Break the Monolith!

If you have a large monolith, built over many years and supported by multiple teams, delivering ambitious features, moving to the cloud or migrating to modern technologies are hard challenges.
A great way to approach that challenge is through a judicious and progressive modularization of the components, teams and products. But such an approach is not self-evident: How to cut judiciously, and at what pace? How to manage the inevitable interactions between the parts? How to preserve the objectives of the organization as a whole despite the division? What are the pitfalls to avoid, and what are the opportunities?

This session will provide pragmatic answers based on several years of practice with numerous companies, on top of the state of the art, and all this with a vision of architecture that bridges the gap between the technical, social and business challenges.

Transcript

1. @CYRIUX BREAK THE MONOLITH! CHALLENGES & OPPORTUNITIES @CYRIUX @AROLLAFR Cyrille Martraire
2. @cyriux @arollafr You must be able to deploy anytime!
3. @cyriux @arollafr You have to scale the delivery!
4. @cyriux @arollafr You have to be full cloud- native!
5. @cyriux @arollafr You have to go full microservices!
6. @cyriux @arollafr If only it was THAT simple…
7. @cyriux @arollafr If only I didn’t have this big monolith!
8. @CYRIUX BREAKING A MONOLITH? @CYRIUX @AROLLAFR
9. SINCE 1999 CYRILLE MARTRAIRE @CYRIUX @AROLLAFR CO-FOUNDER & CTO AROLLA DEVELOPER, CONSULTANT, TRAINER FOUNDER PARIS SOFTWARE CRAFTERS SPEAKER & AUTHOR
10. arolla.fr @arollafr TDD | BDD | DDD
11. arolla.fr @arollafr crafting architecture
12. @CYRIUX BREAKING A MONOLITH? @CYRIUX @AROLLAFR
13. @CYRIUX BREAKING A MONOLITH? @CYRIUX @AROLLAFR
14. MONOLITH = 1
15. @CYRIUX 1 COMPONENT {;}
16. @CYRIUX 1 TEAM
17. @CYRIUX 1 GROUP?
18. @CYRIUX 1 REPO #Commit
19. @CYRIUX DEPLOY AT ONCE #GoLive
20. @CYRIUX INITIALLY: SMALL
21. @CYRIUX INITIALLY: HAPPINESS
22. @CYRIUX …
23. @CYRIUX EVENTUALLY: LARGE #sad
24. @CYRIUX EVENTUALLY: FRUSTRATION #sad
25. @CYRIUX MANY RESPONSIBILITIES IN ONCE PLACE #notSRP {;} {;} {;} {;} {;}
26. @CYRIUX TOO MANY PEOPLE
27. @CYRIUX INTERFERING ON EACH OTHER’S WORK
28. @CYRIUX OR TOO MUCH COORDINATION #TooManyMeetings
29. @CYRIUX SLOW DELIVERY #Slow
30. @CYRIUX MANY OTHER ISSUES #scaling-as-1-piece #not-cloud-native #excessive-coupling
31. @CYRIUX FRUSTRATION #sad
32. @CYRIUX BUT MONOLITH IS NOT A DIRTY WORLD
33. @CYRIUX NOTHING’S WRONG WITH A SMALL MONOLITH Laårk Boshoff
34. @CYRIUX NOTHING’S WRONG WITH A STRUCTURED MONOLITH Paul Hanaok a
35. @CYRIUX LARGE AND ENTANGLED IS THE ISSUE
36. @CYRIUX BREAK THE MONOLITH @CYRIUX @AROLLAFR
37. @CYRIUX MAKING THE MONOLITH MORE MODULAR @CYRIUX @AROLLAFR
38. WHY BREAKING A MONOLITH? TOO BIG FOR ONE TEAM TOO BIG TO SCALE WELL TOO BIG FOR THE CLOUD SCALING TEAMS SCALING RUNTIME CLOUD-FRIENDLY
39. @CYRIUX MANY MODULES @CYRIUX TOO BIG FOR ONE TEAM {;} {;} {;} {;}
40. @CYRIUX MANY TEAMS @CYRIUX TOO BIG FOR ONE TEAM
41. @CYRIUX GRANULAR SCALING @CYRIUX S XXL M XL TOO BIG TO SCALE WELL
42. @CYRIUX GRANULAR ELASTICITY @CYRIUX 0..1 1-∞ managed (function) TOO BIG FOR THE CLOUD managed reserved 3
43. WHY BREAKING A MONOLITH? TOO BIG TO REWRITE TOO BIG TO FIT IN YOUR HEAD PROGRESSIVE MODERNIZATION BETTER IMPACT ANALYSIS
44. @CYRIUX GRANULAR MODERNIZING @CYRIUX partial rewrite TOO BIG TO REWRITE partial rewrite partial rewrite partial rewrite
45. @CYRIUX HUMAN-SIZED @CYRIUX small TOO BIG TO FIT IN YOUR HEAD small small small #less-to-learn #fewer bugs
46. @CYRIUX @CYRIUX TOO BIG TO FIT IN YOUR HEAD HUMAN-SIZED
47. @cyriux @arollafr Ok, now split it into modules!
