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No Man’s Land

April 28, 2011 4 comments

Having recently just read my umpteenth Watts Humphrey book on his PSP/TSP (Personal Software Process/Team Software Process) methodology, I find myself struggling, yet again, to reconcile his right wing thinking with the left wing “Agile” software methodologies that have sprouted up over the last 10 years as a backlash against waterfall-like methodologies. This diagram models the situational tension in my hollow head:

It’s not hard to deduce that prescriptive, plan-centric processes are favored by managers (at least those who understand the business of software) and demonstrative, code-centric processes are favored by developers. Duh!

Advocates of both the right and the left have documented ample evidence that their approach is successful, but neither side (unsurprisingly) willingly publicizes their failures much. When the subject of failure is surfaced, both sides always attribute messes to bad “implementations” – which of course is true. IMHO, given a crack team of developers, project managers, testers, and financial sponsors, ANY disciplined methodology can be successful – those on the left, those on the right, or those toiling in NO MAN’s LAND.

l’ve been the anointed software “lead” on two, < 10 person, software teams in the past. Both as a lead and an induhvidual contributor, the approach I’ve always intuitively taken toward software development can be classified as falling into “no man’s land“. It’s basically an informal, but well-known, Brooksian, architecture-centric, strategy that I’d characterize as slightly right-leaning:

As far as I know, there’s no funky, consensus-backed, label like “semi-agile” or “lean planning” to capture the essence of architecture-centric development. There certainly aren’t any “certification” training courses or famous promoters of the approach. This book, which I discovered and read after I’d been designing/developing in this mundane way for years, sort of covers the process that I repeatedly use.

In my tortured mind (and you definitely don’t want to go there!), architecture-centricity simply means “centered on high level blueprints“. Early on, before the horses are let out of the barn and massive, fragmented, project effort starts churning under continuous pressure from management for “status“, a frantic iterative/sketching/bounding/synthesis activity takes place. With a visible “rev X” architecture in hand (one that enumerates the structural elements, their connectivity, and the macro behavior that the system must manifest) for guidance, people can then be assigned to the sparsely defined, but bounded, system elements so that they can create reasonable “Rev 0” estimates and plans. The keys are that only one or two or three people record the lay of the land. Subsequently, the element assignees produce their own “Rev 0” estimates – prior to igniting the frenetic project activity that is sure to follow.

In a nutshell, what I just described is the front-end of the architecture-centric approach as I practice it; either overtly or covertly. The subsequent construction activities that take place after a reasonably solid, lightweight, “rev X”, architecture (or equivalent design artifact for smaller scale projects) has been recorded and disseminated are just details. Of course, I’m just joking in that last sentence, but unless the macro front end is secured and repeatedly used as the “go to bible” shortly after T==start, all is lost – regardless of the micro-detailed practices (TDD, automated unit tests, continuous integration, continuous delivery, yada yada yada) that will follow. But hey, the content of this post is just Bulldozer00’s uncredentialed and non-expert opinion, so don’t believe a word of it.