily. The goal of XP is to improve productivity and quality through practices like test-driven development, simple design, pair programming, and frequent feedback from customers.
Agile software development and extreme Programming Fatemeh Karimi
This document discusses Agile development and eXtreme Programming (XP). It describes XP as an Agile methodology that focuses on frequent delivery of working software through practices like test-driven development, pair programming, and continuous integration. The document outlines the 12 key practices of XP like planning games, simple design, refactoring, and on-site customers. It notes advantages of XP like increased customer focus and quality, and disadvantages like potential issues with certain team members or inflexible requirements.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The key practices of XP include pair programming, unit testing, simple design, and frequent integration. The values that underlie XP are communication, simplicity, feedback, courage, and respect. Critics argue that XP may lack documentation, design practices, and cultural adoption can be challenging.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The core values of XP are communication, simplicity, feedback, and courage. Some key XP practices include pair programming, test-driven development, planning games, daily standups, continuous integration, and on-site customers. XP aims to improve software quality and responsiveness through these values and iterative practices.
The document discusses extreme programming (XP), an agile software development methodology created in the 1990s. It provides an introduction to agile methodologies and XP, describes the XP workflow and values, and discusses key XP practices such as pair programming, test-driven development, and continuous integration. The document also covers advantages and disadvantages of XP and provides an example of how XP could be applied to a programming project.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid software development and frequent delivery of working software. It emphasizes customer collaboration, small releases, and frequent testing. Key practices of XP include writing tests first, continuous integration, pair programming, and customer involvement.
The document provides an overview of Extreme Programming (XP), an agile software development process. It discusses the origins and principles of XP, including customer satisfaction, responding to changing requirements, teamwork, communication, simplicity, feedback, respect, and courage. The document outlines the major phases of XP - planning, designing, coding, testing, and listening. It compares XP to the Spiral Model and Scrum frameworks, noting the shorter iteration times of XP.
Extreme Programming (XP) is an agile software development methodology designed for small to medium teams developing software in changing environments. It focuses on close communication between developers and customers, simplicity, feedback, and courage. Key practices include planning game, small releases, pair programming, continuous testing, refactoring, and collective ownership. XP pushes established software principles like communication, simplicity, and feedback to extreme levels. It was one of the earliest agile methodologies to challenge the traditional waterfall model.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid delivery of working software, customer satisfaction, simplicity, communication, and feedback. Key practices of XP include having working software delivered frequently in small releases, writing automated tests before code, pairing programmers, continuous refactoring, and integrating code daily. The goal of XP is to improve productivity and quality through practices like test-driven development, simple design, pair programming, and frequent feedback from customers.
Agile software development and extreme Programming Fatemeh Karimi
This document discusses Agile development and eXtreme Programming (XP). It describes XP as an Agile methodology that focuses on frequent delivery of working software through practices like test-driven development, pair programming, and continuous integration. The document outlines the 12 key practices of XP like planning games, simple design, refactoring, and on-site customers. It notes advantages of XP like increased customer focus and quality, and disadvantages like potential issues with certain team members or inflexible requirements.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The key practices of XP include pair programming, unit testing, simple design, and frequent integration. The values that underlie XP are communication, simplicity, feedback, courage, and respect. Critics argue that XP may lack documentation, design practices, and cultural adoption can be challenging.
Good software engineering practices are key to building quality and in this talk we’ll have a whistle stop tour of a range of techniques that often sit under the ‘XP’ umbrella such as TDD (Test Driven Development), Pair Programming, BDD (Behaviour Driven Development) and more generally Continuous Delivery.
XP in 10 Slides::Extreme Programming revisiting. A concise introduction to XP delivered at Agile Yorkshire in January 2012. CC-by-3.0 please download, reuse and remix.
Extreme Programming (XP) is an agile software development framework that focuses on rapid software development and frequent delivery of working software. It utilizes practices like pair programming, test-driven development, continuous integration, collective code ownership and small, frequent releases. The core values of XP include communication, simplicity, feedback and courage. An XP team consists of programmers, a customer representative, a coach and utilizes roles, practices and values to develop high quality software through collaboration and rapid, adaptive responses to changing requirements.
Integrating Quick Test Pro and Hammer – Experience ReportBrett Leonard
This document summarizes Brett Leonard's presentation on integrating HP Quick Test Pro and Empirix Hammer for automated testing. It describes the challenge of needing to test telephony functionality without a budget. Brett developed a solution to invoke Hammer scripts through Quick Test Pro's command line. The solution was proven through a concept using sample scripts. Brett documented the process and integration steps to socialize the solution and help others implement it. The documentation included installation instructions, a process description, and best practices for getting support and proving innovative solutions.
Extreme Programming (XP) is a software development methodology intended to improve quality and responsiveness to changing requirements. It involves 5 activities - planning, managing, designing, coding, and testing. Planning includes writing user stories, release planning, and frequent small releases. Managing involves dedicated workspace, stand-up meetings, and measuring velocity. Design focuses on simplicity, metaphors, CRC cards, and refactoring. Coding uses pair programming, tests first, and integration testing. All code must have unit tests that pass before release.
This document provides an introduction and overview of eXtreme Programming (XP), an agile software development methodology. It discusses what XP is, its history and origins, core values and principles, practices, and components like the whole XP team. Key aspects of XP covered include pair programming, short development cycles, test-first development, simple design, frequent integration and feedback. The document aims to explain the philosophy and mechanics of the XP methodology.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The core practices of XP include: short iterative release cycles, frequent planning games, simple design, pair programming, unit testing, collective code ownership, continuous integration, on-site customers, and 40-hour work weeks. By following these practices, XP aims to deliver working software frequently in a way that is adaptable to changing requirements.
This document provides an overview of Extreme Programming (XP), a software development methodology. It discusses key XP practices like user stories, acceptance tests, release planning, refactoring, and pair programming. XP aims to improve communication, keep designs simple, provide frequent feedback through testing, and encourage courage in decision making. It emphasizes delivering working software frequently in short iterations to ensure customer needs are met.
