Posts Tagged ‘agile methods’

Agile Testing

February 2, 2008

As new and better software development ways are being uncovered, the following holds much value i.e.:

  1. Individuals and interactions over processes and tools.
  2. Working software over comprehensive documentation.
  3. Customer collaboration over contract negotiation.
  4. Responding to change over following a plan.

 Two key imperatives underlying these values are: 

Work Code

A general thumb of rule is that programmers are more comfortable getting on the computer and getting it to do something, than writing documentation.  Similarly, Agile believes in the Hands-On Imperative and extends it even to users.  Why?  Because, most mental activities need external resources, with different resources making us think in different ways.  And, that is why people who document or design models, think differently from those working on software.

Because, Agile projects understand that, they deliver working software (or perhaps executable proto-types) as quickly and as frequently as practical.  Development is a rapid series of functionally complete releases the user can try out.  Each release being the first chance a user’s had to think about new features, means re-work on the release is just part of the job, not a crisis. 

Open Communication

With little or no documentation, Agile projects keep everyone in synch due to increased human contact i.e. face-to-face conversation and collaboration.  XP has people programming in pairs, with most often a customer representative working most days in the bullpen with the developers.  Scrum holds daily stand-up meetings that create and preserve group understanding.  Crystal, perhaps the least dogmatic process conceivable, nevertheless insists on frequent retrospectives.  All these techniques tend to foster communication that documents cannot replace.

And, since all Agile methods want a customer to be part of the team, with a suitable customer representative on hand, one does not require a detailed requirements document.  You have a question, simply turn around and ask it!  Worried the right question won’t be asked?  Well, you can implement something and show it to your customer for a quick reaction.  Without much ado about nothing, you’ll quickly learn if you’re going off track. 

Agile Testing

These same imperatives can also underlie Agile Testing, and most obviously apply to Agile development projects.  However, they work, though less well on conventional projects, as well.

But, first abandon the idea that communication is about one party communicating with requirements and design documents, while the other comes back with test plans and bug reports.  You know full well that documents tests are based on are flawed i.e. incomplete, incorrect, and ambiguous and to be viewed only as interesting texts, partly fictional, often useful.

Agile testing communication should be all about joining in and encouraging ongoing project conversation.  Testers and developers need to sit in the same bullpen or share offices.  Testers should be made help particular developers, rather than just testing how pieces of the product work.  ‘Drop-in meetings’, short, informal discussions, etc. help in test status reports via big, public, simple-to-read charts that answer specific development questions, such as, which product parts are working well.

Communicating with the customer is as important as communicating with developers, as more often than not, the customer is trying to figure out what is needed, what they want, whether they are getting it.  And, they can only do this by testing the working code and talking to the developers and testers.  Testers should sit down with them as try out the product sample, as creating tests together is an excellent way for both to learn what matters.

Hands On helps developers improve and complete the product and value tests they can run as they develop.  While, Agile Testing may not be the answer to all projects, neither are any of the Agile Methods.  Acutally, no single approach is, but experimenting with different project styles is essential if a standardised software development practice is to be arrived at. 

Taking Agile Mainstream

January 9, 2008

This blog, perhaps, repeats what we talked about in Agile Introduction For Dummies – Part I and Agile Introduction For Dummies – Part II, but it is essential to ensure that one understands the dynamics of Agile methodology clearly.  So, here we go once again!

The past few years have seen software methodology adopting a new style and going agile!  Well knownas Agile Methods, the style is adaptive; people oriented in nature and have stirred up a whole lot of interest.  It is also seen as an antidote to bureaucracy or licence to hack. A reaction to engineering or plan driven methodologies, agile methods are an attempt at compromising between no process and too much process, providing just enough process to gain a reasonable pay-off.  As well, Agile Methods tend to be:1.       Adaptive rather than predictive.  Engineering methods mean a planned detailed software process covering a long time span and a nature that resists change.  Agile methods, however, welcome it, trying to be processes that adapt and thrive on change, even to the point of changing themselves.2.       People-oriented rather than process-oriented.  Engineering methods work at defining processes that will work for whoever uses them.  Agile methods assert a process cannot match the skills of a development team, only playing a support role in development team work. Exploration of the differences in detail makes it easier to understand what adaptive or people-centred processes are about, their benefits, drawbacks, and usefulness if used by developer or software customer. 

PREDICTIVE Vs ADAPTIVE

Separating Design and Construction

Design and construction, two fundamentally different activities show that difficult to predict design requires expensively creative people, while construction is easier to predict, and only once design is in place, can easier to predict construction begin. 

Unpredictability of Requirements

In every project, developers can be heard complaining that the problem with the particular project is that requirements are always changing.  Not surprising, as in building business software requirements, changes are the norm.  The question is what is to be done as software development is a design activity that is hard to plan for and estimate the cost for, as basic materials change rapidly and much depends on which individual people are involved resulting in unpredictability. 

