Contrary to popular belief, agile development teams do in fact model and yes, they even do some up front requirements and architecture modeling. Two of the best practices of Agile Modeling are Requirements Envisioning
and Architecture Envisioning
where you spend a bit of time at the beginning of the project doing enough initial modeling to get you going in the right direction. The strategy is to take advantage of modeling, which is to communicate and think things through without taking on the risks associated with detailed specifications written early in the lifecycle
. In this blog posting I will focus on requirements envisioning, in a future posting I'll cover architecture envisioning.
The goal of initial requirements envisioning is to identify the scope of your effort. You need to do just enough modeling early in the project to come to stakeholder concurrence and answer questions such as what you're going to build, roughly how long it's going to take (give a range), and roughly how much it's likely to cost (once again, give a range). If you can get the right people together in the room, which can sometimes be a logistics challenge but not one that you couldn't choose to overcome, there are very few systems (I suspect less than 5%) that you couldn't initially scope out in a few days or a week. I also suspect that most of the remaining systems could be scoped out with less than 2 weeks of modeling, and if not then I'd take that as an indication that you're taking on too large of a project. I'm not saying that you'll be able to create big detailed specifications during this period, and quite frankly given the problems associated with "Big Requirements Up Front (BRUF)
" you really don't want to, but I am saying that you could gain a pretty good understanding of what you need to do. The details, which you'll eventually need, can be elicited throughout the lifecycle when you actually need the information. A common saying in the agile community is that requirements analysis is so important for us that we do it every single day, not just during an initial phase. I'll discuss just in time (JIT) approaches to requirements modeling in a future posting.
To envision the requirements for a business application, you might want to consider creating the following models:
- High-level use cases (or user stories). The most detail that I would capture right now would be point form notes for some of the more complex use cases, but the majority just might have a name. The details are best captured on a just-in-time (JIT) basis during construction.
- User interface flow diagram. This provides an overview of screens and reports and how they're inter-related. You just need the major screens and reports for now.
- User interface sketches. You'll likely want to sketch out a few of the critical screens and reports to give your stakeholders a good gut feeling that you understand what they need. Sketches, not detailed screen specifications, are what's needed at this point in time.
- Domain model. A high-level domain model, perhaps using UML or a data modeling notation, which shows major business entities and the relationships between them, can also be incredibly valuable. Listing responsibilities, both data attributes and behaviors, can be left until later iterations.
- Process diagrams. A high-level process diagram, plus a few diagrams overviewing some of the critical processes, are likely needed to understand the business flow.
- Use-case diagram. Instead of a high-level process diagram you might want to do a high-level use case diagram instead. This is a matter of preference, I likely wouldn't do both.
- Glossary definitions. You might want to start identify key business terms now, although I wouldn't put much effort into settling on exact definitions. I've seen too many teams run aground on "analysis paralysis" because they try to define exact terminology before moving forward. Don't fall into this trap.
For small teams simple tools such as whiteboards and paper are usually sufficient for requirements envisioning. But what happens at scale? What if you're working on a large agile team, say of 50 people, 200 people (IBM has delivered software into the marketplace with agile teams of this size), or even 500 people (IBM currently has teams of this size applying agile techniques)? What if your team is distributed? Even if you have people working on different floors of the same building, let alone working from home or working in different cities or countries, then you're distributed (see my postings about distributed agile development
). Suddenly whiteboards and paper-based tools (index cards, sticky notes, ...) aren't sufficient. You're still likely to use these sorts of tools in modeling sessions with stakeholders, but because of one or more scaling factors you need to capture your requirements models electronically.
In January Theresa Kratschmer and I gave a webcast entitled Agile Requirements: Collaborative, Contextual, and Correct
which overviewed agile approaches to requirements elicitation and management, including requirements envisioning. We also showed how Rational Requirements Composer (RRC)
can be used to electronically capture critical requirements information, enabling you to address the needs of large and/or distributed agile teams, while still remaining lightweight and flexible. I suspect that you'll find the webcast to be very illuminating and RRC something that you want to take a look at (the link leads to a trial version). Of course RRC can be used in other situations as well, but that's not what I'm focused on right now.
Teams which find themselves in regulatory environments will likely need to do more than just use RRC, as might very large teams. Regulatory compliance often requires more complex requirements documentation, which in turn requires more sophisticated tools such as DOORS or Requisite Pro, and I would consider using those tools in the types of situations that warrant it. One of the things that people often struggle to understand about agile approaches is that you need to tailor your strategy to reflect the situation at handle. One process size does not fit all, so you will end up using different tools and creating different artifacts to different extents in different situations. Repeatable results, not repeatable processes
, is the rule of the day. Further reading:
Modificado por ScottAmbler
This article has been replaced by an official "Disciplined Agile Manifesto".
