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:
The popular Agile literature can often seam naive when it comes to how Agilists work with project stakeholders:- Extreme Programming (XP) has a practice called On-Site Customer where one or more people work closely with your team to provide information and to make decisions in a timely manner.- Scrum has the role of Product Owner who is the one single person that the development team goes to for decisions about requirements. - Agile Modeling (AM) has the practice of Active Stakeholder Participation which extends On-Site Customer to get the stakeholder(s) actively involved with the modeling effort through the use of inclusive tools and techniques.
These are great strategies for small, co-located teams doing straightforward development, but they quickly fall apart at scale. This occurs for several reasons:1. Stakeholders are a diverse group. Your stakeholders include end users, business management, project funders, enterprise architects, operations staff, support staff, other system development teams, and many others. Different people have different, and often contradictory, requirements and they certainly have different priorities. It's questionable whether a single person, or a handful of persons, can adequately represent this diverse group.2. One person becomes a bottleneck. Even with a small co-located team this is a problem, let alone one that is geographically distributed or one that is very large. There's no way that a single person can be available 24/7 in a responsive manner to support distributed teams.3. It's a difficult role. The Product Owner/Customer (POC) is responsible for representing the business to the development team. They're making important decisions on a regular basis, decisions which they'll be held accountable for.4. One person becomes a serious project risk. Not only is it questionable whether a single person can fairly represent all stakeholders, even if they could what happens if you lose that person? They effectively become a single point of failure for your team.
To scale this role, consider the following strategies:1. Recognize the true scope of the POC role. Not only are they stakeholder proxies they also are a development team representative to the stakeholder community as a whole. As stakeholder proxies they'll make decisions and prioritize the work, they'll run requirements elicitation sessions, they'll negotiate priorities, and they'll put the development team in contact with stakeholders who have expertise in specific aspects of the domain. As team representatives they'll often demo the current version of the system to other stakeholders, communicate the status of the project to people, and respond to various requests for information from the stakeholders.2. Have multiple people in it. A single POC works well for small, co-located teams developing simple software. At scale you'll soon discover that you need multiple people in this role so that they don't become a bottleneck. For distributed teams it's common to see each subteam have one or more POCs who are managed by a primary/chief POC. The primary POC typically works on the coordinating team with the chief architect (I'll talk about this role in a future blog posting) and the program manager (also a topic for a future blog posting).3. Train them in business analysis skills. The person(s) in the POC role need good business analysis skills. If fact, it's common for people who were formerly BAs for traditional teams to step into the POC role, particularly with BAs who originally come from the business side of your organization. This strategy has its advantages and disadvantages. As a BA they've likely got solid business knowledge but their instincts may motivate them to take a documentation-driven approach to providing information to the development team instead of a collaboration-based approach. Be careful.4. Consider the full system development lifecycle. There's far more to the POC role than supporting the development team during Construction iterations. During "Iteration 0", the Inception phase for an Agile RUP project or the warm-up phase for an Eclipse Way project, the POC(s) will often lead the initial requirements envisioning efforts. The product backlog, or better yet your work item list, needs to come from somewhere after all. During the release iteration(s), the Transition phase for RUP or the End-Game phase for Eclipse Way, the POC(s) will focus on communicating the upcoming release to the stakeholder community, will be actively involved with any final user acceptance testing (UAT), and may even be involved with training end users.
In my January 2008 column in Dr Dobb's Journal, posted at http://www.ddj.com/architect/204801134 , I provide detailed advice about how to scale the way that you work with stakeholders on Agile projects by applying the practices of Agile Model Driven Development (AMDD). There's no magic solution, you just need to choose to organize yourself effectively. The good news is that you can easily work with stakeholders at scale.[Read More
The SEMAT vision
has recently been posted online. SEMAT is short for Software Engineering and Method and Theory (SEMAT) and I am one of several signatories and a provider of input into the effort.