Extreme Programming (XP) is an agile software development methodology that values adaptability over predictability. It prescribes day-to-day practices meant to embody values like communication, simplicity, feedback, and courage. XP aims to create software that is more responsive to changing customer needs through practices like pair programming, test-driven development, and frequent small releases. The XP life cycle involves short iterative planning, designing, coding, testing, and listening phases to incorporate frequent customer feedback.
Extreme Programming (XP) is an agile software development methodology that focuses on customer satisfaction, rapid and frequent delivery of working software, simplicity, communication, and feedback. It consists of 12 core practices including planning game, small releases, simple design, refactoring, testing, pair programming, collective ownership, and continuous integration. XP values principles like communication, simplicity, feedback, courage, and quality work and aims to adapt to changing requirements, encourage teamwork, and facilitate collaboration between customers and developers.
Audrys Kažukauskas - Introduction into Extreme ProgrammingAgile Lietuva
Extreme Programming might not be a silver bullet, but in software development it is almost that. Managers get all the bells and whistles you would expect from an agile process, whilst developers are equipped with a set of principles and practices, which almost inevitably improve the codebase and enable frequent delivery of quality software. In fact, many teams, which use other software development processes (Scrum, for instance) eventually end up adopting quite a few XP practices. I'll give you an introduction into XP, share my experiences and provide references to XP material for learning more about XP.
Agile Development | Agile Process ModelsAhsan Rahim
Agile Development | Agile Process Models
Here you are going to know What is Agile Development & What are Agile Process Models for the development of Software Product.
What are different types of Agile Development, steps involve in Agile Development, XP, Scrum, Traditional Process Models with full text and animated description.
Software Process Models defines a distinct set of activities, actions, tasks, milestones, and work products that are required to engineer high-quality software...
For more knowledge watch full video...
Video URL:
https://youtu.be/3Lxnn0O3xaM
YouTube Channel URL:
https://www.youtube.com/channel/UCKVvceV1RGXLz0GeesbQnVg
Google+ Page URL:
https://plus.google.com/113458574960966683976/videos?_ga=1.91477722.157526647.1466331425
My Website Link:
http://appsdisaster.blogspot.com/
If you are interested in learning more about topics like this so Please don't forget to like, share, & Subscribe to us.
This document provides an overview of Extreme Programming (XP), an agile software development methodology. It discusses XP's history and features, which include short 2-week development cycles, pair programming, test-driven development, and frequent refactoring. The core principles of XP are also examined, such as incremental planning, small releases, simple design, and sustainable pace. Various phases of the XP process are outlined, from exploration to productionizing. Requirements are captured as scenarios and prioritized by the customer. Automated testing is a key practice in XP. Both advantages like collective code ownership and disadvantages like its unsuitability for large projects are noted.
Extreme programming (xp) | David TzemachDavid Tzemach
It’s simply the best presentation that explains the agile methodology of Extreme Programming!
Overview
1. What is Extreme programming?
2. Extreme programming as an agile methodology.
3. The values of Extreme programming
4. The Activities of Extreme programming
5. The 12 core practices of Extreme programming
6. The roles of Extreme programming
Enjoy :)
Extreme Programming (XP) is an agile software development methodology that emphasizes communication, feedback, and simplicity. It consists of 12 specific practices like pair programming, planning games, small releases, and on-site customers. The goals of XP include reducing costs, shortening development timelines by 25-50%, and keeping requirements flexible through constant collaboration between developers and customers. Studies show that XP can help complete projects at a lower cost and faster pace by improving code quality, knowledge sharing, and responsiveness to changing needs.
The document discusses different types of software review techniques, including informal reviews, formal technical reviews, and sample-driven reviews. It provides details on the goals, participants, and processes involved in formal technical reviews like walkthroughs and inspections. Metrics for evaluating the effectiveness of reviews are also presented, such as defects found per hour of preparation or inspection time. Overall, the document provides an overview of best practices and considerations for conducting effective software reviews.
optimizing code in compilers using parallel genetic algorithm Fatemeh Karimi
The document discusses optimizing code using a parallel genetic algorithm approach. It begins with introductions to compiler optimization, optimization levels in GNU GCC, and the challenges of phase ordering. It then describes the methodology which uses a master-slave model to evaluate populations of optimization flag combinations in parallel. Experimental results show the parallel genetic algorithm approach improves performance over random optimization or no optimization. In conclusion, this approach is well-suited to the compiler optimization problem and showed increased performance with more processor cores.
Extreme Programming (XP) as A Popular Agile methodology.Ali Shaikh
This document provides an overview of Extreme Programming (XP), a popular agile software development methodology. It discusses the core principles and practices of XP, including rapid feedback, simplicity, incremental changes, embracing change, quality work, pair programming, collective code ownership, continuous integration, testing, refactoring, coding standards, and more. The document also outlines the values that XP is based on such as simplicity, communication, feedback, respect, and courage. It concludes that XP brings the development team together to create quality software that can adapt to changing requirements.
Periodic Table of Agile Principles and PracticesJérôme Kehrli
Recently I fell by chance on the Periodic Table of the Elements... Long time no see... Remembering my physics lessons in University, I always loved that table. I remembered spending hours understanding the layout and admiring the beauty of its natural simplicity.
So I had the idea of trying the same layout, not the same approach since both are not comparable, really only the same layout for Agile Principles and Practices.
The result is in this presentation: The Periodic Table of Agile Principles and Practices:
Good software engineering practices are key to building quality and in this talk we’ll have a whistle stop tour of a range of techniques that often sit under the ‘XP’ umbrella such as TDD (Test Driven Development), Pair Programming, BDD (Behaviour Driven Development) and more generally Continuous Delivery.