Is Predictability Impossible?

Generally speaking, one cannot say predictability is not predictable.  While, it is very desirable, however letting it go does not mean reverting to uncontrollable chaos.  All one needs is a process that gives control over unpredictability, which easily explains what adaptability is all about. 

Iterations – Controlling an Unpredictable Process

So, what is the key to an unpredictable world?  Is it iterative development or frequent production of the final system working version with a sub-set of the required features?  While iterative development is short on functionality, it is otherwise faithful to the demands of the final system; hence these features should be fully integrated and carefully tested as the final delivery for best results. A far better process than traditional methods where before doing anything else, the entire process is documented, and as one knows documents can hide all sorts of flaws, as does untested code.  However, sitting in front of a system and working with it, allows these flaws to become truly apparent, both in terms of bugs and misunderstood requirements. Agile, an iterative and incremental development process is adaptive in nature and can totally deal with changes in required features.  This means fluid long term plans, as the only stable plans are short term plans made for single iterations.  AS well, iterative development also gives a firm foundation to each iteration, which means later plans can be based around it. The key question is, how long should iteration be.  Different Agile methods suggest different time frames, e.g. XP suggests iterations of one or two weeks, SCRUM suggests a month, Crystal stretches it further.  However, the tendency is to make each iteration, as short as can be got away with, as this not only provides more frequent feedback, but allows you to know where you are more often. 

Adaptive Customers

An adaptive process requires adaptive customers, since it gives them much more control over software development processes.  They, not only get to check progress made at every iteration, they can also alter the direction of software development, which often results in a much closer relationship with the software developers, a true business partnership. The customer benefits, as there are a number of advantages to using agile methods, such as, much more responsive software development and an usable, although minimal system that goes into production early on.  As well, the customer can change system capabilities according to changes in business, and is also able to learn how the system is used in reality allowing for risk control, which is indeed, a key advantage of iterative development.  Further, keeping iteration lengths small means variations can be seen in different ways. 

PUTTING PEOPLE FIRST

Another attraction of agile methods is that they put people first, since adaptive process execution is not easy task and requires a very effective team of developers i.e. effective both in quality of the individuals, as well as, team blending.  Adaptivity requires a strong team and it bodes well for agile method application to a project, since it is a well known fact that most good developers prefer an adaptive process. 

People Oriented Process Management

A people oriented process, agile process acceptance requires commitment and active involvement of all the team, as these methods like Extreme Programming (XP) requires a lot of discipline to execute, with the less disciplined Crystal approach, far more suited to a wider audience. As well, developers are required to be able to make all technical decisions, with XP getting to the heart by stating that only developers are allowed to estimate how much time it will take to do the work.  This shift in technical leadership requires developers and management to share responsibility and an equal place in project leadership.  While, management still plays a role, it also recognizes the expertise of developers. 

The Role of Business Leadership

However, technical people cannot do the whole process themselves and require guidance in terms of what a business needs, which highlights another important adaptive processes aspect i.e. close contact with business expertise. 

AGILE DEVELOPMENT

The term agile refers to a philosophy of software development which includes many specific approaches under its broad umbrella, approaches, such as, Extreme Programming, SCRUM, Lean Development, etc., each of them having their own particular approach and own ideas..

Extreme Programming (XP)

While, during the late 1990’s, Extreme Programming got the lion’s share of attention, in many ways it still does and it beings with five values (Communication, Feedback, Simplicity, Courage, and Respect).  It further elaborates these into fourteen principles, and again into twenty-four practices, placing a strong emphasis on testing.   While, all processes mention testing, not much emphasis is placed on it.  However, XP believes testing is the foundation of development and has every programmer writing tests and production code, simultaneously, which are then integrated into a continuous integration and build process, yielding a highly stable platform for future development. 

SCRUM

In the 1980’s and 1990’s, Scrum also developed as a highly iterative development methodology that concentrates on the management aspects of software development, dividing development into thirty day iterations (called ‘sprints’) and applying closer monitoring and control, by holding daily scrum meetings.  It places much less emphasis on engineering practices, with many people combining its project management approach with extreme programming engineering practices. 

CRYSTAL

The Crystal family of software development methods approaches tailored to different size teams approach.  Despite varying, all crystal approaches share common features and have the following priorities:

  • Safety (in project outcome, efficiency, habitability.
  • Frequent Delivery,
  • Reflective Improvement, and
  • Close Communication.

Lean Development

Lean movement pioneered at Toyota was an inspiration to many of early agilists, but one should be wary of the engineering separation between design and construction.  However, there are still interesting ideas to be got from the lean direction.

SHOULD YOU GO AGILE?

