The road to event-driven architecture.

1. GOTO EDA DAY 2022
© 2022, Amazon Web Services, Inc. or its affiliates.
© 2022, Amazon Web Services, Inc. or its affiliates.

2. The Road to Event-Driven
Architecture at LEGO.com
Sheen Brisals
The LEGO Group

3. Sheen Brisals
Engineer. Architect. Writer. Speaker. Leader.
AWS Serverless Hero
@ The LEGO Group
Ex: Oracle, Hewlett-Packard, Omron, TATA
sheenbrisals
sbrisals.medium.com
sheen-brisals

5. Amazon S3
CDN/WAF
AWS WAF
AWS Fargate
Amazon ElastiCache
Amazon API
Gateway
AWS Lambda
AWS Lambda
Amazon Kinesis
Data Firehose
AWS Lambda
Amazon Event
bridge
Amazon SQS
Amazon Dynamo
DB
Amazon SNS
Amazon
CloudWatch
Third party
payments
ecommerce etc
AWS Step
Functions
LEGO.com high level architecture
100% Serverless
on AWS
FE & BFF
on Fargate

6. C4 Motoring TV Program
1998 - 2002
competition-driven due to the success of Top Gear

7. In our gravity-driven world,
everything is driven by something!

8. test-driven development behaviour-driven
schema-driven / API-driven development
data-driven decision making
domain-driven design
model-driven engineering
event-driven architecture

9. test-driven development behaviour-driven
schema-driven / API-driven development
data-driven decision making
domain-driven design
model-driven engineering
event-driven architecture
failure-driven

10. The Runway To EDA
➢ Monolith & Painful Failures
➢ Future Wishlist & Bold Start
➢ EDA – Expansion & Acceleration
➢ Microservices & Set-Pieces
➢ EDA Effects

11. Monolith Days 2016

12. The then shop.LEGO.com
Pool A Pool B
Drain Shutdown Deploy Test Release

13. Journey of a bug fix
WEB-107
Raised
28 Nov 2016
Dev
16 Mar 2017
QA
24 Mar 2017
Done
27 Mar 2017
8.11
Release
24 May 2017

14. Failure Days 2017

15. Black Friday with a monolith
VPC
Node.js
+
React
Elastic Beanstalk
container
Server contents Server contents
Tax
Products CRM
Fulfillment Rewards
VPC
Gateway
503 Service
Unavailable
Corporate
data center
Server contents

16. Points of failure
VPC
Node.js
+
React
Elastic Beanstalk
container
Server contents Server contents
Tax
Products CRM
Fulfillment Rewards
VPC
Gateway
Corporate
data center
Server contents
Monolith
One big database
Fixed scaling
On-premises
Tight coupling
Unstable 3rd party
gateway
Containers
chaos
Scaling
constraints
Legacy
Limited DB
connections
Deployment
nightmare
Non cloud 3rd
party system
No end-to-end
observability

17. Future Thinking

18. Business
Expansion
Reach more children - Enter new markets
Development
Agility
Product innovation – Team velocity – MVP to MVP
Operational
Visibility
Platform observability – Proactive monitoring - DevOps
Business demands
Minimum Viable Product
Maximum Valuable Product

19. Scalability
Resiliency
Extensibility
Availability
Observability
How can the platform scale independently?
How can innovate for customers with freedom?
How can global customers use the platform 24x7?
How can we be proactive & make data-driven decisions?
How can handle peaks & troughs automatically?
Technical needs

20. Modular
Extensible
Observable
Characteristics of
Sustainable
Products
• Domains, boundaries, contracts
• Independent smaller microservices
• Asynchronous and loosely coupled
• Event-driven architecture
• Structured logs and distributed traces
• Measurable metrics
Products’ characteristics

21. Technical challenges
Complex domain
Limited and accumulated knowledgebase
Disruption to customers and business
Serverless, unheard of
Potential delays and derailments
Cloud was all new
Too many options
Build vs buy

22. Speedy adoption
Endless experimentation
start simple
iterate, evolve
follow proven patterns
solution first;
perfection next
continuous
improvement
judgmental
can’t take risk
vendor lock-in fear
invest in expansive
processes
wait for a perfect
moment
async & event-driven

23. The first step!

25. “No one starts perfect with
Serverless, but strive to be
better at every iteration, and
that is important.”