There are several reasons why I'm involved with SEMAT:
- The industry clearly needs something like this. Ivar Jacobson has been writing and speaking for awhile now about how our industry behaves in a similar manner to the fashion industry
-- we lurch from one cool idea (the fashion) to another and few of us
observe that the current fashion is often just a rehash of fashion(s) from the
- The right people are involved. The SEMAT initiative has
attracted a wide range of industry experts, including both the old
guard, the new "agile guard", and people in between. Arguably we may
be short a few people, the data community isn't well represented and
I'm not sure we have the systems community covered well, but we can
address those challenges in time.
We'll achieve something. We may not pull of the entire vision, but we
are going to produce something of value and I hope that it has a
positive impact on the industry. Time will tell.
I have several thoughts about the SEMAT vision
which I'd like to share with you:
- The vision is coherent. A lot of reasoned effort went into it's development as you can see when you read it.
- It will be a challenge to identify a non-trivial kernel. Even developing a kernel language will be hard as people will often stick to their preferred terms. For example, is it an iteration, a sprint, or a time box?
- Practitioners may not notice. It will also be a significant challenge to get practitioners interested in the SEMAT effort and more importantly to leverage the material. For example, the patterns community has a long history of producing great work which for the most part is ignored by the vast majority of practitioners, with the exception of a handful of the hundreds of patterns out there. So, although SEMAT is likely to produce some great ideas, will anyone care?
- Academics may not notice. I suspect that this will be less of a problem than practitioners not noticing, but it's still a possibility.
- Position papers from many of the signatories, including myself, will soon be published at the SEMAT site. Several non-signatories have been invited to submit papers as well.
- A workshop is being held in the third week of March in Zurich. At this workshop the people who published position papers will flesh out our ideas.
- I'll blog about these things as they occur.
Modified by ScottAmbler
Over the past few months I've had several people ask me whether it makes sense to offshore agile testing, and more importantly when it makes sense to do so. So I thought I would share my thoughts on the subject:
Focus on whole team testing. The basic strategy is that agile teams should strive to do as much, if not all, of the testing themselves. We call this whole team testing. For organizations new to agile this can be daunting because they may be organized in such a way that programmers write code and then hand it over to testers for validation and verification. The implication is that organizations will need to invest in their staff so that the programmers become more well rounded and pick up testing skills (we refer this as moving from being a specialist to a generalizing specialist).
Offshore entire development teams. A common strategy for organizing geographically distributed agile teams is to have whole teams at each location. For example, if your larger team is spread across three locations - Toronto, London, and Bangalore - then each team is responsible for implementing end to end functionality. With a component-based approach the Toronto team should be fully responsible for one or more subsystems, the London team responsible for one or more subsystems, and the Bangalore team responsible for one or more subsystems. With a feature-team approach the Toronto team would implement all of the functionality, end-to-end, for a feature regardless of which subsystems that functionality affects. Agile teams typically aren't organized by job function (e.g. analysis is done in London, design and coding in Toronto, testing in Bangalore) due to the overhead of handoffs between sites, the increased risk of miscommunication due to less effective ways of communicating information, and the increased complexity of managing the work.
Adopt independent testing at scale. You may choose, or be forced to have, an independent test team that focuses on some of the more complex forms of testing. The general idea is that this team works in parallel to other subteams and tests their working builds on a regular basis. Having said that, the vast majority of the testing effort should still be done in a whole team fashion. If your team is experiencing agile scaling factors such as domain complexity or technical complexity then you may find that it makes economic sense to have an independent test team focus on forms of testing that are difficult for the subteams to address, in particular pre-production system integration testing. If your team is in a regulatory domain where independent testing is required, then you're better off to "shift left" this effort with an independent test team to reduce both cost and risk.
Offshore independent testing carefully. I would offshore independent testing only to organizations that I have a very good, long-term relationship with that have proven that they can work in a disciplined agile manner. I would also want to ensure that they have actual experience with agile independent testing AND are staffing the team with people that have that experience. A clear sign that they don't understand what is required is if the independent testing team is asking for a detailed requirements specification, an indication that they're planning on doing confirmatory testing which is better suited for whole team testing. Furthermore, I would only do this if I don't have adequate staff to do so myself AND do not have time to build up my own independent test team.
I suspect that you're going to find yourself in serious trouble if:
You do not have successful experiences with agile delivery in simpler (e.g. non-offshoring) situations first. Walk before you try to run.
