The document summarizes AutoScout24's transition from a monolithic architecture to microservices in the cloud. Some key points: - They moved from an on-premise Microsoft-based stack to AWS and a microservices architecture using JVM and Linux. - This was a major technical transformation to become "mobile first" and reduce costs and time to market while attracting new talent. - They established architectural principles like event sourcing, autonomous teams, infrastructure as code, and shared-nothing. - DynamoDB is now used as the "atom feed" between services while eliminating tight coupling. - Teams are organized around business capabilities rather than projects to improve agility.

1. Highway to heaven
Building microservices in the cloud
Munich microservices meetup, June 2015

2. Agenda
Meet AutoScout24
Shifting gears
How we build our services
How we organize ourselves

3. AutoScout24 - 10.000ft
C

4. Baseline AutoScout24 IT
Highly optimized, but of last decade
IT platform supported growth for >6 years
Microsoft oriented stack
Enterprise IT setup - MTBF over MTTR
Proven agile and lean principles
C

5. From monolith to microservices...
...via swimlanes
C

6. New CEO
C

7. Do you attract talent?
C

8. C

9. Project Tatsu
W

10. Microservices
AWS
JVM / Linux
DevOps culture
Product
Five challenges
W

11. Shiny new cut
Cut to the core
Add new business value
New user experience
W

12. Objectives
Mobile first, user centric
Sophisticated user experience
Reduce time to market
Attract talents
Reduce costs in IT production
W

13. Technical transformation
W

14. Change the wheels while driving
W

15. Strategic Goals
Goals of the business side
Architectural Principles
High-Level Principles
Design and Delivery Principles
Tactical measures
Reduce Time to Market
Speed, Fast Feedback
Cost Transparency
Collect metrics to allow decisions cost vs. value.
Support Data-Driven Decisions
Listen to users and validate hypothesis.
Provide as many relevant metrics & data as possible.
You build it, you run it
Responsibility to run and maintain a product stays with the
building team. Fast feedback from live and customers helps us to
continuously improve.
Organized around Business Capabilities
Build teams around products not projects. Follow the domain and
respect bounded contexts. Inverse Conway Maneuver
Shared Nothing
Avoid shared infrastructure and tight coupling as much as
possible. Don’t create the next monolith.
Macro and Micro Architecture
Clear separation. Autonomous micro services within the rules
and constraints of the macro architecture.
AWS First
Favor AWS service over managed service, over self-hosted OSS,
over self-rolled solutions.
Data-Driven/ Metric-Driven
Collect metrics from processes and applications. Analyze, alert
and act on them.
Eliminate Accidental Complexity
Strive to keep it simple. Focus on essential complexity. No silver
bullet.
Event Sourcing and Publishing
Keep history of state changes and publish application events.
Autonomous Teams
Make fast local decisions. Be responsible. Know your
boundaries. Share findings.
Continuous Delivery
Deliver changes reliable, often and fast.
Infrastructure As Code
Automate everything: Reproducible, traceable and tested.
Immutable servers over snowflake servers.
DevOps Culture
Developers and Ops work together in collaborative teams as
engineers. No silos.
Be Bold
Go into production early. Value monitoring over tests. Recover
and learn. Optimize for MTTR not MTBF.
Security & Data Privacy
Security must be first class citizen and everybody’s concern.
Keep data-privacy in mind.
C

16. Principles
Organized around business capabilities
You build it, you run it
Be bold
Macro and micro architecture
Event sourcing and publishing
C

17. Event Sourcing and data pumps
One way data highway
Event Sourcing - store history of all changes
C

18. SQS + S3
Kinesis + S3
Kinesis + DynamoDB
SQS + DynamoDB
Proxy + DynamoDB
DynamoDB
Evolution
W

19. Classified Events - Overview
C

20. Classified Events - Boundaries
C

21. DynamoDB as the new Atom Feed
Learn to be come a cloud native
DynamoDB as service contract
The return of the integration database?
The price is right?
W

22. DynamoDB as the new Atom Feed
Learn to be come a cloud native
DynamoDB as service contract
The return of the integration database?
The price is right?
Event Sourcing rocks
C

23. Watchlist evolution
DynamoDB as JSON document store
Scheduled user journey test
Capacity exceeded
Requests throttled
Latency spikes for real users
C

24. From documents to events
Refactoring toward deeper insight
From CRUD to sync
Offline first
Writes are expensive
USD 20 over USD 500
C

25. How many layers to estimate a price
Evolving architecture
R backend and Play application
Single Play application
Play backend and Play web server
Long feedback cycles
Frequency of change
W

26. Shared infrastructure
Shared nothing
Availability over shared nothing
Convenience offerings
No side effects
Fast local decisions over committees
W

27. Shared nothing?
How many environments?
Use over re-use
Re-use only after hardening
How to share
Copy n’paste, OSS, library
W

28. Unified log processing
AWS EC2AWS Kinesis
Event Streams
Unstructured Log
Stream
Service A
Service B
System Log
ELB Log Stream
ELB Access
Logs S3 Collector
Collector
Collector
ElasticSearch
Kibana
JSON
JSON
JSON
Collector
in progress
System Metrics Stream
Collectd
???
AWS
CloudWatch
C

29. Unified log processing
C
Optimised for imaginary use cases?
JVM metrics ... err not used
Application events over log files
What are the options?

