Agile Processes – So What’s the Architecture?

About seven years ago I attended a Best Practices conference for Software Development. The seminars were on RUP (Rational Unified Process ) and CMMI (Capabilities Maturity Model ). At that time, I was working with my own company’s internal product release processes that were waterfall http://en.wikipedia.org/wiki/Waterfall_model in nature. There were a handful of seminars on agile development.

Fast forward two years: I’m attending the same Best Practices conference। And the seminars couldn’t be more different. Agile development was the subject of the vast majority of topics presented with titles like: Agile Development and XXX (you fill in the XXX). There were lively roundtables with book authors on agile. One poor fellow asked skeptical questions about agile methods and was roasted by the roundtable leaders.

And one seminar that stood out but itself because Agile was not in the title: Documenting Software Architectures with one of the authors of the same titled book। This seminar was packed and one of the most well attended of the conference.

But don’t software architecture methods and agile methods directly conflict with each other? Don’t they have different values?

Being a software architect and systems engineer at my current company, I have observed and been part of BDUF (Big Design Up Front) and features that are YAGNI (You Ain’t Gonna Need It)। I’m guessing that poor fellow that was roasted in the roundtable was also part of this effort. And yet those efforts sometimes have some incredible forethought. The foundation was laid down to allow for robust change in the future. As someone who has worked with existing architectures, I have great respect for the foresight the earlier designers had when that serendipity occurs “Wow, this is already in place and all we have to do is….”.

During a business trip with the SDM at MIT, we were visiting a software company in Dublin, Ireland that was an early user of agile methods in 2001. One of the students asked the lead software engineer how they will deal with legacy issues given the way they were using agile. The lead designer didn’t know and thought it would be a problem in the future.
Fast forward and it’s 2010। My company has rolled out agile methods and we’ve all been using them for several years now. We show improvements in productivity and reliability. And what has happened to architecture? It’s more important than ever.

Like most companies, our software systems are large and complex। An overall framework is needed at the beginning of a project and decisions that are the hardest to change during the lifecycle of the project are made.

Many architectural decisions are made during the project and the key for the architect is to communicate those changes to all stakeholders. See my previous blog on communication tools for architectural decisions.

At that conference, Agile zealots accused architects of being software dinosaurs and architects accused Agile zealots of being cowboys। I don’t really see the contradiction in the two. I’ve come from using CMMI to using Agile. Both are disciplined processes and Agile is more disciplined and constrained with the focus on the final product. Complex systems have architecture whether it is done iteravely or not. It just smart to make some of the overarching decisions before coding begins. The architect’s role continues as someone who manages key decisions and tests the code to make sure it is executing those decisions.

When those decisions are not made up front, it can be disastrous for the project (at least some that I’ve been involved in)।

I wonder there are any software developers that don’t use Agile method? Maybe not. And I also wonder if there is another better process in our future. Regardless, classes like Documenting Software Architectures will always be interesting because we all need to know “What’s the architecture?” Architecture occurs whether you have someone working on it or not. It’s better to be aware up front what it is and how it meets the business requirements of the project.