You think you can save money by having agile programming done in one location and agile testing in another (the coordination costs are going to be much larger than you think)
You're offshoring testing because you're new to agile (in this situation you don't have the experience to organize let alone govern the offshored activities)
You work with a service provider where you don't have a proven track record with them when it comes to agile development (a proven track record with traditional approaches is a good start but still very risky)
In short, it can make sense to offshore agile testing in a very narrow range of situations. Be very careful.
I recently wrote an "e-book" for Internet Evolution overviewing agile software development at scale. The goal of the Agility at Scale: Become as Agile as You Can Be
ebook is to get people thinking outside of the box a bit when it comes to agile development strategies and see that they really are ready for primetime.
The Disciplined Agile Consortium
recently launched a certification programme for practitioners of Disciplined Agile Delivery (DAD)
. There are three practitioner certifications
- Disciplined Agile Yellow Belt. This beginner certification indicates to colleagues and employers that you are eager to learn Disciplined Agile Delivery (DAD) strategies that enable you to increase your skills and abilities as a software professional.
- Disciplined Agile Green Belt. This intermediate certification indicates that you are experienced at DAD and are on your way to becoming a generalizing specialist. You have the potential to be a “junior coach” under the guidance of a senior coach (someone who is likely a Disciplined Agile Black Belt).
- Disciplined Agile Black Belt. This expert certification indicates that you are a trusted expert with significant proficiency at DAD. You can coach other people in disciplined agile strategies and advise organizations in the adoption and tailoring of the DAD framework.
Differentiate yourself in the marketplace. Certification in Disciplined Agile Delivery (DAD) means something to clients and employers because it needs to be earned. Certification in DAD tells the marketplace you understand how to deliver an agile solution from end-to-end with experience in enterprise-class development.
As an aside, the Disciplined Agile Consortium is proud to have IBM Rational's Richard Knaster and Carson Holmes the president of the Global Rational User Group (GRUG) on our board of advisors.
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
It's customary to start a blog by describing the vision for it. Although this vision will undoubtedly evolve over time, it's always good to put a stake in the ground to get things started. Agile software development is clearly taking off and in my opinion is becoming the dominant development paradigm. Furthermore it appears that Agile approaches enjoy a higher success rate, providing better value for your IT investment, than do traditional approaches. Although organizations are succeeding at simpler projects with agile, many are struggling when applying Agile in more complex situations. They're finding that the "Agile rhetoric" doesn't always live up to its promises once you move into these complex situations. My goal with this blog is to share strategies for applying Agile techniques at scale.
When applying Agile strategies at scale you are likely to run into one or more of the following complexity factors:1. Geographical distribution. Is your team, including stakeholders, in different locations? Even being in different cubicles within the same building can erect barriers to communication, let alone being in different cities or even on different continents.2. Regulatory compliance. Regulations, including the Sarbanes-Oxley act, BASEL-II, and FDA statutes, to name a few, can increase the documentation and process burden on your projects. Complying to these regulations while still remaining as agile as possible can be a challenge.3. Entrenched policies, people, and processes. Most agile teams need to work within the scope of a larger organization, and that larger organization isn't always perfectly agile. Hopefully that will change in time, but we still need to get the job done right now. Your existing culture and organization can really hinder your ability to scale agile approaches, then a few "simple" changes can really help your efforts.4. Legacy systems. Although the politically correct term would be "proven assets" the reality is that it can be very difficult to leverage existing code and data sources due to quality problems. The code may not be well written, documented, or even have tests in place, yet that doesn't mean that your agile team should rewrite everything from scratch. Some legacy data sources are questionable at best, or the owners of those data sources difficult to work with, yet that doesn't given an agile team license to create yet another database.5. Organizational distribution. When your teams are made up of people working for different divisions, or if you have people from different companies (such as contractors, partners, or consultants), then your management complexity rises.6. Degree of governance. If you have one or more IT projects then you have an IT governance process in place. How formal it is, how explicit it is, and how effective it is will be up to you. IBM has been doing a lot of work in this topic over the past few years, and just recently Per Kroll and I have done some work around Lean Governance strategies. 7. Team size. Large teams will be organized differently than small teams, and they'll work differently too.8. System complexity. The more complex the system the greater the need for a viable architectural strategy. An interesting feature of the Rational Unified Process (RUP) is that it's Elaboration phase's primary goal is to prove the architecture via the creation of an end-to-end, working skeleton of the system. This risk-reduction technique is clearly a concept which Extreme Programming (XP) and Scrum teams can clearly benefit from.