26. Do It
Do It Right
Do It Better
- Allen Helton
https://bit.ly/3wfmwLr

27. If you spend too much thinking about a thing,
you will never get it done
- Bruce Lee

28. Transform
feed
Transformed
feeds queue
Feeds
store
Headless
commerce
platform
Update
data
Data
feeds
Trigger Push Trigger Update
DLQ
First taste of event-driven computing
Legacy commerce platform RDBMS
Data
feeds
Outperformed the
legacy system!

29. EDA Phase 1
The event-driven expansion

30. It’s all about event-driven computing

31. Headless
commerce
platform
Data
feeds
Trigger
Push Trigger
Update
Push Trigger
Push Trigger
Product
Pricing
SKU
DLQs
18
Event-driven data pipelines Learned the power of
granularity in serverless

32. Kinesis
Data Firehose
API
Gateway
S3
bucket
Event
producer
Transformation
and validation
Backup
Fan-out
function
Processing
functions
Trigger
Async
Errors
Click-stream event ingestion & distribution
Appreciated the efficiency of
Kinesis family!
100s of millions events
ingested daily

33. Admin user Vouchers API Request handler Generate vouchers Voucher backup
Voucher topic
Email notification
Email with Amazon S3 signed URL
Acknowledge
POST
GET
Async
Sync
Rewards generation and notification
1000s of voucher
generation at a time
Learned the decoupling of batch
jobs and event notifications

34. Customer topic
New commerce
platform
New customer
data handler
Customer
created
Fetch
data
Update data
Reward customer
handler
Saved payment
data handler
Fetch
data
Fetch
data
Update data
Update data
On-demand customer data migration
Serverless and legacy in
harmony!
Take bold steps, think differently &
trust event-driven architecture

35. Wait… where is EventBridge?
It wasn’t there!

36. 10, July 2019
LEGO.com
was switched to
serverless

37. 11, July 2019
Amazon EventBridge
was released
Amazon EventBridge
Custom event bus
Default event bus
Partner event bus
Event producers
(sources)
Event consumers
(targets)
Partner apps
Custom apps
AWS services
Event bus Filtering &
routing rules

38. EDA Phase 2
The event-driven acceleration

39. Serverless computing enables to build event-driven
systems faster, because it speeds the feedback-cycle
so that the system iterates more efficiently.
Dave Anderson, author of ‘The Value Flywheel Effect’

40. Agile, iterative, event-driven, and automated serverless
development is like a gravity defying take-off.
Once lifted-off, there’s no stopping!

41. It’s all about event-driven architecture

42. Prove yourself that serverless works!
Convince your colleagues that serverless is fun!
Satisfy your stakeholders that serverless is good!

43. Entangled event-driven architecture
Lambda pinball architecture
Lambda pinball architectures characteristically
lose sight of important domain logic in the
tangled web of lambdas, buckets and queues as
requests bounce around increasingly complex
graphs of cloud services.
Thoughtworks

44. What’s the solution?
Microservices! Yay!!

45. Still tangled

46. Amazon EventBridge

47. Choreography vs Orchestration

48. Choreography

49. Choreography
This Photo by Unknown Author is licensed under CC BY-SA-NC
Event Bus
Publisher Subscriber
Publisher Publisher
Publisher
Subscriber
Subscriber Subscriber
• No conductor
• Pub-sub model
• Service decoupling
• Asynchronous
• Idempotency
• Traceability
Use choreography to coordinate
different microservices

50. Orchestration

51. Orchestration
• Orchestrator
• Workflow
• Long running
• Coordination of tasks
• Low code
• Pause & resume
Data
Process
Process Process
Use orchestration inside
microservices
Use distributed orchestration
across microservices

53. Microservices
Thinking in set-pieces

54. Domain-Driven Design
It’s not a book. It’s an industry!

55. Domain-Driven Design
Published in 2003
Influenced by OO principles
Filled with UML models
Projects focussed

56. Domain-Driven Design
Domain model
Supple design
Bounded context
Anticorruption layer
Distillation of core domain
A system that is hard to understand is hard to change

57. If domain thinking is like
seeing the forest…
Set-piece thinking is like
looking at the trees

58. Visualise the whole but focus in parts.
I just don’t think it’s that simple. Nothing is.
Everything is, when you break it down!
Mama Mia! Here We Go Again
See the forest before looking at the trees.

59. Vision and Focus

65. What is a set-piece?

66. A scene or sequence of scenes
whose execution requires
logistical planning
A realistic piece of stage scenery
built to stand independently as
part of a stage set

67. A rehearsed team manoeuvre
practised in training in
advance of matches
Parts of a model that are
built separately and
assembled together

68. Developing as Set-Pieces requires planning and
execution, but can be developed and tested
independently, and brought together.