XP in 10 Slides::Extreme Programming revisiting. A concise introduction to XP delivered at Agile Yorkshire in January 2012. CC-by-3.0 please download, reuse and remix.
Extreme Programming (XP) is an agile software development framework that focuses on rapid software development and frequent delivery of working software. It utilizes practices like pair programming, test-driven development, continuous integration, collective code ownership and small, frequent releases. The core values of XP include communication, simplicity, feedback and courage. An XP team consists of programmers, a customer representative, a coach and utilizes roles, practices and values to develop high quality software through collaboration and rapid, adaptive responses to changing requirements.
Integrating Quick Test Pro and Hammer – Experience ReportBrett Leonard
This document summarizes Brett Leonard's presentation on integrating HP Quick Test Pro and Empirix Hammer for automated testing. It describes the challenge of needing to test telephony functionality without a budget. Brett developed a solution to invoke Hammer scripts through Quick Test Pro's command line. The solution was proven through a concept using sample scripts. Brett documented the process and integration steps to socialize the solution and help others implement it. The documentation included installation instructions, a process description, and best practices for getting support and proving innovative solutions.
Extreme Programming (XP) is a software development methodology intended to improve quality and responsiveness to changing requirements. It involves 5 activities - planning, managing, designing, coding, and testing. Planning includes writing user stories, release planning, and frequent small releases. Managing involves dedicated workspace, stand-up meetings, and measuring velocity. Design focuses on simplicity, metaphors, CRC cards, and refactoring. Coding uses pair programming, tests first, and integration testing. All code must have unit tests that pass before release.
This document provides an introduction and overview of eXtreme Programming (XP), an agile software development methodology. It discusses what XP is, its history and origins, core values and principles, practices, and components like the whole XP team. Key aspects of XP covered include pair programming, short development cycles, test-first development, simple design, frequent integration and feedback. The document aims to explain the philosophy and mechanics of the XP methodology.
Extreme Programming (XP) is an agile software development methodology that focuses on rapid feedback, simplicity, communication, and responsiveness to change. The core practices of XP include: short iterative release cycles, frequent planning games, simple design, pair programming, unit testing, collective code ownership, continuous integration, on-site customers, and 40-hour work weeks. By following these practices, XP aims to deliver working software frequently in a way that is adaptable to changing requirements.
This document provides an overview of Extreme Programming (XP), a software development methodology. It discusses key XP practices like user stories, acceptance tests, release planning, refactoring, and pair programming. XP aims to improve communication, keep designs simple, provide frequent feedback through testing, and encourage courage in decision making. It emphasizes delivering working software frequently in short iterations to ensure customer needs are met.
Extreme Programming (XP) is an agile software development methodology that values adaptability over predictability. It prescribes day-to-day practices meant to embody values like communication, simplicity, feedback, and courage. XP aims to create software that is more responsive to changing customer needs through practices like pair programming, test-driven development, and frequent small releases. The XP life cycle involves short iterative planning, designing, coding, testing, and listening phases to incorporate frequent customer feedback.
Extreme Programming (XP) is an agile software development methodology that focuses on customer satisfaction, rapid and frequent delivery of working software, simplicity, communication, and feedback. It consists of 12 core practices including planning game, small releases, simple design, refactoring, testing, pair programming, collective ownership, and continuous integration. XP values principles like communication, simplicity, feedback, courage, and quality work and aims to adapt to changing requirements, encourage teamwork, and facilitate collaboration between customers and developers.
Audrys Kažukauskas - Introduction into Extreme ProgrammingAgile Lietuva
Extreme Programming might not be a silver bullet, but in software development it is almost that. Managers get all the bells and whistles you would expect from an agile process, whilst developers are equipped with a set of principles and practices, which almost inevitably improve the codebase and enable frequent delivery of quality software. In fact, many teams, which use other software development processes (Scrum, for instance) eventually end up adopting quite a few XP practices. I'll give you an introduction into XP, share my experiences and provide references to XP material for learning more about XP.
Agile Development | Agile Process ModelsAhsan Rahim
Agile Development | Agile Process Models
Here you are going to know What is Agile Development & What are Agile Process Models for the development of Software Product.
What are different types of Agile Development, steps involve in Agile Development, XP, Scrum, Traditional Process Models with full text and animated description.
Software Process Models defines a distinct set of activities, actions, tasks, milestones, and work products that are required to engineer high-quality software...
For more knowledge watch full video...
Video URL:
https://youtu.be/3Lxnn0O3xaM
YouTube Channel URL:
https://www.youtube.com/channel/UCKVvceV1RGXLz0GeesbQnVg
Google+ Page URL:
https://plus.google.com/113458574960966683976/videos?_ga=1.91477722.157526647.1466331425
My Website Link:
http://appsdisaster.blogspot.com/
If you are interested in learning more about topics like this so Please don't forget to like, share, & Subscribe to us.
This document provides an overview of Extreme Programming (XP), an agile software development methodology. It discusses XP's history and features, which include short 2-week development cycles, pair programming, test-driven development, and frequent refactoring. The core principles of XP are also examined, such as incremental planning, small releases, simple design, and sustainable pace. Various phases of the XP process are outlined, from exploration to productionizing. Requirements are captured as scenarios and prioritized by the customer. Automated testing is a key practice in XP. Both advantages like collective code ownership and disadvantages like its unsuitability for large projects are noted.
Extreme programming (xp) | David TzemachDavid Tzemach
It’s simply the best presentation that explains the agile methodology of Extreme Programming!
Overview
1. What is Extreme programming?
2. Extreme programming as an agile methodology.
3. The values of Extreme programming
4. The Activities of Extreme programming
5. The 12 core practices of Extreme programming
6. The roles of Extreme programming
Enjoy :)
Extreme Programming (XP) is an agile software development methodology that emphasizes communication, feedback, and simplicity. It consists of 12 specific practices like pair programming, planning games, small releases, and on-site customers. The goals of XP include reducing costs, shortening development timelines by 25-50%, and keeping requirements flexible through constant collaboration between developers and customers. Studies show that XP can help complete projects at a lower cost and faster pace by improving code quality, knowledge sharing, and responsiveness to changing needs.