It is definitely possible to scale Agile software development to meet the real-world complexities faced by modern organizations. Based on my experiences, I believe that over the next few years we'll discover that Agile scales better than traditional approaches. Many people have already discovered this, but as an industry I believe that there isn't yet sufficient evidence to state this as more than opinion. My goal with this blog is to provide advice for scaling Agile so as to increase your chances of success.
So, it looks like I have my work cut out for me. My strategy will be to address common questions which I get when working with customers and with internal IBM development teams. I have the privilege to work with a variety of software development teams worldwide, helping them to become more agile. They're all struggling with the same basic issues although don't recognize it because they're too focused on their own situation. So hopefully I'll be able to spread the word about what's actually working in practice.
I hope that you stay tuned.
- Scott[Read More
Yesterday I was involved with a workshop around agile development at scale. At one point in the conversation we started talking about the relationship between cost and quality. Some of the people in the workshop were relatively new to agile and still believed the traditional theory that to build in high quality it costs more, sometimes substantially more. This does appear to be true on traditional waterfall projects, but some people were making the mistake that this was an "natural law of IT" which also must apply to agile project teams. I naturally jumped on that idea and described how agile developers have found that writing high quality code leads to lower development costs and shorter time to value, in direct contradiction to traditional theory. A few people struggled with the idea for a bit, and one was pretty adamant that in some cases the need for very high quality does in fact lead to greater cost and time. He talked about his experiences on large-scale Rational Unified Process(RUP)
projects and in particular how some URPS (usability, reliability, performance, and supportability) requirements can increase your cost. At this point Per Kroll, co-author of Agility and Discipline Made Easy: Practices from OpenUP and RUP
, jumped into the conversation and pointed out although higher quality does lead to lower cost in most cases, using Toyota's lean approach to manufacturing as an example, that the agile community didn't completely have the relationship between quality and cost completely correct. My spidey sense told me that a learning opportunity was coming my way.
Per and I had an offline discussion about this to explore what he'd been observing in practice. In most situation it appears to be the case that higher quality does in fact lead to lower costs and shorter time for delivery, something that Per and I had observed numerous times. This happens because high quality code is much easier to understand and evolve than low quality code -- the agile community has found that it is very inexpensive to write high quality code by following practices such as continuous integration
, developer regression testing [or better yet test-driven development(TDD)
], static code analysis
, following common development conventions, and agile modeling strategies
. When you "bake in" quality from the start through applying these techniques, instead of apply traditional techniques such as reviews
and end-of-lifecycle testing (which is still valid for agile projects, but should not be your primary approach to testing) which have long feedback cycles
and therefore prove costly in practice. But, as we've learned time and again, when you find yourself in more complex situations of Agility@Scale sometimes the mainstream agile strategies fall down. For example, in situations where the regulatory compliance scaling factor is applicable, particularly regulations around protecting human life (i.e. the FDA's CFR 21 Part 11), you find that some of the URPS requirements require a greater investment in quality which can increase overall development cost and time. This is particularly true when you need to start meeting 4-nines requirements (i.e. the system needs to be available 99.99% of the time) let alone 5-nines requirements or more. The cost of thorough testing and inspection can rise substantially in these sorts of situations.
In conclusion, it does seem to be true in the majority of situations, which is what the level 1 rhetoric focuses on, that higher quality leads to lower development costs. But at scale this doesn't always seem to hold true.
PS -- Sorry for the corny title, but a couple of days ago at the Rational Software Conference I had the pleasure of interviewing Jamie Hyneman and Adam Savage from the Discovery Channel's Mythbuster's show as part of the conference keynote. They're great guys, BTW, who have had a really positive impact on motivating children to be interested in science (apparently kids like to see stuff get blown up, go figure).[Read More
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: