Agile development has been a pervasive force within software development, and its influence is spreading further still. Individuals on the business side have gotten the Agile bug – they expect fast action, quick iterations, and a steady stream of deliverables. Since integration is essential to all applications, the department of the enterprise integration architect is called on to be as Agile as a development team in a scrum.
In the shadows of the Agile movement, prepped to take a more prominent position, is the ''Lean movement.'' Sometimes people use the terms ''Agile'' and ''Lean'' interchangeably. Lean principles are a bit more akin to modern manufacturing principles, made famous by carmaker Toyota. What especially marks Lean methods? It is a drive to eliminate waste.
Lean theories are coming to encompass middleware integration development as well as standalone application development. A book from 2010 that has led the way is ''Lean Integration: An Integration Factory Approach to Business Agility'' by John G. Schmidt and David Lyle.
Among the telling portions of the book is a section on integration wastes. The authors of ''Lean Integration'' build on the work of Mary and Tom Poppendieck, authors of ''Implementing Lean Software Development,'' who in turn build on the established concepts of waste that are familiar in manufacturing and production. Schmidt and Lyle extend these to encompass application integration practices.
Examples of production waste (or, ''muda'') are transportation waste related to unnecessary movement of materials; inventory waste, typically in the form of excess inventory; and motion, where extra steps are used to perform a job. These factory phenomena have analogies in development and integration.
The Poppendiecks map these concepts into the software development realm, where transportation waste might mean unnecessary data handoffs. Excess inventory here could mean development work that never actually gets deployed. Further, industrial motion waste could translate in this world view to excessive task switching by members of development teams.
Mapping Lean integration
How does all this map onto the discipline of application integration? Well, authors Schmidt and Lyle see parallels. What might be unnecessary movement of materials in the factory could be called ''gold-plating'' when it comes to integration. Building functional integration capabilities or extra features before they are needed is the culprit practice to which the authors of ''Lean Integration'' point.
Gold-plating especially unnerves business leaders, they write. They feel their project is being made to carry the burden of others. Schmidt and Lyle have a humorous metaphor to describe this. It is, ''the first person on the bus pays for the bus.''
Here, the SOA practitioner may take offense. Services require an enterprise view – poorly formed services, the SOA practitioner would assert, only lead to integration silos that require re-work later on. The authors of ''Lean Integration'' suggest integration architects should ''build only the features/functions that the first project requires, and do so in such a way that they can be extended in the future when the second project comes along.''
"... If the nature of change is such that the second project requires refactoring of the solution that was developed for the first project, so be it. This approach is more desirable because of the risks and 'muda' of building functionality prematurely.''
Yes, this is controversial. Lean integration may seem to run contrary to important SOA principles - just as Agile development has appeared at times to be in opposition to SOA, or even to enterprise architecture, for that matter. But the book provides food for thought. The authors discuss ''using middleware like peanut butter'' ( or, ''applying it everywhere''), reinventing the wheel and unnecessary complexity as other forms of wasteful integration practices.
Much of ''Lean Integration'' is a good read. It is an important book with an often interesting perspective.
More information on ''Lean Integration''
''Lean Integration: An Integration Factory Approach to Business Agility'' (Addison Wesley, 2010) John G. Schmidt and David Lyle - SafariBooksOnline