The Scrum community has adopted a different set of terms than the other agile methodologies. This is done on purpose to help people realize that Agile approaches are different than traditional approaches, which can help in their adoption, but it can also hinder people's understanding because some of the terminology is not only non-standard it really doesn't make much sense. Because of this I'm often asked by people that I'm coaching to convert back and forth between terms, and recently wrote a detailed article on the subject. The following summarizes the mapping:
- Daily Scrum Meeting ==> Daily Stand-up Meeting
- Product Backlog ==> Work Item List
- Scrum Master ==> Team Lead or Team Coach
- Sprint ==> Iteration or Time Box
For more details read my article Translating Scrum Terminology
which includes explanations of a wider range of Scrum terms and discussions of why some of them really are questionable. Further reading:
I just wanted to share with you the Manifesto for Software Craftsmanship
which extends the Agile Manifesto
. The Manifesto for Software Craftsmanship states:As aspiring Software Craftsmen we are raising the bar of professional software development by practicing it and helping others learn the craft. Through this work we have come to value:
- Not only working software, but also well-crafted software
- Not only responding to change, but also steadily adding value
- Not only individuals and interactions, but also a community of professionals
- Not only customer collaboration, but also productive partnerships
That is, in pursuit of the items on the left we have found the items on the right to be indispensable.
I view this manifesto as an important step in the maturation of software development. More on this in a future blog posting.[Read More
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:
When adopting agile software development
techniques across a large number of teams within your organization it is important to provide a definition for what agile software development is, in addition to criteria
for what it means to be agile. Many people will point to the four values of the Agile Manifesto
and claim that's a good definition. Well... it might be a good definition for the visionaries and early adopters among us, but for people on the right-hand side of the technology adoption chasm (the early majority, late majority and the laggards) this isn't enough. Don't get me wrong, I'm a firm believer in the agile values but I like to cast them as philosophies instead of as a definition.
At IBM Software Group, the definition of disciplined agile software delivery which we have been sharing with our customers is:Disciplined agile software delivery is an evolutionary (iterative and incremental) approach to delivery which regularly produces high quality software in a cost effective and timely manner. It is performed in a highly collaborative and self-organizing manner, with active stakeholder participation to ensure that the team understand and addresses the changing needs of its stakeholders. Disciplined agile delivery teams provide repeatable results by adopting just the right amount of ceremony for the situation which they face.
I think that this is a pretty good definition, although I have no doubt that we'll evolve it over time.
I also suspect that the agile community will never settle on a common definition for what agile is and more than likely are smart enough not to even try. ;-)Further reading:
Although it might not be obvious, and important success factor in adopting agile techniques
is to be able to determine whether a team is agile or not. The challenge that many organizations face is that many teams will claim to be agile, yet management, who often has little or no experience with agile approaches, cannot tell which claims are true and which are over zealous (I'm being polite). The following are the criteria that I suggest you look for in a disciplined agile team:1. Produce working software on a regular basis
. This is one of the 12 principles behind the Agile Manifesto
, and in my experience is a critical differentiator between the teams that are agile and those that are merely claiming it. Ideally the team should produce potentially shippable software each iteration. That doesn't mean that they'll deploy the system into production, or the marketplace, each iteration but they could if required to do so. Typically the team will deploy into a pre-production testing environment or a demo enviroment at the end of each iteration (or more often for that matter).2. Do continuous regression testing, and better yet take a Test-Driven Development (TDD) approach
. Agile developers test their work to the best of their ability, minimally doing developer regression testing via a continuous integration (CI) strategy
and better yet do developer-level TDD
. This approach enables development teams to find defects early, thereby reducing the average cost of addressing the defects, it also helps them to deliver higher quality code and to move forward safely when adding or changing functionality.3. Work closely with their stakeholders, ideally on a daily basis
. A common practice of agile teams is to have an on-site customer or product owner who prioritizes requirements and provides information on a timely manner to the team. Disciplined agile teams take it one step further and follow the practice active stakeholder participation
where the stakeholders get actively involved with modeling and sometimes even development.4. Are self-organizing within a governance framework
. Agile teams are self-organizing, which means that the people doing the work determines how the work will be done, they're not told by a manager who may not even be directly involved with the work how it will be done. In other words the team does its own planning, including scheduling and estimation. Disciplined agile teams are self governing within an effective governance framework
.5. Regularly reflect on how they work together and then act to improve on their findings
. Most agile teams hold a short meeting at the end of each iteration to reflect upon how well things are working and how they could potentially improve the way that they are working together. Sometimes this is done in a more formalized manner in the form of a retrospective
, but often it's done informally. The team then acts on one or more of their suggested improvements the next iteration. Disciplined agile teams take this one step further and measure their software process improvement (SPI) progress over time: the act of taking these measures, perhaps via a product such as Rational Self Check
, helps to keep the team on track in their SPI efforts.
