EA for intentional business transformation
APIs with a
PURPOSE
Roger Stoffers
Presenting as
independent speaker
Roger Stoffers, Enterprise Architect, Author
Presenting here as independent architect
Personal
54y, married, 2 children
The Netherlands, Europe
Passions:
Reading / Authoring
Karting / Horseback riding
Professional
30+ years in the field
Developer
Various architecture roles
Principal Integration Architect
Enterprise Architect
Passions:
Digital Transformation
Business Transformation
(Business) Integration
Current:
EA at ASN Bank
Owner of Suresult
Author, Consultant, Coach
Advising roles
present
past
Introducing Regent & Rye
Integration as tech plumbing. Capabilities lacking flow. Fictional
160 yo luxury
bakery
Vision
Mission
Strategy
Launch partner
marketplace
Lift B2B
Loyalty
Reduce
cost-to-change
Architectural
debt
Strategy blockers
Organisational
structure
Capability Map
Loyalty
Offers
Ordering
Partner Onboarding
Settlement
Capabilities
trapped in
systems
across teams
Fulfilment
Future innovation:
Explore AI
-/- -/-
Capability Map
Enterprise Architecture at work
Value can’t flow without purposeful integration
Loyalty
Ordering
Partner Onboarding
Settlement
Fulfilment
Offers
Architectural
debt
Strategy blockers
Organisational
structure
Rules & Data
spread across
20 systems
20 systems
managed by
5 teams
A single API
calls 3-5 others
A single change
involves
3-4 teams
Symptoms
Change lead time
6-12 weeks
Team myOrdering Team NewDeli
Enterprise Architecture at work
Loyalty
Offers
Ordering
Partner Onboarding
Settlement
Fulfilment
LegacyOrdering
2ndGenOrdering
Catalog
NewCatalog
RRDelivery
NextGenDelivery
Team “Stork”
Fulfilment
RRDelivery
NextGenDelivery
Team “Kingfisher”
Offers
Catalog
NewCatalog
Establish a “composable organization”… but how … ?
… an organisation geared for sustainable effective and efficient change …
Business Capability: Delivery
Business Capability: Ordering
Business Capability Operating Models
A mechanism for finding candidate APIs: Business Integration at heart!
Ordering
Delivery
Roles
Automation
Data
Process
Data Roles
Automation
Process
/Order
/Deliver
/Return
Order Capture
Organisational module /
Reusable business component (*)
(*) J. Ross
Pick order
Ship order Allocate Loyalty Pts
Business Process Integration
{API}
Business Process
Order Delivery
APIs as Productised Promises
• Name + Definition
• Purpose
• Business Data
• Terms of Use
• SLA
• Policy Model
• Version(s)
• Consumers
• Providers
Business
Owner
Accountable…
Sponsor…
/Ordering

Value team
Responsible for “change”
API Canvas
“Business Contract”
API Qualities(*)
Standardised
Interoperable
Loose coupling
Reusable
Discoverable
Autonomous
(*) Thomas Erl: Principles of Service Design
Now that
is an API!