The document discusses different types of software review techniques, including informal reviews, formal technical reviews, and sample-driven reviews. It provides details on the goals, participants, and processes involved in formal technical reviews like walkthroughs and inspections. Metrics for evaluating the effectiveness of reviews are also presented, such as defects found per hour of preparation or inspection time. Overall, the document provides an overview of best practices and considerations for conducting effective software reviews.
optimizing code in compilers using parallel genetic algorithm Fatemeh Karimi
The document discusses optimizing code using a parallel genetic algorithm approach. It begins with introductions to compiler optimization, optimization levels in GNU GCC, and the challenges of phase ordering. It then describes the methodology which uses a master-slave model to evaluate populations of optimization flag combinations in parallel. Experimental results show the parallel genetic algorithm approach improves performance over random optimization or no optimization. In conclusion, this approach is well-suited to the compiler optimization problem and showed increased performance with more processor cores.
Extreme Programming (XP) as A Popular Agile methodology.Ali Shaikh
This document provides an overview of Extreme Programming (XP), a popular agile software development methodology. It discusses the core principles and practices of XP, including rapid feedback, simplicity, incremental changes, embracing change, quality work, pair programming, collective code ownership, continuous integration, testing, refactoring, coding standards, and more. The document also outlines the values that XP is based on such as simplicity, communication, feedback, respect, and courage. It concludes that XP brings the development team together to create quality software that can adapt to changing requirements.
Periodic Table of Agile Principles and PracticesJérôme Kehrli
Recently I fell by chance on the Periodic Table of the Elements... Long time no see... Remembering my physics lessons in University, I always loved that table. I remembered spending hours understanding the layout and admiring the beauty of its natural simplicity.
So I had the idea of trying the same layout, not the same approach since both are not comparable, really only the same layout for Agile Principles and Practices.
The result is in this presentation: The Periodic Table of Agile Principles and Practices:
This document discusses Boehm's top 10 principles of conventional software management and important trends in improving software economics. It also covers the three generations of software development (conventional, transition, and modern practices), comparing their characteristics. Finally, it lists and explains 10 principles of conventional software engineering and the top 10 principles of modern software management.
Extreme Programming (XP) is an agile software development methodology that advocates short development cycles, frequent code integration and testing, pair programming, and close customer collaboration. It aims to improve productivity and responsiveness to changing requirements. Key practices include test-driven development, where automated unit tests are written before code; pair programming; frequent communication between programmers and customers; and continuous integration of code changes. XP originated from Kent Beck's work on the Chrysler payroll project in the 1990s and emphasizes adapting practices like testing and code reviews "to the extreme."
The document describes the Extreme Programming (XP) model, an agile software development methodology created by Kent Beck. It discusses the key assumptions and practices of XP, including short iterative development cycles, frequent integration and testing, pair programming, and prioritizing customer feedback. The advantages are reducing costs and risks through simplicity, spreading work across the team. Disadvantages include potential lack of upfront design and measurement of quality assurance.
The document provides an overview of Extreme Programming (XP), the most widely used agile development process originally proposed by Kent Beck. It discusses the key practices of XP including planning with user stories, small iterative releases, simple design practices like CRC cards, test-driven development, pair programming, continuous integration, and collective code ownership. The document notes that XP works well for projects with dynamically changing requirements, risky projects, or small development groups of up to 100 people.
The document provides an overview of an introduction to software engineering course. It discusses the course objectives which are to learn about difficulties in software development, different software processes, designing high-quality software, and advanced software engineering methods. The course contents are then listed, covering topics like requirements engineering, software design, testing, and project management. It also discusses the software crisis and reasons for poor project outcomes like misunderstanding software as just programming and lack of engineering practices.
eXtreme Programming (XP) is an agile software development methodology that aims to improve quality and responsiveness to changing requirements. It consists of values like communication, simplicity, feedback and courage, as well as practices like planning, small releases, testing, pair programming and refactoring. XP attempts to address common software project problems like schedule slips, defects, and inability to adapt to changing business needs. It advocates short iterations, frequent integration and customer feedback to deliver working, tested software rapidly and allow requirements to evolve over time at low cost.
eXtreme Programming (XP) is an agile software development methodology that focuses on rapid software development and delivery through practices like continuous integration, pair programming, and frequent refactoring. It aims to address common software project problems like schedule slips, high defect rates, and changing requirements by having short development cycles, automated testing, and close collaboration between developers and customers. Key XP practices include planning game, small releases, simple design, testing, refactoring, pair programming, and on-site customer involvement. Adopting XP can benefit both developers through better requirements and technical empowerment, and customers through timely delivery of valuable software that can adapt to changes.
The document provides an overview of the Rational Unified Process (RUP) and Extreme Programming (XP). RUP is a configurable software development process that uses iterative development, UML modeling, and documentation of artifacts. It consists of four main phases - inception, elaboration, construction, and transition. XP is an agile methodology based on values of communication, simplicity, feedback, and courage, and practices like planning games, test-driven development, pair programming, and frequent integration.
1. The document discusses various agile development processes including Extreme Programming (XP), Scrum, Adaptive Software Development (ASD), and Dynamic Systems Development Method (DSDM).
2. It provides an overview of the key principles and activities in each process, such as planning, design, coding, and testing in XP, and speculation, collaboration, and learning phases in ASD.
3. Scrum uses an iterative process with sprints and daily stand-up meetings to frequently deliver working software increments for customer feedback, while DSDM employs feasibility and business studies prior to iterative functional modeling, design, and implementation cycles.