I have yet to discover an ad-hoc development team which met all five criteria, and most of them rarely meet two or three.Further reading:
Again and again I've seen IT organizations suffering from what I call the "Bureaucracy is Discipline" antipattern. For example, filling out forms and reviewing documents are both bureaucratic activities, neither of which require significant skill nor discipline to accomplish. However, agile practices such as developing potentially shippable software every iteration is easy to say but requires great discipline to accomplish. Respecting the decisions of your stakeholders, particularly those pertaining to requirements prioritization, is easy to talk about but proves to require great discipline in practice (particularly when you don't agree with a decision). It's easy to talk about taking a test-driven approach to development
, but in practice it requires significant skill and discipline to actually do.
A "process smell" which indicates that your organization is suffering from this antipattern is a focus on following repeatable processes instead of focusing on repeatable results. An example of repeatable processes is following the same route to work every day regardless of driving conditions. An example of repeatable results is getting to work on time every day, but being willing to change your route as required, bicycling into work instead of driving, taking public transit, and so on. Nobody really cares how you get to work each day (the process), what they really care about is that you got to work on time (the result). Sadly, we've been told for decades now that repeatable processes are critical to our success in IT, yet when you step back and think about that's really a reflection of a bureaucratic approach. On the other hand, a focus on repeatable results is a reflection of a more disciplined approach. Interestingly, the DDJ 2008 Process Framework survey
found that given the choice that people would much rather have repeatable results over repeatable processes
when it comes to IT.
Mistaking bureaucracy for discipline, or rigour if you prefer that term, is a reflection of the cultural damage that has occurred over the years in IT organizations as the result of traditional philosophies and techniques. Unfortunately, this mistaken belief is a significant inhibitor to software process improvement (SPI) efforts, in particular agile adoption efforts
, which must be addressed if you're to be successful. Overcoming this challenge will require a significant cultural shift in some organizations, and many people (particularly the bureaucrats) will find this uncomfortable.Further reading:
I'd like to leave you with this parting thought: Bureaucracy is bureaucracy and discipline is discipline, please don't confuse the two
I'm often asked by customers for case studies of successful agile adoptions or agile projects in general. This is definitely a valid request, and yes, such case studies exist. But I'm often concerned that the people making these requests don't appreciate the implications of what they're asking for. My concerns with case studies are:
- The juicy information is rarely included. The information that you really want to find out, such as what went wrong and why it went wrong, is rarely discussed. If problems, oops I mean "challenges", are discussed at all they're typically glossed over in favor of focusing in on the positives. Although many people want to write up the juicy bits this information is invariably edited out through the company's vetting process. In short, my advice is to take case studies with a grain of salt.
- Some case studies are more fiction than fact. Although this isn't a problem with IBM case studies due to the governance efforts of my good friends in IBM's legal department (we love you folks, really) it can be an issue with some case studies.
- The case study may no longer be true today. Stuff happens. Perhaps the case study was mostly true at the time it was written, but now that time has passed problems have appeared that weren't apparent earlier, thus the effort wasn't as nearly as successful as it was written up. For example, a few years ago I ran into the manager of a team that I had read about in one case study, only to find out that once the study was published the key team members left the company to become consultants in that subject area. Having lost these people, who were all very highly skilled, his system proved to be unmaintainable by the rest of his staff who weren't so highly skilled and had to be rewritten. Over time the success story turned into an abject failure.
- Waiting for case studies puts you in the position of follower. For every case study that gets written, dozens, if not hundreds of similar efforts didn't get written up. Writing case studies is hard, takes time, and the writer seldom gets much benefit from doing so. The lag time between the project completing and the case study being published can be many, many months and sometimes years. The implication is that by the time you wait for several case studies that are similar to your situation you've pretty much lost all opportunity for competitive advantage and are now merely trying to catch up to the organizations who are clearly ahead of you (the writers of the case studies).