69. Payments
• One monolith single service
• One delivery pipeline
• One unified complex view
(Sub) Domain view

70. Payments
commit build test stage production
One delivery pipeline

71. Payments
Higher degree of change
Authorization
Logic
If a part changes frequently, how can
we isolate the disruption?
How can we prevent deploying
everything every time?
(Sub) Domain view

72. Payments
Set-Piece view
Authorizaton Pay by Link
Refunds Settlements
Fraud
engine
Reports
Notifications
(Sub) Domain view

73. commit build test stage production
Refunds
Reports
Authorization
commit build test stage production
commit build test stage production
Independent delivery pipelines

74. How do set-pieces work together?

75. Music
Background
score
Interfaces
Ball,
Referee
Dialogue
Set-Piece
Glue

76. Events
Messages
Set-Piece
Connectors
Clients
Refunds Reports
Fraud
checks
APIs
Choreography
Orchestration

77. • Mostly synchronous
• Request-response
• Coupled services
• Quick response
• Asynchronous
• Push-pull pattern
• Decoupled services
• Message buffer
• Asynchronous
• Pub-sub pattern
• Decoupled services
• Multiple targets
APIs Events
Messages
API
API Push
Pull
Queue
Pub
Sub
Event bus

78. Set-Piece Case Study
The Loyalty Service

79. LEGO Loyalty Program
Till
Loyalty
customer
LEGO store
Loyalty
service
Order placed
Rewards
selected
LEGO.com
External
applications
Services
Existing
VIP
New
VIP

80. Public client
Loyalty Service Platform
SaaS
CRM
SaaS
Survey
LEGO
Data Lake
Domain
Subdomain
Bounded context
Ubiquitous language

81. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake

82. Subdomain
Bounded context
Domain
Ubiquitous language
API landing zone
Identifying the pieces

83. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator

84. 3rd party isolation
Subdomain
Bounded context
Domain
Ubiquitous language
API landing zone
Identifying the pieces

85. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus

86. 3rd party isolation
Subdomain
Bounded context
Domain
Ubiquitous language
API landing zone
Common resources
Identifying the pieces

87. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin

88. 3rd party isolation
Subdomain
Bounded context
Domain
Ubiquitous language
API landing zone
Common resources
Support services
Identifying the pieces

89. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor

90. 3rd party isolation
Subdomain
Bounded context
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Support services
Identifying the pieces

91. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor
Audit
Service

92. 3rd party isolation
Subdomain
Bounded context
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Event source audit
Support services
Identifying the pieces

93. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor
Audit
Service
Fraud
Engine

94. 3rd party isolation
Subdomain
Bounded context
Service intelligence
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Event source audit
Support services
Identifying the pieces

95. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor
Audit
Service
Fraud
Engine
Rewards
Manager

96. Service intelligence
Management tasks
Identifying the pieces
3rd party isolation
Subdomain
Bounded context
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Event source audit
Support services

97. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor
Audit
Service
Fraud
Engine
Rewards
Manager
Webhook

98. Service intelligence
Management tasks
Notifications
Identifying the pieces
3rd party isolation
Subdomain
Bounded context
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Event source audit
Support services

99. Public client
Loyalty Service Platform
SaaS
CRM
Loyalty
Core
SaaS
Survey
LEGO
Data Lake
Data
Feeder
NPS
Provider
CRM
Mediator
Event
Bus
Auth
Service
Loyalty
Admin
Order
Processor
Audit
Service
Fraud
Engine
Rewards
Manager
Customer
Search
Webhook

100. Service intelligence
Management tasks
New features
Notifications
Identifying the pieces
3rd party isolation
Subdomain
Bounded context
Async activities
Domain
Ubiquitous language
API landing zone
Common resources
Event source audit
Support services

101. 3rd party isolation
Subdomain
Bounded context
Service intelligence
Async activities
Domain
Ubiquitous language
API landing zone
Common resources Management tasks
Event source audit
New features
Support services Notifications
?
Identifying the pieces

102. Public client
Loyalty Service Platform
SaaS
CRM
Data
Feeder
Loyalty
Core
Event
Bus
Audit
Service
Order
Processor
Auth
Service
Loyalty
Admin
Rewards
Manager
Customer
Search
SaaS
Survey
LEGO
Data Lake
NPS
Provider
CRM
Mediator
Fraud
Engine
Webhook

103. Handling a loyalty order

104. API client /orders
Session data
Audit
Orders
order request
order response
order received
order request
order response
order received
order processed
order error
Loyalty core
Audit
Order processor