The document discusses the evolution of software economics and cost estimation models over three generations:
1) Conventional (1960s-1970s) used custom tools/processes and languages with underachieved goals
2) Transition (1980s-1990s) used more repeatable processes/tools and higher languages with some commercial products
3) Modern practices (2000-present) use managed processes, integrated environments and mostly commercial products.
It also examines debates on cost estimation, noting COCOMO is well-documented but data is inconsistent. A good estimate is based on a credible model, relevant experience, and well-defined risks.
The document discusses conventional software management and its challenges. It provides three key points:
1. Only 10% of software projects were delivered successfully on time and budget in the 1990s due to software development being unpredictable and management discipline being a bigger factor in success than technology.
2. The waterfall model was the conventional approach but had issues like late risk resolution, requirements-driven decomposition, and adversarial stakeholder relationships.
3. Modern practices from the 2000s onward used more repeatable processes, off-the-shelf tools, and commercial products for improved economics compared to custom approaches of the 1960-1990 period.
Extreme Programming (XP) is an agile software development framework that focuses on customer satisfaction, rapid and flexible response to change, simplicity, communication, and feedback. The core practices of XP include the planning game, simple design, metaphor, continuous testing, pair programming, collective code ownership, and continuous integration. Tests are written and automated before code is written to ensure customer requirements are met. Customers are involved throughout development providing feedback and acceptance tests. Frequent small releases are made, often multiple times per day, to get working software into customers' hands quickly.
Extreme Programming (XP), Feature Driven Development (FDD), Scrum, and Adaptive Software Development (ASD) are agile software development methods. XP focuses on close customer collaboration, short iterations, and simple designs. FDD involves developing an overall model, building a feature list, planning and designing features, and iterative building and design of features. Scrum uses short iterations called sprints to incrementally develop functionality. ASD emphasizes incremental development through speculation, collaboration, and learning cycles to balance guidance and emergence.
Effort estimation is the process of predicting the most realistic amount of effort (expressed in terms of person-hours or money) required to develop or maintain software based on incomplete, uncertain and noisy input.
Effort estimation is essential for many people and different departments in an organization.
This document provides an overview of several agile software development methodologies:
- Extreme Programming (XP) focuses on incremental planning, small releases, simple design, test-first development, refactoring, pair programming, collective ownership, continuous integration, and sustainable pace.
- Adaptive Software Development is cyclical like evolutionary models and involves speculation, collaboration, and learning phases with short iterations.
- Lean development aims to maximize customer value while minimizing waste through practices like eliminating waste, amplifying learning, and continuous improvement.
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The document discusses agile programming and proposes a new methodology. It provides an overview of existing agile methodologies like Scrum and Extreme Programming. Scrum uses short sprints to define tasks and deadlines. Extreme Programming focuses on practices like test-first development, pair programming, and continuous integration. The document notes drawbacks like an inability to support large or multi-site projects. It proposes designing a new methodology that combines the advantages of existing methods while overcoming their deficiencies.
Similar to Jun 08 - PMWT Featured Paper -Tarabykin - XP PAPER - FINAL (20)
Jun 08 - PMWT Featured Paper -Tarabykin - XP PAPER - FINAL
1. PM WORLD TODAY – FEATURED PAPER – JUNE 2008
Extreme Programming for Better Results on Software
Development Projects
By Aleksandr Tarabykin
What is Extreme Programming?
Extreme Programming (XP) is a structured agile approach to software engineering
prescribing a set of daily practices. It emphasizes the importance of communication with the
customer, communication between team members, and development of automated testing
plans over formal documentation.
XP is based on principles of rapid feedback, preferring simplicity (and rejection of
planning for the future, scalability and reusability in advance), incremental changes and
embracing the change in the requirements.
Why should I care about XP?
Researches conducted by many companies reflects improved performance, better
quality of code (lower costly errors), better customer satisfaction and team morale when XP is
implemented.
For instance, JP Morgan Chase study [4] reported that when XP is implemented, the
total amount of defects in XP environment is averagely reduced by 63%, amount of critical
defects goes down by 79% and number of features not working as designed is reduced by 38%.
At the same time, the development time is reduced by 44-47%.
In 1999, a controlled experiment run by Robert Kessler at the University of Utah
investigated the economics of pair programming. Advanced undergraduates in a Software
Engineering course participated in the experiment. One third of the class coded class projects
as they had for years – by themselves. The rest of the class completed their projects with a
collaborative partner. The results of how much time the students spent on the assignments are
shown below in Figure 1. After the initial adjustment period in the first program (the “jelling”
assignment), together the pairs only spent about 15% more time on the program than the
2. individuals [6]. Development costs certainly do not double with pair programming! Significantly,
the resulting code has about 15% fewer defects. (These results are statistically significant.)
Figure 2 shows the post-development test cases the students passed for each program
– essentially the percentage of the instructor’s test cases passed.
The initial 15% increase in code development expense is recovered in the reduction in
defects, as the following example illustrates. Let a program of 50,000 lines of code (LOC) be
developed by a group of individual programmers and by a group of collaborative programmers.
At a typical rate of 50 LOC/hour, the individuals will develop this code in 1000 hours. It will take
the pairs 15% longer or 1150 hours -- a cost of 150 hours. Based on representative statistics
reported in [6], programmers inject 100 defects per thousand lines of code. A thorough
development process removes approximately 70% of these defects. Therefore, the individuals
would be expected to have 1,500 defects remaining in their program; collaborators would have
15% less or 1,275 – 225 less defects. In some organizations, developers’ code is passed to a
test or quality assurance department, which finds and fixes many of the remaining defects.
Typically, in systems test it takes between four and 16 hours per defect. Using a fairly
conservative factor of 10 hours/defect, if testing finds these “extra” 225 defects they will spend
2,250 hours – fifteen times more than the collaborators “extra” 150 hours! If the program is sent
directly to a customer instead of a test department, pair programming is even more favorable.
Industry data reports that between 33 and 88 hours are spent on each defect found in the field.