Balance qualities wisely!
Find APIs:
only
then…
Execution
Build the product, not a project…
Business Analysis
Business
Process
domains
Data
domains
Roles & Responsibilities
Organise teams around this
Allocate applications
/Ship
/Offer
/Payment
Product
delivery
sliced into
compound
value
Besides APIs, mind business events!
- new capabilities, real-time analytics & decisioning
- one-to-many async deeply decoupled integrations
- extra layer of scalability and flexibility and central to composability
Outcomes
Metrics the board funds: from uptime to business outcomes…
Marketplace live in 8 weeks
Partner onboarding from
6 weeks to 5 days
Cost to change: -30%
Loyalty redemption rate: +22%
API reuse ratio:
3.8x across journeys
Innovation: Explore AI-assisted enterprise
Drive loyalty:
Programmable Coupons
with predictable outcomes
Sales
Catalog mgt.
Budget mgt.
Coupon mgt.
Business Analysis
Business
Process
domains
Data
domains
Roles & Responsibilities
Organise teams
Build Loyalty Agent
Agent roles:
- Analyser, Planner
- Monitor & Controller, Veto-er
Eagle team (sales)
Hawk team (controller)
Drive loyalty:
Programmable Coupons
with predictable outcomes
Sales
Catalog mgt.
Budget mgt.
Coupon mgt.
Agent roles:
- Analyser, Planner
- Monitor & Controller, Veto-er
Eagle team (sales)
Hawk team (controller)
UX /
Channels
Customer
Engagement
SoR
Fallout mgt
Monitoring & Control
Ordering
Rules
 / 
/Product
/Compatibility
/Budget
/Eligibility
/Coupon
/Offer
/PartnerIdentity /Orderhistory /Pricing /…
APIs make loyalty composable; agentic AI makes them self-improving
while deterministic guardrails make outcomes dependable by limiting agent creativity.
Guard rails: 6 strategies
1. A specific agent for each distinct purpose
- Analyser, Planner, Veto-er
2. Only access to relevant APIs (deterministic)
- Access: Pricing, Coupons, Products,
Customers, Orders
- No access: Employee, Payroll,
Accounts, …
3. High-quality APIs
- Standardised, interoperable,
documented, distinct, semantically
clear
4. Business Rules (deterministic)
- Customer only sees valid offers
5. Orchestrated processes where needed
(deterministic)
- Monitoring/control, fallout
6. Human in the loop: Hawk team
- Monitoring & control
- Veto
Business Analysis + KPIs
= relevant innovation loop
Takeaways
APIs are
strategic
interfaces into
business
capabilities
Business
Capabilities:
operating
model ensuring
it behaves as a
reusable
business
component
Interfaces are
standardised,
interoperable,
decoupled,
defined for
business
Measure
what matters
to business:
outcome over
uptime
Avoid
the tech trap:
an HTTP
endpoint is not
an API
Analyse
process first,
only then the
rest!
(organization,
automation, …)
Policy in code
≠
strategy in
motion
Enabler for Agentic AI

AI


AI


AI


AI


AI


AI

Many of the principles for API design
are needed for the enabling of Agentic AI (through RAG)
Questions
?? ??
End
Author
Training & Consulting
Coaching & Empowering
Roger Stoffers, resultant