30. How to build autonomous teams
Do not fall back into old behaviours
Beware of Mandelbrot teams
Pager duty so that you run it
Part-time ops not working
Not all T-shapes are the same
WolfCW

31. Infrastructure guild
Agree on things to do
Share learnings
Delegate implementation to teams
Empty backlog should be normal
How about infrastructure product teams?
Mind the Shirky Principle
C

32. Team over infrastructure guild
C

33. Focus sliders
Product over platform
platform
product
time
W

34. Focus sliders (cont.)
Cash stack meets shiny new stack
One company
Lights on in cash stack
Feature freeze
Where to build new features?
Ease of integration helps business people
C

35. cdeger@autoscout24.com @cdeger
wschlegel@thoughtworks.com @wolfwolf

36. Attributions
Blue sky, white-gray clouds by nature protector Natubico, www.vivism.info [CC BY-SA 3.0]
http://commons.wikimedia.org/wiki/File%3ABlue_sky%2C_white-gray_clouds.JPG
A Danish Perspective by NASA [Public domain] http://commons.wikimedia.org/wiki/File%3AA_Danish_Perspective.jpg
http://commons.wikimedia.org/wiki/File%3ANASAComputerRoom7090.NARA.jpg
GREG
EINRAD
Amazon16 by Neil Palmer/CIAT [CC BY-SA 2.0] https://www.flickr.com/photos/ciat/5641594952
BERGSTEIGER
Barber in Cameroon by James Emery from Douglasville, United States (Daddy Joe_1355) [CC BY 2.0]
http://commons.wikimedia.org/wiki/File%3ABarber_in_Cameroon.jpg
Wide objectives by Kivela (Own work) [Public domain]
href="http://commons.wikimedia.org/wiki/File%3AWide_objectives.jpg
Transformer Fire Barrier by GerryS1 (Own work) [CC BY-SA 3.0 or GFDL]
http://commons.wikimedia.org/wiki/File%3ATransformer_Fire_Barrier.jpg

37. Attributions (cont)
Alonso Renault Pitstop Chinese GP 2008 by Bert van Dijk (Pitstop F1 ING Renault) [CC BY-SA 2.0]
http://commons.wikimedia.org/wiki/File%3AAlonso_Renault_Pitstop_Chinese_GP_2008.jpg
Principle of Panchasheel by Prakash Adhikary (Own work) [CC BY 3.0]
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Traffic Jam by Doo Ho Kim [CC BY-SA 2.0] https://www.flickr.com/photos/titicat/3049591547
Pellets by The original uploader was Richard Mayer at German Wikipedia [GFDL or CC-BY-SA-3.0]
http://commons.wikimedia.org/wiki/File%3APellets.jpg
Pipes and Valves by Uwe Hermann [CC BY-SA 2.0] https://www.flickr.com/photos/73628542@N00/6272975359
Size variation in Coccinella undecimpunctata (2127991716) by Gilles San Martin from Namur, Belgium [CC BY-SA 2.0]
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Mille crêpe by Laitr Keiows (Own work) [CC BY-SA 3.0 or GFDL]
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Country Energy power line replacement 01 by Bidgee (Own work) [CC BY-SA 3.0]
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38. Attributions (cont)
Sharing Sucks (4536747557) by eyeliam from Portland, United States [CC BY 2.0]
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7Line 9184 (8263568241) by Metropolitan Transportation Authority of the State of New York (7Line_9184 Uploaded by
tm) [CC BY 2.0] http://commons.wikimedia.org/wiki/File%3A7Line_9184_(8263568241).jpg
England rugby team 1905 by Russell & Sons (The Graphic) [Public domain or Public domain]
http://commons.wikimedia.org/wiki/File%3AEngland_rugby_team_1905.jpg
Wandergeselle by Sigismund von Dobschütz [CC BY-SA 3.0]
http://commons.wikimedia.org/wiki/File%3AWandergeselle_02.JPG
Faber-Rechenschieber 5304 by User:Karl Gruber (Own work) [CC BY-SA 4.0]
http://commons.wikimedia.org/wiki/File%3AFaber-Rechenschieber_5304.JPG
Wheel clamps Texas by Richard Anderson from Denton, United States (Boots.) [CC BY-SA 2.0]
http://commons.wikimedia.org/wiki/File%3AWheel_clamps_Texas.jpg
GuadalupeNOLA15Oct07Thanks by Infrogmation of New Orleans (Photo by Infrogmation) [GFDL or CC BY-SA 3.0]
http://commons.wikimedia.org/wiki/File%3AGuadalupeNOLA15Oct07Thanks.jpg
AtariBasic by Calin99 (Own work) [GPL] http://commons.wikimedia.org/wiki/File%3AAtariBasic.png