"Composability is a system design principle that deals with the inter-relationships of components. A highly composable system provides recombinant components that can be selected and assembled in various combinations to satisfy specific user requirements. The essential features that make a component composable are that it be: a) self-contained (modular): it can be deployed independently - note that it may cooperate with other components, but dependent components are replaceable..." (Wikipedia)
"Composability (http://en.wikipedia.org/wiki/Composability). That is, businesses must start to reimagine themselves as sort of active Lego blocks, which can be clicked together in almost any way by almost anyone to create almost any form desired.
Lego bricks are a good metaphor because they are so friendly; everyone knows them, everyone knows what they are. Snap a few bricks together and you already know almost everything about composability you’ll ever need to learn. They work because every bring presents a standardized, regular surface to every other brick.
What’s true for bricks is now becoming true for all services. Every function of a bank (see Sean Park’s slide) is now being disrupted by an organization that offers an interface for just that one little bit, in a standardized fashion, so that anyone can take that interface and bulid their own piece - their own brick - on top of it. Financial services are, through the competitive force of the disrputively lower cost structure of these new business models, being disrupted, and every bank is being crowded onto the API bus.
This means it is essential for every business (and bank and every financial institution) to think of itself as a composable and decomposable entity. How does your aggregation of services add value? Does it add value, or is it simply hindering your customer’s ability to create their own value chains from your services?" (SIBOS contribution)