105. SaaS
CRM
API client /orders
Session data
Audit
Orders
order request
order response
order received
order request
order response
SaaS
Survey
NPS log
order processed
order received
order processed
order error
Loyalty core
Audit
Order processor
NPS provider
CRM mediator

106. How do you find the events?

108. EventBridge Storming

109. Loyalty Service Platform
Loyalty
Core
Event
Bus
Audit
Service
Order
Processor
Auth
Service
Loyalty
Admin
Rewards
Manager
Customer
Search
NPS
Provider
CRM
Mediator
Fraud
Engine
Webhook
Domain events
• Business significant
• Outward & inward flowing
• Restricted access
Operational events
• Internal visibility
• Messengers & Catalysts
• Available to all pieces
Data
Feeder
Gatekeeper service bus
Internal
Event
Bus
Gate
Keeper
Bus
External
subscribers

110. What’s in an event?

111. Anatomy of an EventBridge event
{
}
AWS Section
User Section
JSON document
{
"version": "0",
"id": "6a7e8feb-b491-4cf7",
"detail-type": "order-submit",
"source": “service-checkout",
"account": "123456789012",
"time": "2019-08-29T12:10:21Z",
"region": "eu-central-1",
"resources": ["arn:…checkout-bus"],
"detail": {
}
}

112. {
}
AWS Section
User Section
JSON document
{
"version": "0",
"id": "6a7e8feb-b491-4cf7",
"detail-type": “order-submit",
"source": “service-checkout",
"account": "123456789012",
"time": "2019-08-29T12:10:21Z",
"region": "eu-central-1",
"resources": ["arn:…checkout-bus"],
"detail": {
}
}
“any valid JSON goes here… but,
a structure is recommended”
everyone anything
nothing

113. {
}
AWS Section
User Section
JSON document
{
"version": "0",
"id": "6a7e8feb-b491-4cf7",
"detail-type": “order-submit",
"source": “service-checkout",
"account": "123456789012",
"time": "2019-08-29T12:10:21Z",
"region": "eu-central-1",
"resources": ["arn:…checkout-bus"],
"detail": {
"metadata": {
},
"data": {
}
}
}
standard structure

114. {
}
AWS Section
User Section
JSON document
{
"version": "0",
"id": "6a7e8feb-b491-4cf7",
"detail-type": “order-submit",
"source": “service-checkout",
"account": "123456789012",
"time": "2019-08-29T12:10:21Z",
"region": "eu-central-1",
"resources": ["arn:…checkout-bus"],
"detail": {
"metadata": {
“domain”: {
“name": “LEGO-SHOP",
“service": “service_checkout",
"type": "ORDER",
"status": “SUBMITTED“ // SUCCESS, ERROR, RETRY
},
“traceId”: “hdfhdf-74jdf-sy63s”,
“TTL”: “1689576169”,
“activity”: “INFO” // COMMAND, DATA, REQUEST
},
"data": {
"orderNumber": "T123456789",
"customerId": "bf3703467718“,
“locale”: “en-GB”,
“value”: 59.99
}
}
}

115. The Experience
Effect of EDA adoption

116. You cannot create experience,
you must undergo it
- Albert Camus

117. Team growth

118. Spring 2018
Ecommerce team
From…
• 1 team
• 10 engineers
• 1 monolith
• 8 application servers

119. July 2019
Serverless team Front-end team
• 2 squads
• 20 engineers
• 2 repositories
• 1 AWS prod account
• 20 microservices
• 100 lambda functions

120. Summer 2022
payments
loyalty platform
content
insights
POS
products checkout
orders campaigns consumers
• 25+ squads
• 150+ engineers
• multiple repositories
• multiple AWS prod accounts
• many microservices
• many lambda function
• and growing!
basket
OMS store APP
CSC consent accounts
rewards
bricks

121. Business growth

122. Record breaking
sales weekend
August 2020
November 2020
Record breaking
BFCM weekend
November 2019
Record breaking
BFCM weekend
Record sales BFCM
weekend
Part Serverless
November 2018

123. Spikes do no harm
200x
Transactions
processed
9.5x
User traffic

124. The future is already here;
it’s just not very evenly distributed.
- William Gibson
To close…

125. The future is already here;
it’s just not very evently distributed.
Let event-driven architecture be the enabler!

126. https://bit.ly/3iOXHhY

127. Go
Build
Serverless
Thank
You!
sheenbrisals
sbrisals.medium.com
sheen-brisals

128. GOTO EDA DAY 2022
© 2022, Amazon Web Services, Inc. or its affiliates. 128
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