48. @cyriux @arollafr If only it was THAT simple…
49. @CYRIUX @CYRIUX ?
50. @cyriux @arollafr @cyriux
51. @CYRIUX @CYRIUX
52. @CYRIUX @CYRIUX
53. @CYRIUX @CYRIUX
54. @CYRIUX @CYRIUX #EvenMoreMeetings
55. @cyriux @arollafr @cyriux
56. @cyriux @arollafr @cyriux
57. @CYRIUX @CYRIUX #AutonomyByDesign
58. @CYRIUX HOW TO DECIDE THE BOUNDARIES?
59. @cyriux @arollafr @CYRIUX
60. BOUNDED CONTEXTS @CYRIUX
61. BOUNDED CONTEXTS @CYRIUX since 2003
62. BOUNDED CONTEXTS @CYRIUX before it was cool
64. in autonomy
65. @CYRIUX HOW NOT TO HOW TO @CYRIUX
66. @cyriux @arollafr NO
67. @cyriux @arollafr YES
68. @CYRIUX HOW NOT TO @CYRIUX
69. Split by layer W eb Logic Dao DB EASY & WRONG
70. Split by tech Mongo Postgres Elastic EASY & RANDOM
71. Split by entity Client Purchase Product EASY & WRONG
72. Split by Screen EASY & WRONG Hom e My Account DrillDow n
73. Split by Billable unit EASY & WRONG Core Prem ium
74. @CYRIUX HOW TO @CYRIUX
75. Split by Functional Area aym ent atalogue hipping Billing NOT SO EASY
76. TECHNICAL DECISION Functional areas
77. TECHNICAL DECISION Functional areas
78. TECHNICAL DECISION Functional areas
79. @CYRIUX Focus on the language @CYRIUX
80. Payment Event Anomaly Agent Transaction Transaction Status Account Basket Items Recent Baskets
81. Payment Event Anomaly Agent Transaction Transaction Status Account Basket Items Recent Baskets
82. Payment Event Anomaly Agent Transaction Transaction Status Account Basket Items Recent Baskets Shopping Cart Payment Payment Fraud Detection
83. Payment Event Anomaly Agent Transaction Transaction Status Account Basket Items Recent Baskets Shopping Cart Payment Payment Fraud Detection purpose = be Paid purpose = Sell purpose = Avoid loss
84. @CYRIUX Focus on the purpose @CYRIUX Sub-domain names as verbs made into nouns: often end in -ing or -tion or -ment
85. Payment Event Anomaly Agent Transaction Transaction Status Account Basket Items Recent Baskets
86. THE SAME THING IN THE REAL WORLD (EG A CUSTOMER) FOR DIFFERENT PURPOSES BECOMES DIFFERENT THINGS
87. DIFFERENT THINGS purpose = Sell purpose = Avoid loss Potential Fraudster ”Wanna be buyer”
88. @CYRIUX Mixing All Your Mental Models @CYRIUX Interviews. Code reviews. Collaborative workshops.