apidays Amsterdam 2025 | APIs with a Purpose

  • 1.
    EA for intentionalbusiness transformation APIs with a PURPOSE Roger Stoffers Presenting as independent speaker
  • 2.
    Roger Stoffers, EnterpriseArchitect, Author Presenting here as independent architect Personal 54y, married, 2 children The Netherlands, Europe Passions: Reading / Authoring Karting / Horseback riding Professional 30+ years in the field Developer Various architecture roles Principal Integration Architect Enterprise Architect Passions: Digital Transformation Business Transformation (Business) Integration Current: EA at ASN Bank Owner of Suresult Author, Consultant, Coach Advising roles present past
  • 3.
    Introducing Regent &Rye Integration as tech plumbing. Capabilities lacking flow. Fictional 160 yo luxury bakery Vision Mission Strategy Launch partner marketplace Lift B2B Loyalty Reduce cost-to-change Architectural debt Strategy blockers Organisational structure Capability Map Loyalty Offers Ordering Partner Onboarding Settlement Capabilities trapped in systems across teams Fulfilment Future innovation: Explore AI -/- -/-
  • 4.
    Capability Map Enterprise Architectureat work Value can’t flow without purposeful integration Loyalty Ordering Partner Onboarding Settlement Fulfilment Offers Architectural debt Strategy blockers Organisational structure Rules & Data spread across 20 systems 20 systems managed by 5 teams A single API calls 3-5 others A single change involves 3-4 teams Symptoms Change lead time 6-12 weeks
  • 5.
    Team myOrdering TeamNewDeli Enterprise Architecture at work Loyalty Offers Ordering Partner Onboarding Settlement Fulfilment LegacyOrdering 2ndGenOrdering Catalog NewCatalog RRDelivery NextGenDelivery Team “Stork” Fulfilment RRDelivery NextGenDelivery Team “Kingfisher” Offers Catalog NewCatalog Establish a “composable organization”… but how … ? … an organisation geared for sustainable effective and efficient change …
  • 6.
    Business Capability: Delivery BusinessCapability: Ordering Business Capability Operating Models A mechanism for finding candidate APIs: Business Integration at heart! Ordering Delivery Roles Automation Data Process Data Roles Automation Process /Order /Deliver /Return Order Capture Organisational module / Reusable business component (*) (*) J. Ross Pick order Ship order Allocate Loyalty Pts Business Process Integration {API} Business Process Order Delivery
  • 7.
    APIs as ProductisedPromises • Name + Definition • Purpose • Business Data • Terms of Use • SLA • Policy Model • Version(s) • Consumers • Providers Business Owner Accountable… Sponsor… /Ordering  Value team Responsible for “change” API Canvas “Business Contract” API Qualities(*) Standardised Interoperable Loose coupling Reusable Discoverable Autonomous (*) Thomas Erl: Principles of Service Design Now that is an API!  Balance qualities wisely!
  • 8.
    Find APIs: only then… Execution Build theproduct, not a project… Business Analysis Business Process domains Data domains Roles & Responsibilities Organise teams around this Allocate applications /Ship /Offer /Payment Product delivery sliced into compound value Besides APIs, mind business events! - new capabilities, real-time analytics & decisioning - one-to-many async deeply decoupled integrations - extra layer of scalability and flexibility and central to composability
  • 9.
    Outcomes Metrics the boardfunds: from uptime to business outcomes… Marketplace live in 8 weeks Partner onboarding from 6 weeks to 5 days Cost to change: -30% Loyalty redemption rate: +22% API reuse ratio: 3.8x across journeys
  • 10.
    Innovation: Explore AI-assistedenterprise Drive loyalty: Programmable Coupons with predictable outcomes Sales Catalog mgt. Budget mgt. Coupon mgt. Business Analysis Business Process domains Data domains Roles & Responsibilities Organise teams Build Loyalty Agent Agent roles: - Analyser, Planner - Monitor & Controller, Veto-er Eagle team (sales) Hawk team (controller) Drive loyalty: Programmable Coupons with predictable outcomes Sales Catalog mgt. Budget mgt. Coupon mgt. Agent roles: - Analyser, Planner - Monitor & Controller, Veto-er Eagle team (sales) Hawk team (controller) UX / Channels Customer Engagement SoR Fallout mgt Monitoring & Control Ordering Rules  /  /Product /Compatibility /Budget /Eligibility /Coupon /Offer /PartnerIdentity /Orderhistory /Pricing /… APIs make loyalty composable; agentic AI makes them self-improving while deterministic guardrails make outcomes dependable by limiting agent creativity. Guard rails: 6 strategies 1. A specific agent for each distinct purpose - Analyser, Planner, Veto-er 2. Only access to relevant APIs (deterministic) - Access: Pricing, Coupons, Products, Customers, Orders - No access: Employee, Payroll, Accounts, … 3. High-quality APIs - Standardised, interoperable, documented, distinct, semantically clear 4. Business Rules (deterministic) - Customer only sees valid offers 5. Orchestrated processes where needed (deterministic) - Monitoring/control, fallout 6. Human in the loop: Hawk team - Monitoring & control - Veto
  • 11.
    Business Analysis +KPIs = relevant innovation loop Takeaways APIs are strategic interfaces into business capabilities Business Capabilities: operating model ensuring it behaves as a reusable business component Interfaces are standardised, interoperable, decoupled, defined for business Measure what matters to business: outcome over uptime Avoid the tech trap: an HTTP endpoint is not an API Analyse process first, only then the rest! (organization, automation, …) Policy in code ≠ strategy in motion Enabler for Agentic AI  AI   AI   AI   AI   AI   AI  Many of the principles for API design are needed for the enabling of Agentic AI (through RAG)
  • 12.
  • 13.
  • 14.
  • 15.
    Training & Consulting Coaching& Empowering Roger Stoffers, resultant