Using an agile method is not for everyone.  However, these methodologies are widely applicable their use should be seriously considered.  The most common methodology of code and fix often results in chaos, showing that the discipline and lightweight agile approach found missing in heavyweight methods is the better method. Start by finding projects that agile methods can be tried on, and since methods are so fundamentally people-oriented, it is important to start with a team receptive to being agile.  As well, you will also need to find someone experienced in agile methods, having learnt through making mistakes.  And, then you may find out about the many advantages of going agile! 

Agile Introduction For Dummies – Part II

January 7, 2008

This is a continuation of Agile Introduction For Dummies – Part I

While, having much in common e.g. what they value, Agile Methods also differ in practices they suggest, such as, Extreme Programming, Scrum, Crystal Methods, Feature Driven Development, Lean Development, and Dynamic Systems Development Methodology.

EXTREME PROGRAMMING

And, Extreme Programming is undoubtedly the hottest Agile Method to emerge in recent years.  XP owes much of its popularity to developers disenchanted with traditional methods and looking for something new, something extreme. The 12-rules of Extreme Programming, true to the nature of the method itself, are concise and to the point.

  • The planning game: Each iteration begins with customers, managers, and developers fleshing out, estimating, and prioritizing requirements or ‘user stories’ for the next release, capturing it in a language that everyone can understand.
  • Small releases: An initial version of the system is put into production after the first few iterations.  Subsequently, working versions are put into production anywhere from every few days to every few weeks.
  •  Metaphor: Customers, managers, and developers construct a metaphor, or set of metaphors after which to model the system.·         Simple design: Developers are urged to keep design as simple as possible, say everything once and only once.
  • Tests: Developers write acceptance tests for their code before they write the code itself, while customers write functional tests for each iteration, with tests being run at the end of each iteration.
  • Re-factoring: As developers work, the design evolves and is kept as simple as possible.
  • Pair programming: Two developers sit together at the same machine to write the code.
  • Continuous integration: Developers integrate new code into the system, as often as possible and all functional tests must be passed code integration, or else the new code is discarded.
  • Collective ownership: The code is owned by all developers, and they may make changes anywhere in the code at anytime they feel necessary.
  • On-site customer: A customer works with the development team at all times to answer questions, perform acceptance tests, and ensure that development is progressing as expected.

 SCRUM

Scrum, along with XP, is one of the more widely used Agile Methods, it is a process that accepts the development process is unpredictable and formalising the do what it takes mentality has found success with numerous independent software vendors.  Scrum projects are split into iterations (sprints) consisting of the following:

  1. Pre-sprint planning: All system work is kept in ‘release backlog’.  During pre-sprint planning, features and functionality are selected from the release backlog and placed into the ‘sprint backlog’, or a prioritized collection of tasks to be completed during the next sprint.
  2. Sprint: Upon completion of pre-sprint planning, teams are handed their sprint backlog and told to sprint to achieve their objectives.  The sprint backlog is frozen and remains unchangeable for the duration of the sprint. Team members choose the tasks they want to work on and begin development.  Short daily meetings are critical to the success of Scrum.  Scrum meetings are held every morning to enhance communication and inform customers, developers, and managers on the status of the project, identify any problems encountered, and keep the entire team focused on a common goal.
  3. Post-sprint meeting: After every sprint, a post-sprint meeting is held to analyze project progress and demonstrate the current system.

CRYSTAL METHODS

Crystal methods focus on people, inter-action, community, skills, talents, and communication as first order effects on performance.  Process remains important, but secondary.  All Crystal methods begin with a core set of roles, work products, techniques, and notations, and this initial set is expanded as the team grows or the method hardens.

FEATURE DRIVEN DEVELOPMENT

The Feature Driven Development method comprises of the following core values:

  1. Putting in place a system for building systems is necessary for successful scaling of larger projects.
  2. Putting together a simple, well-defined process that works best.
  3. Ensuring process steps are logical.
  4. Get rid of ‘Process pride’ as it keeps the real work from happening.
  5. Good processes are moved to the background to allow team members to focus on results.
  6. Short, iterative, feature-driven life cycles are considered the best.

 And, feature driven development begins by:

1.      Building a features list.

2.      Planning feature by feature.

3.      Designing by feature and building by feature.

LEAN DEVELOPMENTThe Lean Development Agile method focuses on twelve management strategies, as follows:

1.      Customer satisfaction is the highest priority.

2.      Always provide the best value for the money.

3.      Success depends on active customer participation.

4.      Every Lean Development project is a team effort.

5.      Everything is changeable.

6.      Domain is not the point, however solutions are.

7.      Complete, do not construct.

8.      An 80% solution today, instead of a 100% solution tomorrow.

9.      Minimalism is essential.

10.  Needs determine technology.

11.  Product growth is feature growth, not size growth.

12.  Never push Lean Development beyond its limits.

DYNAMIC SYSTEMS DEVELOPMENT METHOD

Dynamic Systems Development Method (DSDM) is not so much a method as it is a framework with a six stage life cycle.