The text of the original article remains below.
I've recently been working with Mark Lines of UPMentors and we've had some interesting discussions around evolving the Agile Manifesto which I thought I would share here to obtain feedback. Note that this is not any sort of official position of IBM, nothing in my blog is by the way (unless explicitly stated so), nor is it some sort of devious plot to take over the agile world (although if we did have some sort of devious plot, we'd make the exact same claim). What we hope to accomplish is to put some ideas out there in the hopes of getting an interesting conversation going.
Over the past decade we’ve applied the ideas captured in the Agile Manifesto and have learned from our experiences doing so. What we’ve learned has motivated us to suggest changes to the manifesto to reflect the enterprise situations which we have applied agile and lean strategies in. We believe that the changes we’re suggesting are straightforward:
Where the original manifesto focused on software development, a term which too many people have understood to mean only software development, we suggest that it should focus on solution delivery.
Where the original focused on customers, a word that for too many people appears to imply only the end users, we suggest that it focus on the full range of stakeholders instead.
Where the original manifesto focused on development teams, we suggest that the overall IT ecosystem and its improvement be taken into consideration.
Where the original manifesto focused on the understanding of, and observations about, software development at the time there has been some very interesting work done within the lean community since then (and to be fair there was very interesting work done within that community long before the Agile Manifesto was written). We believe that the Agile Manifesto can benefit from lean principles.
Our suggested rewording of the Agile Manifesto follows, with our suggested changes in italics.
Updating the Values of the Agile Manifesto
We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value:
Individuals and interactions over processes and tools
Working solutions over comprehensive documentation
Stakeholder collaboration over contract negotiation
Responding to change over following a plan
That is, while there is value in the items on the right, we value the items on the left more.
Updating the Principles behind the Agile Manifesto
Our highest priority is to satisfy the customer through early and continuous delivery of valuable solutions.
Welcome changing requirements, even late in the solution delivery lifecycle. Agile processes harness change for the stakeholder’s competitive advantage.
Deliver working solutions frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale.
Stakeholders and developers must work together daily throughout the project.
Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.
The most efficient and effective method of conveying information to and within a delivery team is face-to-face conversation.
Quantified business value is the primary measure of progress.
Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.
Continuous attention to technical excellence and good design enhances agility.
Simplicity--the art of maximizing the amount of work not done--is essential.
The best architectures, requirements, and designs emerge from self-organizing teams.
At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly.
Leverage and evolve the assets within your organizational ecosystem, and collaborate with the people responsible for those assets to do so.
Visualize workflow to help achieve a smooth flow of delivery while keeping work in progress to a minimum.
The organizational ecosystem must evolve to reflect and enhance the efforts of agile teams, yet be sufficiently flexible to still support non-agile or hybrid teams.
We’re agile – things evolve, including manifestos. Looking forward to your feedback (add a comment).
Updates Since this Was First Published:
Test-driven development (TDD) is a common agile programming technique which has both specification and validation aspects. With TDD, you specify your software in detail on a just-in-time (JIT) basis via executable tests that are run in a regression manner to confirm that the system works to your current understanding of what your stakeholders require.
TDD is the combination of test-first development (TFD) and refactoring. With TFD, you write a single test (at either the requirements level with customer/acceptance tests or the design level with developer tests) and then you write just enough software to fulfill that test. Refactoring is a technique where you make a small change to your existing code to improve its design without changing its semantics.
TDD offers several benefits:1. It enables you to take small, safe steps during development, increasing programmer productivity.2. It increases quality. Agile developers are doing more testing, and doing it more often, than ever before. We're also fixing the problems that we find right on the spot.3. It helps to push validation activities early in the lifecycle, decreasing the average cost to fix defects (which rises exponentially the longer it takes you to detect them).4. Through single sourcing information, by treating tests as both specifications and as tests, we reduce the work required, increasing productivity.5. We leave behind valuable, up-to-date, detailed specifications for the people who come after us. Have you ever met a maintenance programmer who wouldn't want a full regression test suite for the code that they're working with?