89. EVENT STORMING
90. Pre-Negotiation Listing) B2BOrdering Fraud Détection Payment Sourcing Distribution Rates Grid RealTime Prices Gift Cards Content & Comparators Sales Promotion Acquisition TV Campaigns Online Ads Company Rating Product Reviews Shopping Cart Catalogue Search Categories Tags Partnerships Secondary Listing Internal Purchasing Rates CrossSales Navigation SEO Marketing MAPPING THE POTENTIAL BOUNDED CONTEXTS
91. Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable MAPPING THE POTENTIAL BOUNDED CONTEXTS
92. @cyriux @arollafr
93. @CYRIUX NOW THAT WE FOUND THE BOUNDARIES, WHAT ARE WE GONNA DO WITH THEM?
94. @CYRIUX BREAK THE MONOLITH FOR REAL! @CYRIUX @AROLLAFR
95. Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable SpringBoot Postgres / Elastic Search RabbitMQ Microservice MODULE = MICROSERVICE (BACKEND)
96. MODULE = MODULE IN MONOLITH Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable Modular Monolith ”Majestic Monolith”
97. Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable Node.js Elastic Search RabbitMQ BFF MODULE = FRONT MICROSERVICE (BFF)
98. Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable (Function) (Function) (Function) Serverless store Serverless bus FaaS / BaaS / SaaS MODULE = FUNCTIONS / SERVERLESS SERVICES
99. Mapping the Potential Bounded Contexts Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Audience Experiences Business (Sub)- Domains Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable legacy components not aligned (at all)
100. @CYRIUX GUIDING DELIVERY PROJECTS @CYRIUX Don’t split for the sake of it. Split Opportunistically when needed. Never fully done.
101. @CYRIUX (Like Cellular Division)
102. @CYRIUX (Like Cellular Division)
103. @CYRIUX LIMITS & CONSEQUENCES
104. @cyriux @arollafr But modules work with each other!
105. @CYRIUX @CYRIUX Contracts Everywhere STABLE CONTRACTS ENABLE BOTH SIDES TO CHANGE FREELY
106. @cyriux @arollafr If they work together, they must be coupled!
107. @CYRIUX microservices Event-Driven Architecture API’s Smart Endpoints, Dumb Pipes @CYRIUX Choreography over Orchestration Change-Ready Architecture
108. Event Bus / Observer pattern Ticke t Booked Bookin g Service Bookin g Confirmed Inventor y Service Bookin g Cancelled Capacit y Updated Ticketin g Service CHANGE IN ONLY 1 PLACE
109. Event Bus / Observer pattern Ticke t Booked Bookin g Service Bookin g Confirmed Inventor y Service Bookin g Cancelled Capacit y Updated Ticketin g Service Notificatio n Service CHANGE IN ONLY 1 PLACE
110. Event Bus / Observer pattern Ticke t Booked Bookin g Service Bookin g Confirmed Inventor y Service Bookin g Cancelled Capacit y Updated Ticketin g Service CHANGE IN ONLY 1 PLACE
111. @cyriux @arollafr But it’s silos again!?
112. HIGH-LEVEL ALIGNMENT OWN INTELLIGENCE + LOCAL KNOWLEDGE TO ACT COMPANY VISION & GOALS HIGH- LEVEL STRATEGY (HIGH LEVEL)
113. @cyriux @arollafr But the global optimum isn’t the sum of local ones!
114. @CYRIUX @CYRIUX ‘FINE TUNING’ CONTROL LOOPS LOW-FREQUENCY
115. @cyriux @arollafr But we already moved to the cloud!
116. @cyriux @arollafr fedakv.medium.com/ GRANULARITY MATTERS
117. @CYRIUX MORE OPPORTUNITIES…
118. Modularity opens options @CYRIUX
119. MODULAR PERSONAL COMPUTER
120. @CYRIUX GLOBAL OPTIONS @CYRIUX
121. @CYRIUX GLOBAL OPTIONS @CYRIUX A
122. @CYRIUX GLOBAL OPTIONS @CYRIUX A’
123. @CYRIUX GLOBAL OPTIONS @CYRIUX A’ X
124. @CYRIUX @CYRIUX ”PAIN AU CHOCOLAT” LOCAL OPTIONS ”CHOCOLATINE”
125. @CYRIUX @CYRIUX EXTREME PROGRAMMING LOCAL OPTIONS KANBAN SCRUM
126. @CYRIUX @CYRIUX LOCAL OPTIONS POSTGRES POSTGRES POSTGRES POSTGRES
127. @CYRIUX @CYRIUX TDD, BDD, DDD, 90+ COVERAGE LOCAL OPTIONS CHANGE CHEAP, 40% TESTS FROM NOW ON KEEP AS-IS, TEST MANUALLY AS USUAL