  1. Pre-project: The pre-project phase establishes that the project is ready to begin, funding is available, and everything is in place to commence a successful project.
  2. Feasibility study: DSDM stresses that the feasibility study should be short, no more than a few weeks.  And along with the usual feasibility activities, this phase should determine whether DSDM is the right approach for the project.
  3. Business study: The business study phase is strongly collaborative, using a series of facilitated workshops attended by knowledgeable staff, who are quickly able to pool their know-how and gain consensus regarding development priorities. This phase results in a Business Area Definition, identifying users, markets, and business processes affected by the system.
  4. Functional model iteration: Functional model iteration aims to build on high-level requirements identified in the business study.  The DSDM framework works by building a number of proto-types based on risk, evolving these prototypes into the complete system.  This phase and design and build phases have a common process:
    • Identify what is to be produced.
    • Agree how and when to do it.
    • Create the product.
    • Check it has been correctly produced (by reviewing documents, demonstrating a proto-type or testing part of the system).
  5. Design and build iteration: The prototypes from the functional model iteration are completed, combined, and tested and a working system delivered to users.
  6. Implementation: During implementation, the system is transitioned into use by creating an Increment Review Document that discusses the state of the system.  Either the system meets all requirements and is considered complete, or there is a missing functionality (due to omission or time concerns).  If, there is still work to be done on the system, the functional model design, build, and implementation phases are repeated until the system is complete.
  7. Post-project: This phase includes normal post-project clean-up, as well as on going maintenance. And so, Agile Methods proving popular are here to stay.  As seen, there are many Agile Methods to select from, but before an organization selects and implements an Agile Method, it should decide whether it is ready to go agile or not.

Agile Introduction For Dummies – Part I

January 7, 2008

In my previous post I wrote about Waterfall vs. Agile.  This post is all about introducing Agile Methods to people who know zilch about them.

Creating a buzz in the software development community, Agile Methods have drawn their fair share of advocates and opponents, with some considering agile methods to be the best thing to happen, while others are not so kind. Agile Methods are a reaction to traditional ways of developing software and acknowledging the “need for an alternative to documentation driven, heavyweight software development processes”.  Traditional methods begin work by eliciting and documenting a ‘complete’ set of requirements, followed by architectural and high-level design, development, and inspection.  Frustrating, as fast moving industry and technology requirements ‘change at rates that swamp traditional methods’, and customers are unable to state their needs even while, they expect more from their software.  As a result, several independent Agile methods and practices have been developed, methods that are actually a collection of different techniques (or practices) that share the same values and basic principles. As the development world changed and it became more and more obvious that traditional methods did not always work as intended, new people-oriented and flexible practices became necessary to cope with the changing requirements, such as:

  • Customer satisfaction takes precedence over conforming to original plans.
  • Change happens, instead of preventing it, far better to cope and reduce the cost of change throughout the development process.
  •  Change elimination means unresponsiveness to business conditions, quite simply it can spell business failure.
  • The market demands and expects innovative, high quality software that meets its needs, and meets them sooner rather than later. Thus, a discussion of new software developments methods saw the emergence of Agile methodology with representatives of Extreme Programming (XP), SCRUM, DSDM, Adaptive Software Development, Crystal, Feature-Driven Development, Pragmatic Programming, and others convening and putting together an Agile Manifesto dedicated to uncovering better ways of developing software through valuing:
  • Individuals and interaction over process and tools:  Traditional software engineering lays too much emphasis on process, while it is already a known fact that people matter more than process.
  • Working software over comprehensive documentation: While documentation is important, building software is the ultimate goal.
  • Customer collaboration over contract negotiation: Contracts are important, however, customer collaboration is more so, and without which nothing goes well.
  • Responding to change over following a plan: Customers and users do not always know what they want at the outset of a software project, therefore it is essential they remain open to change during project execution. 

Agile Methods aim at allowing organizations to deliver quickly, change quickly and change often.  While, Agile techniques vary in practice and emphasis, they share common characteristics, including iterative development and a focus on inter-action and communication.  Maintaining regularity allows development teams adapt rapidly to changing requirements, and working in close proximity, focusing on communication, means teams can make decisions and act on them immediately, rather than wait on correspondence.  It is also important to reduce non-value adding intermediate artefacts to allow more resources to be devoted to product development for early completion. 

Agile movement is all about programmers that add maneuoverability to the process, so that an Agile project can identify and respond to changes more quickly than one using a traditional approach.  Agile Methods are not about practices used, but about recognising people to be primary drivers behind project success, coupled with intense focus on effective maneuverability.  True agility is not just a collection of practices; but also a frame of mind, and while other processes may look Agile, they do not feel Agile.

 To be continued in Part II