But TDD isn't perfect. Although TDD is great at specifying code at a fine-grain level, tests simply don't scale to address higher level business process and architectural issues. Agile Model Driven Development (AMDD) enables you to scale TDD through initial envisioning of the requirements and architecture as well as just-in-time (JIT) modeling at the beginning and during construction iterations. To scale requirements-level TDD, you must recognize that customer tests are very good at specifying the details, but not so good at providing overall context. High-level business process models, conceptual domain models, and use cases are good at doing so, and these work products are often created as part of your initial requirements envisioning and iteration modeling activities. Similarly, to scale design-level TDD you must recognize that developer tests are very finely grained but once again do not provide overall context. High-level architecture sketches created during envisioning activities help set your initial technical direction. During each construction iteration, you'll do more detailed design modeling to think through critical issues before you implement them via TDD.
You also need to scale the validation aspects of TDD. TDD is in effect an approach to confirmatory testing where you validate the system to the level of your understanding of the requirements. The fundamental challenge with confirmatory testing, and hence TDD, is that it assumes that stakeholders actually know and can describe their requirements. Therefore you need to add investigative testing practices which explore issues that your stakeholders may not have thought of, such as usability issues, system integration issues, production performance issues, security issues, and a multitude of others.
For further reading, I suggest:1. My article "Introduction to TFD/TDD" at http://www.agiledata.org/essays/tdd.html which overviews TDD.2. My February 2008 column in Dr. Dobb's Journal entitled "Scaling TDD" at http://www.ddj.com/architect/205207998 which explores this issue in detail. 3. Andrew Glover's article "In pursuit of code quality: Adventures in behavior-driven development" at http://www.ibm.com/developerworks/java/library/j-cq09187/ which describes a new-and-improved take on TDD called BDD.[Read More
Modificado por ScottAmbler
An imporant step in scaling your agile strategy is to adopt a Disciplined Agile Delivery (DAD)
approach instead of one which is just focused on agile construction. One aspect of adopting a DAD approach it to mature your focus from just producing software to instead providing a solution which meets the needs of its stakeholders within the appropriate economic, cultural, and technical constraints. The fundamental observation is that as IT professionals we do far more than just develop software. Yes, this is clearly important, but in addressing the needs of our stakeholders we will often:
Provide new or upgraded hardware
Change the business/operational processes which stakeholders follow
Change the organizational structure in which our stakeholders work
Update supporting documentation
And yes, develop high-quality software
Although delivery of high-quality, working software is important it is even more important that we deliver high-quality working solutions to our stakeholders. Minimally IT professionals should have the skills and desire to produce good software, but what they really need are the skills and desire to provide good solutions. We need strong technical skills, but we also need strong "soft skills" such as user interface design and process design to name just two.
The shift to a solution-oriented focus from a software-oriented focus requires your agile teams to address some of the software-oriented prejudices which crept into the Agile Manifesto
. The people who wrote the manifesto (which I fully endorse) were for the most part software developers, consultants, and in many cases both. It is little wonder that this group would allow a bias towards software development creep into the language of their manifesto.
A common question that I keep running into with customers is whether you can take an agile approach to service oriented architecture (SOA). The quick answer is yes, because Agile is orthogonal to the implementation technologies used. You can take an agile approach developing COBOL applications running on mainframes, fat-client Java applications, multi-tier J2EE applications, and yes, even services. Granted, it's easier to do with some technologies than others, either because of the nature of the technology or because of the supporting tools.
