Enterprise IT needs some fundamental changes in perspective. Learning lessons from two new service-oriented approaches - APIs and microservices - we find that enterprises need to shift their perspective from applications to services and from projects to products. Presented at APIdays Sydney on February 11th 2015.

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Delivering the Composable
Enterprise
APIdays Sydney
Feb 11th 2015

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API-eye for the Enterprise Guy

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• Bezos big mandate
• Jonathan Murray
Fundamentally based around SOA but
more specifically about how you do it
The Composable Enterprise

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[Jeff Bezos’] Big Mandate went something along these lines:
1) All teams will henceforth expose their data and functionality through
service interfaces.
2) Teams must communicate with each other through these interfaces.
3) There will be no other form of interprocess communication allowed: no
direct linking, no direct reads of another team's data store, no shared-
memory model, no back-doors whatsoever. The only communication
allowed is via service interface calls over the network.
4) It doesn't matter what technology they use. HTTP, Corba, Pubsub,
custom protocols -- doesn't matter. Bezos doesn't care.
5) All service interfaces, without exception, must be designed from the
ground up to be externalizable. That is to say, the team must plan and
design to be able to expose the interface to developers in the outside
world. No exceptions.
6) Anyone who doesn't do this will be fired.
7) Thank you; have a nice day!
(Source: Steve Yegge’s (in)famous platform rant: https://plus.google.com/112678702228711889851/posts/eVeouesvaVX)
Bezos’ Big Mandate

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Our technologies are almost exclusively implemented as services:
bits of logic that encapsulate the data they operate on and provide
hardened interfaces as the only way to access their functionality. This
approach reduces side effects and allows services to evolve at their
own pace without impacting the other components of the overall
system. Service-oriented architecture -- or SOA -- is the fundamental
building abstraction for Amazon technologies. Thanks to a thoughtful
and far-sighted team of engineers and architects, this approach was
applied at Amazon long before SOA became a buzzword in the
industry. Our e-commerce platform is composed of a federation of
hundreds of software services that work in concert to deliver
functionality ranging from recommendations to order fulfillment to
inventory tracking. For example, to construct a product detail page for
a customer visiting Amazon.com, our software calls on between 200
and 300 services to present a highly personalized experience for that
customer.
Amazon.com Shareholder’s Letter 2010

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Jonathan Murray: CIO of Warner Music Group
http://www.adamalthus.com/blog/2013/04/04/the-composable-enterprise/
• The Minimal Function: work with the minimal 'atomic'
functions that your enterprise needs.
• Least Dependency: eliminate the dependencies between
functions.
• Shared Knowledge: maximize safe access to data to the
broadest audience.
• Predictable Contracts: every function defines its inputs,
authorizations, output products and performance
guarantees.
• Maximized Human Value: humans only do what can't be
automated.
The Composable Enterprise

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…fundamental shifts in perspective
Applications Services
Projects Products
We Need…

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• Business processes become tightly
coupled to applications (in two ways)
• Users constrained by application
capabilities
• Processes influenced by an application
view of the world
• Confusion about system responsibilities
• The Leap of faith
The Application Perspective

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The Leap of Faith

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The Leap of Faith

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The Leap of Faith
The leap of faith

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• Funding models
• Design blindness
• The “somebody else's problem” effect
• Project managers making architectural
decisions based on budget & scope
• Point to point interfaces
• JABOWS
• JABORS
The Project Perspective

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• Developer engagement is critical
• API/Product life cycle
• API Catalogue
• Metrics & Analytics
• Self serve governance
• API first design
• Strict separation of providers &
consumers
Lessons from APIs

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• DDD – Eric Evans
• Don’t try for a single Common Information
Model
• Recognise multiple “bounded contexts”
• Conways Law
• Hand-offs & lost visibility
• The ICC Ghetto
• Vertically integrated teams
• Agile techniques - CD, DevOps
• Lean manufacturing principles
• If it hurts…do it ‘til it doesn’t
Lessons from Microservices

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Conclusion
…fundamental shifts in perspective
Applications Services
Projects Products