Using a fairly conservative factor of 40 hours/defect, if the customer is plagued by these “extra”
3. 225 defects, field support will spend 9,000 hours – sixty times more than the collaborators
“extra” time!
How does it work? What are the practices of XP?
ExtremeProgramming.Org proposes this simplified definition of XP Rules and Practices
and matches them with 4 areas of Software Development Life Cycle:
a) Planning:
Figure 3. Planning workflow according to Extreme Programming.Org
- User stories are written (user requests a feature and drives development).
- Release planning creates the schedule (programmers estimate time required to develop each
user story and users choose which stories are the most important for them)
- Make frequent small releases (releases must come every 1-3 weeks)
- The Project Velocity is measured (project velocity is a sum of estimates for the tasks/stories
completed during the duration of a project)
- The project is divided into iterations (divide your project into a dozen of short iterations; keep
iteration length constant; keep iteration deadlines seriously).
- Iteration planning starts each iteration (each iteration must start with choosing user stories to
complete during the current iteration; it is against the rules to plan ahead).
- Move people around [to avoid serious knowledge loss and coding bottle necks]
- A stand-up meeting starts each day (everyone stands up in a circle to avoid long discussions)
4. - Fix XP when it breaks (follow the XP Rules to start with, but do not hesitate to change what
doesn't work)
Figure 4. Design, Development and Testing Workflow according to
ExtremeProgramming.Org
b) Designing:
- Simplicity (always do the simplest thing that could possibly work)
- Choose a system metaphor (Choose a system metaphor to keep the team on the same page
by naming classes and methods consistently)
- Use CRC cards for design sessions (Individual CRC Cards are used to represent objects. The
class of the object can be written at the top of the card, responsibilities listed down the left
side, collaborating classes are listed to the right of each responsibility)
- Create spike solutions to reduce risk (figure out answers to tough technical or design problems
early)
- No functionality is added early (Keep the system uncluttered with extra stuff you guess will be
used later. Only 10% of that extra stuff will ever get used, so you are wasting 90% of your
time)
- Refactor whenever and wherever possible (Keep your code clean and concise so it is easier
to understand, modify, and extend. Make sure everything is expressed once and only once)
5. c) Testing (comes before coding!):
- All code must have unit tests (a failure of a test gives authority to a developer to write any
code, no code can be written unless a test is prepared)
- All code must pass all unit tests before it can be released (which allows collective code
ownership and ensures new functionality doesn’t break old one)
- When a bug is found tests are created.
- Acceptance tests are run often and the score is published (Acceptance tests are black box
system tests developed from a user story; each represents some expected result)
d) Coding:
- The customer is always available (a customer must be a available to the development team at
all times)
- Code must be written to agreed standards.
- Code the unit test first.
- All production code is pair programmed (All code to be included in a production release is
created by two people working together at a single computer)
- Only one pair integrates code at a time (to keep the system consistently robust at all times, all
source code is released to the source code repository by taking turns)
- Integrate often (Developers should be integrating and releasing code into the code repository
every few hours, whenever possible)
- Use collective code ownership (Collective Code Ownership encourages everyone to contribute
new ideas to all segments of the project)
- Leave optimization till last (Make it work, make it right, then make it fast)
- No overtime (Working overtime sucks the spirit and motivation out of a team).
Is it practical enough in a rapid development world?
Most software development in the 1990s was shaped by two major influences: internally,
object-oriented programming replaced procedural programming as the programming paradigm
favored by some in the industry; externally, the rise of the Internet and the dot-com boom
emphasized speed-to-market and company-growth as competitive business factors. Rapidly-
changing requirements demanded shorter product life-cycles, and were often incompatible with
traditional methods of software development. So, XP emerged as a response to needs of
6. modern era of software development and is actually tailored towards rapid development – its
principles of simplicity, not over-designing things, not spending much time on writing formal
documentation (but spending time on communication with the user and building test/acceptance
tests), short-time releases are essence of real world requirements of modern IT industry.
Naturally XP as any other project management methodology has some managerial
overhead and requires some discipline to follow it. But it is a light-weight methodology without
other formalities than geared to the better quality of code and improved communications inside
the team and between the team and a customer and therefore can be easier adopted by a small
company which would be involved in a rapid development.
Figure 5. XP is not about loosing time on those meetings
On the other hand, as Chaos report shows us, not having any methodology is costlier
and lack of proper management and communication could lead to a project failure, as well as
customer dissatisfaction, lack of confidence, and loss of potential contracts as a result of bad
reputation which might be hard to overcome for a small company or a start-up.
7. Figure 6. Your customers would not want to be in this situation
Therefore, it’s fair to say that a method allowing to avoid no Big Design Up Front, yet still
allowing some structure and methodology into the project team sounds like an appealing and
practical solution for a RAD development type of projects.
Does the word “extreme” suggests pushing software engineers more and how
does it correlate with previous statements?
No, it doesn't. The idea was to take several proven and time-tested best practices of a
successful software companies (or projects) and bring them to the extreme level. Here are
some facts:
• the concept of writing tests first was used by NASA in 60s.
• the concept of bottom up development (from simplest blocks to complex), code refactoring
and development in iterations were introduced by Leo Brodie in his book “Thinking Forth”
published in 1984 [7]
• The ideas of reduced design time, collective code ownership, team rotation, pair
programming, face-to-face work and reducing meetings were summarized in “Constantine
on Peopleware” [8], but were obviously a summary of best practices and ideas which were
already in the IT industry.
8. Software industry and big consulting companies which can afford rigorous
following PM techniques already have a standard way of conducting a project
(Waterfall method). Isn’t strict following to its practices superior than following
XP?