The long answer is "yes, but". You don't adopt an SOA approach for the sheer joy of doing so, instead you very likely want to improve the level of reuse within your organization. To succeed at SOA-driven reuse you need an enterprise focus, something that doesn't appear to be very common on many agile teams. Therein lies the challenge. Several strategies for improving your chances with Agile SOA, and SOA in general, follows:1. Invest in some initial enterprise architecture modeling. You don't need to identify all of the details up front, that would take too long and actually put the effort at risk, but you do need to set a starting point to guide development teams. Identifying the technical architecture is critical, and identifying a few basic services which would provide immediate business value to one or more teams is critical. Involve people from several application project teams to ensure that you get a wide range of input. See http://www.agiledata.org/essays/enterpriseArchitecture.html for a streamlined approach to enterprise architecture modeling. Creating big, detailed models often proves to be a waste of time because development teams are rarely motivated to read mounds of documentation.2. Build out the initial infrastructure on a real application development project. This proves that your SOA strategy actually works and puts the technical foundation in place for future teams. During this period you'll be tempted to try to support several development teams, which is feasible but dramatically increases your risk. It's also tempting to focus simply on getting the infrastructure in place without delivering any business functionality, but this risks producing an ivory-tower architecture that nobody is interested in.3. Spread the service architects out onto application development teams. The people that formulated and then proved your SOA should be actively involved on the development teams that are working with it to ensure that the teams use it appropriately and to ensure that the architects get concrete feedback which they can use to evolve the architecture. When working on agile teams, these people will need to work in a collaborative and evolutionary approach just like other team members.4. Fund reuse separately. I've lost track of the number of organizations that I've run into that fail at reuse because their development teams never have the resources to develop reusable assets. That's simply the nature of the beast -- project teams will always be more interested in addressing their own specific requirements than they are in investing the time and effort to make something reusable. The real problem here is that you expect them to act differently. A better strategy is to have a separate reuse engineering team that has the resources to monitor existing projects to look for potentially reusable assets. When they find said assets this team does the work to harvest the asset, to reengineer it to make it reusable, and then to integrate back into the original source project. The goal is to make it as painless as possible to produce reusable assets such as services. If you expect project teams to do this work out of the goodness of their hearts then you're effectively punishing them when they do the right thing. That's not a very good governance strategy, IMHO.5. The reuse team now owns the asset. Any reusable asset, including services, will need to be maintained, evolved over time, and supported. This isn't free nor is it viable for project teams to do so.
If you're interested, I provide agile strategies for both enterprise architecture and strategic reuse in the book "Enterprise Unified Process". Although written under the assumption that you're taking a RUP-based approach to development, the reality is that the EUP can extend any evolutionary/agile software development process so that it addresses the larger-scale needs of modern IT organizations.
- Scott[Read More
- Does the team regularly produce value for their stakeholders?
- Does the team validate its own work to the best of its ability?
- Are stakeholders actively involved?
- Is the team self organizing?
- Does the team strive to improve their process?
Some interesting results include:
94% of teams which are claiming to be agile are providing value to stakeholders on a regular basis.
87% of teams which are claiming to be agile are validating their own work.
95% of teams which are claiming to be agile are working closely with stakeholders.
56% of teams which are claiming to be agile are self organizing.
88% of teams which are claiming to be agile are improving the process that they follow throughout the lifecycle.
Teams which are claiming to be agile often aren't. 53% of "agile teams" meet the five criteria, although 72% meet all but the self-organization criteria.
Teams which are moving towards agile but aren't there yet are reasonably close. 39% of those teams meet all five criteria and 63% meet all but self-organization.
I believe that there are several important implications:
- Whenever someone claims to be on an agile team you may want to explore that claim a bit deeper.
The low level of self organization may be an indicator of cultural challenges with organizations in that their project managers aren't giving up sufficient control. The Agility at Scale survey
in November 2009 found that 59% of respondents who indicated that their organization hadn't adopted agile techniques yet that a rigid culture was hampering their efforts. The IT Governance and Project Management
survey in July 2009 discovered that "questionable behaviors", many of which were ethically questionable (I'm being polite), were far too common within IT project management.
Although "agile teams" may not be as agile as they claim, they're still doing better than traditional V-model teams, as revealed (again) by the 2010 IT Project Success
If there was some sort of consensus within the agile community as to the criteria for determining whether a team is agile, I highly suspect that the agileness ratings would increase over time. What gets measured often improves.
However, how agile you are isn't anywhere near as important as getting better at what you're doing. So perhaps I'm barking up the wrong tree on this issue. ;-)
Just like there are 5Ps of marketing, there are also “5 Ps” of IT:
- People. People and the way they work together have a greater effect on the outcomes of a project than the processes they’re following or the products (tools and technologies) that they’re using. People issues include having visible executive sponsorship, building an environment of trust, empowering staff, focusing on leadership as well as management, recognizing that the primary gating factor when improving processes is people’s ability to absorb change, and promoting a cross-discipline strategy at both the team and individual levels.
- Principles/philosophies. We’ve found both internally within IBM as well as with many of our customers that there is a need to define a common set of principles to provide a consistent foundation to enable effective teamwork and continuous process improvement. These principles help to guide people’s decisions when their processes and practices don’t directly address the situation which they find themselves in.
- Practices/patterns. A practice is a self-contained, deployable component of a process. You might find the IBM Practices interesting.
- Products. This includes the technologies – such as databases, application servers, networks, and client platforms – and tools such as integrated development environments, testing tools, and project planning tools used to create solutions for stakeholders.