128. CRAFT IS NOT EVERYWHERE, ALL THE TIME?!
129. BE CAT-MATIC NOT DOG-MATIC
130. @CYRIUX Escape the Tyranny of ONE @CYRIUX Everything is contextual. No one-size- fits-all.
131. @cyriux @arollafr Fraud Détection Payment Gift Cards n mpany ting Review Shopping Cart EVENT-SOURCED HEXAGONAL ARCHITECTURE CRUD SaaS
132. @cyriux @arollafr Fraud Détection Payment Gift Cards n mpany ting Review Shopping Cart POstgres POSTGRES S3+RDS Elastic
133. @cyriux @arollafr Fraud Détection Payment Gift Cards n mpany ting Review Shopping Cart Azure API APP on-premise Azure/WEbapp SaaS Azure FUNCTIONS Azure ML
134. @CYRIUX GRANULAR EVERYTHING @CYRIUX S XXL M XL TOO BIG TO BENEFIT FROM THE CLOUD
135. @cyriux @arollafr Fraud Détection Payment Gift Cards n mpany ting Review Shopping Cart REWRITE outsource KEEP AS-IS KEEP EXTRACT EXTRACT AS LIB
136. @CYRIUX GRANULAR SCALING @CYRIUX repair rewrite extract rewrite TOO BIG TO REWRITE
137. @CYRIUX EVEN MORE OPPORTUNITIES
138. REPORTING À LA MAP-REDUCE REDUCE MAP MAP MAP MAP REDUCE REDUCE REDUCE REDUCE LOCALLY COMPUTED LOCAL METRICS AGREGATED GLOBAL METRICS
139. BOUNDED CONTEXTS IN A VALUE CHAIN Sub-Domain A sub-sub domain A1 sub-sub domain B1 sub-sub domain C1 Domain Sub-Domain B Sub-Domain C sub-sub domain A2 sub-sub domain C2 Customers Experience X1 Customers Experience X2 Customers Experience X3 Generic enabler Domain- agnostic Enablers Collaborators Experience X4 Very specific Generic Specific audience Domain- Specific Domain- Agnostic Volatile Stable Self-care ratio Conversion rate acquisition cost Average Basket Amount Turnover = Traffic x conversion rate x average basket
140. @CYRIUX MODULAR COMPANY @CYRIUX
141. @CYRIUX @CYRIUX MODULAR SYSTEM PLATFORM VALUE- ADDED SERVICES INNO- VATION
142. @CYRIUX @CYRIUX ECO-SYSTEM PLATFORM VALUE- ADDED SERVICES INNO- VATION EXTERNAL BUSINESSES EXTERNAL INNOVATIONS
143. @CYRIUX @CYRIUX MERGER, ACQUISITION PLATFORM VALUE- ADDED SERVICES INNO- VATION BEST-OF-CLASS, BY SUB-DOMAIN BUY INNOVATION
144. @CYRIUX @CYRIUX SPIN-OFFS PLATFORM VALUE- ADDED SERVICES INNO- VATION
145. @CYRIUX @CYRIUX PIVOT PLATFORM VALUE- ADDED SERVICES INNO- VATION FOCUS HERE GIVE UP GIVE UP
146. GREGOR HOHPE ”ARCHITECT ELEVATOR”
147. CONNECT BUSINESS STRATEGY TO TECH & VICE-VERSA
148. @cyriux BUY MY BOOK!
149. @cyriux BUY our BOOK!
150. @CYRIUX WHY AND HOW WOULD YOU BREAK YOUR MONOLITH THEN?
151. @CYRIUX THE END THANK YOU @AROLLA @LESINGECUIVRE