XP does not replace the need of 4 stages of Project Life Cycle. In fact, each stage of
project life cycle is addressed by one or more technique or exercise of XP. XP project consists
of several iterations and each iteration has to go through its initiation, planning, execution and
closure. User stories create basis for project initiation, planning game undertaken in the
beginning of each iteration creates project plan with its scope statement, time and budget
management, acceptance tests are both parts of scope statement and once all of them are met,
are reason for project closure. By going through several iterations, a team would learn lessons
from previous iterations (and measuring project velocity is one of the mechanisms to assure
that) more likely and would be more relevant than if a team closes a big monolithic project for a
customer and probably would never have to deal with that customer again. So, learning phase
also comes faster and delivers much needed experience when it is more valuable. If we take
one step further and compare 9 areas of Project Management knowledge as defined in PMBOK,
we would see that Extreme Programming practices each contribute to several areas of
knowledge and complete set of XP addresses each area with its own lightweight approach (see
Appendix A).
Comparing Waterfall Method vs XP itself we must notice that while certain projects and
certain environments cannot avoid following the required methodology (by political reasons, or
because of the established protocols), it has several big problems in it which brought agile
techniques into existence. Big upfront costs, late testing, high level of pressure during the
integration phase were the reasons why even big companies are constantly seeking for new
ways to organize their development efforts.
Waterfall method is also considered to bear higher risk, since no integration is expected
until the end of the project. With agile development in general and XP as one of them, customer
would have a clearer picture and some working software with most desired features even if the
project would not be completed on time. A good example of this can be a story of Chrysler
Comprehensive Compensation System (C3). Chrysler was following traditional Waterfall method
and after one year the project was on the edge of its cancellation with no software at all. Then
Kent Beck was hired to fix the system in 1996 and in 1997 his team delivered a working system
9. which was actually able to pay 10000 of Chrysler employees. In 1998 Daimpler took over
Chrysler and early in 2000 the project was cancelled. This project is considered both success of
XP methodology and its failure, but the project was definitely not on track before 1996, so from
the pure mathematical point of view delivering 0 in 1 year is still less than delivering 10% of the
project in 3 years.
Another project worth mentioning is Ford’s Vehicle Cost and Profit System (VCAPS)
project where waterfall method was used for 5 years to build a system. And after 5 years of
development and as result of some hiring of new employees, some change in methodology was
started as an underground effort. The team of XPers started first with applying automated tests
which allowed reducing number of bug reports by 30% within the first 6 month and applying
collective code ownership principles and frequent iterations reduced error reports by another
10% (all happened within the first year). Such significant reduction of bugs allowed the team to
won management support to start system over. The new system with 80% of functionality
(including unit-tests) was developed in 6 months. A good example of XP strength was that when
a new requirement came to be included into both new version and old version of VCAPS, it took
3 days to incorporate new requirements into XP version (with the certainty that no old
functionality is broken due to existence of automated tests) and it took 30 days for non-XP
version to include new functionality. The project was officially cancelled before version 2 was
completed, XP version of VCAPS (v1) replaced in production non-XP version and is still in
production after 10 years with only 2 programmers left to maintain it. It is still scheduled to be
eventually replaced by another cost and profit system, but the quality of VCAPS XP v.1 made it
possible to still be there after 10 years of being in maintenance mode. Peter Foreman (VCAPS
project team member) wrote about VCAPS project - “This is a success story for XP. The goal of
XP is to have customers happy with the software, managers happy with the cost, and
developers happy to be on the project. We had all 3.”
How could Extreme Programming help us to achieve better results?
10. During Planning Phase of Software Development Life Cycle:
• Through collecting and processing user stories, a team gets important user feedback as to
which features are the most desirable and customers get an idea about how much time it
might take to implement requested feature.
• Release planning allows the team to implement the most important features first.
• Planned Iterations adds agility to the development process and allows the team to adjust to
changing requirements. Having many releases also improves software integration, quality
control and team morale.
• Measuring Project Velocity allows the team to come up with a good schedule and maintain
about the same pace of development through many iterations.
• Standup meetings save time for development.
During Design Time
• Spike Solutions allows a team to attack technical challenges early.
• No functionality can be added early – which means we keep the system uncluttered with
extra stuff you guess will be used later (of which only 10% would be actually used).
• Refactor requirement and allocating time for clean up at the end of each iteration helps us to
keep our code clean, simple and healthy.
During Implementation
• Unit Test first rule requires to focus on input/output parameters and simplest solution to pass
the test before doing any optimizations. It also creates a valuable documentation for other
developers about how to use methods of the class; and provides a feedback to
customers/project managers if the task is understood correctly by the developer.
• Collective Code Ownership improves overall quality of software, improve team flexibility and
sharing knowledge of the whole system and boosts productivity.
During testing phase
• Ensures all code is tested with Acceptance Tests
• When a new bug is found, new test must be developed
11. Did you ever applied principles of XP to your own projects and how did you benefit from
them?
Yes and no. XP is a set of principles and techniques evolving and clarifying over time
and slightly different from situation, project length, team size and team members themselves.
And so is my knowledge and application of XP, evolving with time. But as XP was built upon a
solid foundation of best practices, I also used some of the XP methods without realizing they are
part of XP. Let me tell you several stories illustrating different real situations.
Tale about “not using XP” and Swaps.
Before I would start writing about my personal experience with XP, I would like to share
my deep regret that I did not know about XP before recent. I used to work for a financial
software company and was assigned to the project of implementing Swap-contracts into our
system. I did not heard about NUnit-testing methodology at the time, so every now and then
(usually some big piece of code added) I would spend a day creating different swap-contract
scenarios and running them manually. I would estimate that at least 20% of my time was lost
because of need to test it manually and another 20% of time I would spend trying to fix the
system when new functionality break some of old one.
Although we have not embraced agile approach, our team (me included) were using
some agyle and XP techniques. One of which would be short release cycles (not as short as XP
would prescribe, but still we would be required to consistently bring small pieces of functionality
each 3 months). Most remarkably we were doing a form of remote pair programming when an
outside software consultant would be paired with an onboard software engineer taking turns in
development due to different time zones. So, we maintained a shared body of knowledge which
helped us to preserve the knowledge of every piece of code whenever either offshore or
onboard developer had to leave. The one who stays with the company would keep a very
valuable record of original product requirements, design decisions and reasons behind them
and would help a new person to get on track much faster.
