JaikusI have a great class in school called Agile Methods, but while our teacher keeps the lessons interesting by letting us discuss a lot, I find learning about agile development really inspirational when I get the opportunity to hear about actual agile development projects from real-life practitioners. I’ve had two such opportunities recently and have met Obie Fernandez, a Rails and agile practitioner from ThoughtWorks, and Ole Jepsen, freelance agile consultant and co founder of Agile Project Leadership Network.
When Obie Fernandez was in Denmark to speak at JAOO, he also met up with a bunch of us from Copenhagen Ruby Brigade at a café in central Copenhagen. While most of the evening was spent completely relaxed just talking, Obie also gave his presentation from RailsConf Chicago, which I missed when I was there - glad I got the chance to hear it in my own hometown.
The presentation was mainly a collection of case stories about projects, where ThoughtWorks has successfully used Ruby on Rails and agile development, with a lot of good points mixed in. To be honest, I can’t recount too many of these points, since Jesper Rønn-Jensen kept buying rounds of drinks to everyone and it was very late in the evening, but I think most of what he said related to Rails can be found in his own summary.
I don’t think the actual presentation material can be found online, since it contains information about clients that’s not 100 % cleared, and it’s a pity, since a lot of what I got out the presentation was from seeing the images of real developers working on real agile development. When I read texts by Kent Beck, Jim Highsmith or some of the other agile gurus, I keep thinking that it sounds almost to good to be true. That no one could actually be doing this stuff for real, because it is just so wonderfully different from how we normally develop software. That’s why it’s nice to see images of people pair programming or having stand-up meetings, while stories on post-its hangs on the whiteboard in the background - people are doing this!
Now, two valuable things I do remember Obie saying, are that:
- The only really good way to do pair programming, is have a setup with one computer, two mirrored screens and two sets of keyboards and mice that works simultaneously. This way none of the two developers has to sit and twist their neck to see the screen, they can select their own distance to each other and most importantly; they can switch between the coder and observer roles instantaneously. (This later made me think of how ironic the image on the front page of www.pairprogramming.com is.)
- Traditional unit testing is not a very good fit for many Rails-applications, at least not if they are basically just CRUD-applications without any advanced business logic. This is due to the fact that ActiveRecord - which does the actual crudding - is already thoroughly tested, and that mainly controllers and user interface is added. For this reason, Obie recommended Selenium as the way to test your application, or - better yet - as a way to do test driven development. Selenium allows you test your user interface and application flow in an automated way through your browser, using JavaScript to control the tests.
Ole Jepsen, a Danish expert in agile development (which I don’t have a picture of, so I put myself in instead - just imagine that I’m talking notes while Ole is talking), gave a lesson at my Agile Methods class in a very agile way. After a short introduction of himself and his view on development, he asked us - the students - to come up with subjects about agile development we wanted him talk about. Then each of use got three votes, and the subjects where prioritized after number of votes. “These are our stories as you - the customers - has prioritized them, and I - the supplier - will try do as many of them in this time box as possible, starting out with the most important.” Ole said. Although I have pretty comprehensive notes, I will only dig into what I found was Ole’s most important points:
Pitfalls of agile development in practice
Just like waterfall methods doesn’t work like the text books say they will (at all!), agile methods of course also have their problems and pitfalls when you take them out of (say) Kent Beck’s comfortable descriptions and into the Real WorldTM. Ole had an example from a big Danish telecommunication company, where a project which had failed several times, switched to use agile methods (”it has to hurt before they go agile!” was another of Ole’s points) - but not without problems:
- The customer (that is; the user of the system being developed) and the developers do not automatically communicate well, just because you put them in the same room. In this project, the customer and the lead architect held long meetings where customer explained the problem domain. Then the architect would spend two days writing Word documents and afterwards show them to the customer (which was in the same room), asking: “Is this right?”, and would get the answer: “No no, that’s completely wrong!”. In the end, the project manager had to ask the customer to take responsibility of really explaining the needs so the developers could understand it, and the developers, in turn, has to really listen.
- The project was planned in three main iterations, and near the end a fourth was added to catch up with postponed stories. After each iteration, a demonstration was done for the customer so they could see the progress. However, when the third iteration was nearing its end, the developers on the team persuaded the project manager to skip the demonstration, because work at that point was very hectic to finish up the project. They skipped the demonstration, but as a result; the customer started asking questions: Had they made progress? The point is; that in order work without a specific requirements specification, customer and supplier has to trust each other, and the customer has to be able to track the progress.
When go agile, and when to use waterfall
Ole explained that many people like to view the options for choosing a development method as two extremes:
- A large, predictable, complex project where requirements can be specified up front: Waterfall
- A smaller, dynamic (often web-) project: Agile
In Ole’s experience, though, there are no projects that won’t benefit from agile methods one way or another, while there are projects that will just never work with a waterfall model, because requirements are changing all the time. He also pointed out that if your project might fail, it should fail as early as possible.
Architecture in agile development projects
One of the big concerns of experienced developers considering going agile, is what happens to the architecture of the system being developed. Traditionally, one or more architects have laid the groundwork in designing the entire object model before the programmers where allowed to begin their part of the work. A traditional architect would consider it an embarrassment if his design has to be changed because of flaws or unforeseen things, but agile development does not allow much time for BDUF (Big Design Up Front).
The argument against BDUF is another acronym; YAGNI (You Ain’t Gonna Need It), which stresses the point that in trying to make a design that covers any conceivable aspect of the system, you are actually wasting a lot time designing - and often also implementing - stuff that will never be used. However, Ole explained, agile methods are in no opposed to architecture, it is just that the architect design, drawings and diagrams becomes less important, while the architects themselves becomes much more important.
Some agile practitioners are of the opinion that no dedicated architects are needed at all; all programmers are architects and visa versa. The purpose is that everyone “owns” the entire code base, so everyone is capable of making changes anywhere. Ole, however, does not like the idea of everyone making architecture decisions jointly - he prefers that a chief architect makes the final decisions and is responsible for keeping the design consistent and clear.
The above is just a fraction of all the exciting stuff I’m learning about agile development at the moment, and remember: You are not agile just because you code ad-hoc without planning your stuff in a code-and-fix way. Agile development requires both discipline and experience.
Anyway, I’m off to London for the next week and I’m not bringing my laptop, since I’m afraid of something happening to my precious, yet fragile Macbook Pro - so I’ll be offline for a week…