- Processes. The previous 4Ps do not exist in a vacuum, we need some sort of glue to help piece all of this together. Minimally this glue is a lifecycle although more often than not it is a full process or method.
My experience is that to be successful at software process improvement (SPI)
across your entire IT department that you must address these 5Ps. How you address each issue, and to what extent, will vary based on your situation.
There is a distinct rhythm, or cadence, at different levels of the agile process. We call this the agile 3C rhythm, for coordinate, collaborate, and conclude (which is sometimes called stabilize). The agile 3C rhythm occurs at three levels in Disciplined Agile Delivery (DAD):
- Day. A typical day begins with a short coordination meeting, called a Scrum meeting in the Scrum method. After the daily coordination meeting the team collaborates throughout most of the day to perform their work. The day concludes with a working build, hopefully you had several working builds throughout the day, which depending on your situation may require a bit of stabilization work to achieve.
- Iteration. DAD construction iterations begin with an iteration planning session (coordinate) where the team identifies a detailed task list of what needs to be done that iteration. Note that iteration modeling is often part of this effort. Throughout the iteration they collaborate to perform the implementation work. They conclude the iteration by producing a potentially consumable solution, a demo of that solution to key stakeholders, and a retrospective to identify potential improvements in the way that they work.
- Release. The DAD lifecycle calls out three explicit phases - Inception, Construction, and Transition – which map directly to coordinate, collaborate, and conclude respectfully.
The agile 3C rhythm is similar conceptually to Deming’s Plan, Do, Check, Act (PDCA) cycle:
- Coordinate maps to plan
- Collaborate maps to do
- Conclude maps to check and act
My January 2010 DDJ Agile Update, Tragic Mistakes When Adopting Test Driven Development (TDD)
, is now online. In the article I summarize what I consider to be common, and tragic, mistakes that I'm seeing organizations make when they attempt to adopt TDD.
These mistakes include:
The article also goes into potential benefits of TDD as well as potential challenges that you're face when adopting it.
When you are first adopting agile techniques in your organization a common strategy is to run one or more pilot projects. When organizing these projects you typically do as much as you can to make them successful, such as finding:
- Projects where the stakeholders are willing to actively work with you.
- IT people who are flexible, willing to try new things, and willing to collaborate with one another.
- IT people who are generalizing specialists, or at least willing to become so.
- Finding a project which is of medium complexity (therefore it's "real" in the sense that it's significant to your organization) but not one where it can make or break your organization (therefore it's safe to experiment with).
In North America we refer to this as "cherry picking" because you're picking the cherry/best situation that you can find.
- Being agile may not have been the primary determinant of success. You set up an environment where you have a good relationship with your stakeholders, where you have good people who want to work together, and the project is challenging but not impossible. Oh, and by the way you adopted a few agile techniques as well. Sounds to me that situation you could have adopted a few not-so-agile techniques instead and still succeed. Although my various project success surveys, see my IT surveys page for details, have shown time and again that agile project teams are more successful than traditional project teams I haven't been able to tease out (yet) whether this success is attributable to agile or just attributable to improved project initiation efforts.
- When adopting agile/lean widely across your organization, you can't cherry pick any more. For the past few years I've been working with IT organizations that are in the process of adopting agile/lean strategies across their entire organization, not just across a few pilot projects. What these organizations are finding is that they need to find ways to adopt agile where the business isn't as willing to work with IT, where some of the people aren't so flexible or collaborative, where some of the people are narrowly specialized and not as willing to expand their skills, or where the project exhibits scaling factors which motivates you to tailor your agile approach. It's harder to succeed with agile in these situations because they're not as "cherry" as what you've experienced previously. Luckily, if you've been successful previously then you now have some agile experienced people, you have successes to reference, and you've likely overcome some problems even in the cherry situations which you have learned from. So, your cherry successes will hopefully improve your ability to succeed even in "non cherry" situations.
- You need to work smarter, not harder. If the source of your success was actually from improved project initiation practices and not from agile, then recognize that and act accordingly. Realistically part of your success was from that and part was from agile, and the organizations that adopt a measured improvement approach potentially have the data to determine which practices lead to success and which didn't. Without the metrics you're effectively flying blind when it comes to deciding how to improve. There is clearly a mandate for smarter work practices within IT, within your organization as a whole for that matter.
If you want to gain more insight into some of the issues that you'll face when adopting agile across your organization, I suspect that you'll find my recent paper Scaling Agile: An Executive Guide
to be interesting. I've got a more detailed paper in the works, so stay tuned to this blog.