- What has the requester given back to the community? I often hear people lament that there isn't enough case studies, or isn't something close enough to their situation. Yet, when I ask them how many case studies they've written and the answer is usually none. If you want to get you also need to give. ;-)
So, next time you think you need a case study before making a decision, recognize that you may be paying a fairly high opportunity cost for information that is questionable at best.Further reading:
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
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
There seems to be a lot of misunderstanding around the topic of "Agile RUP", so I thought I'd put in my $0.02 on the subject. I suspect that some of the misunderstanding stems from lack of knowledge about RUP, either because the person either hasn't looked at RUP and is simply parroting the misinformation they heard from other people or because they've seen or been involved with questionable implmentations of RUP in the past. For the first problem I suggest reading "Agility and Discipline Made Easy" by Per Kroll and Bruce MacIsaac because it gives a pretty good overview of applying RUP in an Agile manner.
The second problem is a bit more challenging to overcome because of the very nature of RUP. RUP isn't a software process, it's actually a software process framework from which you instantiate software processes. Big difference. You select, and tailor where appropriate, the process elements appropriate to your situation. Unfortunately many organizations appear to have struggled with this concept. A common anti-pattern which are organizations that look at the RUP and say "there's a lot of really good stuff here" (absolutely true) and then conclude "we need to do it all" (yikes). That's the equivalent of going to a buffet and trying to eat all of the food in it, very clearly a bad dietary strategy. Just like you need to pick and choose only the food that you should eat, hopefully being mature enough to choose food that is good for you, you need to pick the appropriate process elements which are good for you. This requires significant experience and process knowledge to do effectively because software development is a complex endeavor and the best approach for one situation may be completely different for another situation. A second anti-pattern is when organizations assign their existing process engineers, who are often used to document-heavy serial processes, and ask them to tailor the RUP. It isn't surprising that they often produce a document-heavy and serial version of the RUP (at that point I would argue that it's no longer RUP).
The point is that these problems are self-inflicted, that these organizations could just as easily have chosen to instantiate the RUP in a light and effective manner, and better yet in a truly agile manner. In practice the RUP can be as agile as you want it to be, but you need to choose to work this way.
Some important observations:1. RUP socialized many of the concepts that Agile was built on. Although the concept of iterative development was around long before RUP, for many organizations RUP made the concept palatable through its mature approach (particularly when compared to some of the RAD/Spiral strategies at the time). In many organizations RUP also socialized testing throughout the entire lifecycle, delivery of working software each iteration, and collaborating closely with stakeholders throughout the project (to name but a few). These ideas seem straightfoward today, and they've been taken to even greater extremes in some cases , but back in the mid-90s this was pretty heady stuff for the vast majority of practitioners within the IT community. 2. RUP has adopted many of the "new" agile techniques. RUP is a process framework containing a wealth of IT practices, including both agile and traditional practices (and a lot in between). RUP continues to evolve, capturing industry best practices from many sources. So naturally RUP has adopted many agile concepts such as test-driven development (TDD), continuous integration, embracing change, and others. Check it out and see for yourself.3. RUP is as agile, or non-agile, as you want to make it. I've said it before and I'll say it again -- the RUP is a process framework from which you instantiate processes. You've got complete control over how agile the RUP is.4. RUP contains many of critical techniques for scaling agile. In a previous blog posting I overviewed the issues around scaling, not only is team size an issue but so is geographical distribution, regulatory compliance, application complexity, legacy systems/policies, governance, and organizational distribution.
I'm sure some people are reading this and thinking to themselves "of course this is what Scott is going to say, that's his job." Well, think what you want, but I was writing about how to take an agile approach several years before joining IBM. In fact, I believe that I'm the first to do so, writing about it in print in my Software Development column back in 2001 and more importantly in my book Agile Modeling: Effective Practices for XP and UP in 2002. And, if you go poking around the web a bit, you'll see a lot other have written about this too, including Craig Larman, Ivar Jacobson, Bob Martin, Gary Evans, Doug Rosenberg and many more.
I'd like to leave you with a sound bite: "The RUP done right is Agile. The RUP done wrong is just plain wrong."[Read More