12. Tale about developing mobile label printing software and how unit test saved me from
embarrassment to find the bug only at the very late stage.
Here is another recent story. I am currently developing a Mobil Label Printing software
for a warehouse vendor and decided to use some techniques of XP (I couldn’t use all of them
because the project is supposed to be just 1 month long and I have only myself in the team). I
decided (partially as a response to a criticism from my friend, experienced software engineer) to
try “tests come first” approach and started implemented different methods and classes with
delivering a unit test first. The application is really small and many methods seems to be trivial,
like implementing simplest communication protocol and parsing XML config file for parameters.
And since I am getting paid only for the final result, there is not any benefit for me to develop
anything which is not required for successful closure of this project. But I decided to stick to the
unit tests and time spent on NUnit tests saved me from 3 or 4 errors which might be more
difficult to fix once the product is sent for external testing. One of those errors would very likely
to be not noticed by the internal testing and could result in need to deploy the application to all
mobile devices and could cost me loosing the customer.
Tale about this paper.
This paper is a result of reading and researches conducted as an individual mid-term
project. The key word is project and writing the paper reflects stages of initiating, planning and
execution of it. It did not seem right to me to make a paper about XP using the Waterfall
approach. More importantly, I could not envision the big picture and start writing the project and
as a result miss the deadline.
Then I tried to think small and figured a good way to apply it to the practice. I decided to
break this paper into small stories or answers on specific queries and focus on answering one at
a time. Whenever I come up with a good question (or hear a good objection from one of my
friends, I would right it down to the end of this paper), but I wouldn’t focus on it until its time
come. I uploaded this paper often to swiki (so, whenever Jeff looses his patience with me, I
would have something delivered). I don’t know how my work would be graded yet, but I consider
applying some of XP practices here a success, as without it I spent a lot of time delivering
nothing at all.
13. Appendix A. Comparison between 9 areas of knowledge as defined in PMBOK and
XP practices
Integra-
tion
Scope Time Cost Quality Human
Resource
Communic
ations
Risk Procurement
Pair
Prog
Immed.
Peer
Support
Immediate
peer review
Cross-tem
training
Plannin’
Game
Defines
Scope
Defines
Time
Defines
Costs
Feedback
to and from
customer
Test-
Driven
Automated tests save
time and cost
Tests
insures
quality
Acceptance tests
assure proper
closing once met
Onsite
Custo-
mer
Project
Initiation
Fast
Commu-
nications
Continuous
Integration
Ensures
working
product
Working
product is
available to
customer
Reduces
risks of
failure at
the very
end
Released
products are
available for
evaluation early
Refacto-
ring
Keeps code
clean and
easy to
maintain
Small
Releases
Each
Release
is easier
to initiate
and plan
Estimates are more precise Each
release is
an entry
point to
comm..
Custome
r gets
working
product
even if
the
project is
closed
Release is easier
to evaluate and
close. Feedback
is used early.
SimpleDesign
Keeps time and costs
of development
under control
Focusing
on
simple
design
helps
team
creating
huge and
unuseful
framewor
ks
System
Meta-phor
Developers intuitively
understand code
Members of a
team can
understand and
write code faster
Improved
communicat
ions within
team
14. Collec.
Code
Owner
Internal
quality
control
Cross-team
training
Coding
Conven-
tions
Developers intuitively
understand code
Code is
consistent
with best
practices
Members of a
team can
understand and
write code faster
Sustain-
ablePace
Measured velocity gives solid
ground to estimate time to
implement each feature
Well-rested
team
performs
better and
delivers
higher
quality code
Higher job
satisfaction and
less stress
A team
has
additiona
l
resource
in case it
cannot
meet
deadline
References
During preparation of this paper I used these references, which are a great starting point
to read about XP and IT industry in general:
1. Ward Cunningham Wiki-wiki Web http://c2.com/cgi/wiki?XpFaq
2. Extreme Programming FAQ by John Brewer and Jera Design
http://www.jera.com/techinfo/xpfaq.html
3. Donovan J. Wells “Extreme Programming: A Gentle Introduction”
http://ExtremeProgramming.org
4. “Extreme Programming (XP), Six Sigma, CMMI. How they can work together JP
Morgan Chase case study” by Bob Jarvis and Stephen Gristock
http://www.sei.cmu.edu/ cmmi/ presentations/ sepg05.presentations/ jarvis-
gristock.pdf
5. History of Ford VCAPS project by team members http://c2.com/cgi/wiki?
VcapsProject
6. Laurie Williams, Robert R. Kessler, Ward Cunningham, Ron Jeffries “Strengthening
Case for Pair-Programming”
http://www.cs.utah.edu/~lwilliam/Papers/ieeeSoftware.PDF
7. Leo Brodie “Thinking Forth”
8. Larry Constantine “Constantine on Peopleware”
15. About the Author:
Aleks Tarabykin
Author
Aleks Tarabykin is a software engineer. He
completed his Bachelor and Master degrees in
Computer Science at Tomsk State University
(Russia) in 1997. He was working for TomskTelecom Corp and Contek
Ltd in Russia and moved to Boston, USA in 2001. He was working for
6 years in Eagle Investment Systems, a fast growing company
providing an enterprise-level system for Investment Accounting and
Reporting for Mutual/Hedge Funds, Brokerage and Insurance
Companies. Currently, Mr. Tarabykin attends Harvard Extension
School and works towards earning his Master Degree in Management.
He also works as an independent consultant helping several
companies to set up and successfully operate offshore software
development teams. He lives in the Greater Boston Area, MA, USA and
can be reached with questions or comments regarding this article,
ideas for new ones or business opportunities by email at
sas@tarabykin.com.