Android at Scale in Mercari

Talked at Mercari Tech Conference 2018.
Video is here
https://www.youtube.com/watch?v=zVZJSNAsEfE&list=PL5y9uEm8_ypUSnD4TbKKH_7935GxkbgGv&index=7

Transcript

3. 100 ENGINEER TEAM
5. DIFFICULT TO MODIFY
6. DIFFICULT TO MODIFY EASY TO BREAK
7. DIFFICULT TO MODIFY EASY TO BREAK SLOW DEVELOPMENT
9. Israel Ferrer Camacho Android Tech Lead | @rallat
10. Israel Ferrer Camacho Android Tech Lead | @rallat ANDROID @ SCALE
12. QUALITY
13. QUALITY CONSISTENT
14. QUALITY CONSISTENT REUSABLE
15. QUALITY CONSISTENT REUSABLE
16. WHAT IS QUALITY?
17. QUALITY
18. NO BUGS QUALITY
19. PREVENT BUGS WITH TEST QUALITY
20. QUALITY
21. MANUAL TEST QUALITY
22. MANUAL TEST UI TEST QUALITY
23. MANUAL TEST UI TEST INTEGRATION TEST QUALITY
24. MANUAL TEST UI TEST INTEGRATION TEST UNIT TEST QUALITY
25. MANUAL TEST UI TEST INTEGRATION TEST UNIT TEST QUALITY
26. QUALITY UNIT TEST
27. QUALITY Easy to write UNIT TEST
28. QUALITY Easy to write Easy to maintain UNIT TEST
29. QUALITY Easy to write Easy to maintain Fast to run UNIT TEST
30. Run unit test for each commit Immediate quality feedback! For engineers is a safety net QUALITY UNIT TEST
31. Feature proofs the code for future changes QUALITY UNIT TEST
32. QUALITY CONSISTENT REUSABLE
33. QUALITY CONSISTENT REUSABLE
34. DEFINE PRINCIPLES CONSISTENT
35. PRINCIPLES CAN EVOLVE CONSISTENT
36. CONSISTENT NEW ARCHITECTURE
37. CONSISTENT LAYERED ARCHITECTURE
38. CONSISTENT SINGLE RESPONSIBILITY
40. View layer
41. View layer Logic layer
42. Data layer View layer Logic layer
43. View layer Data layer Logic layer
44. View layer Data layer Logic layer
45. View layer Data layer Logic layer
46. View layer Data layer Logic layer
47. REUSABLE?
48. BUSINESS LOGIC REUSABLE
49. USE CASES LAYER REUSABLE
50. Use cases View layer Data layer Screen behavior
51. View layer Data layer Sort Items Buy Item Like Item Comment Item Screen behavior
52. Use cases View layer Data layer Screen behavior
53. Use cases View layer Data layer Screen behavior
54. Use cases Screen behavior View layer Data layer
55. Use cases Screen behavior View layer Data layer QUALITY
56. Use cases Screen behavior View layer Data layer QUALITY CONSISTENT
57. Use cases Screen behavior View layer Data layer QUALITY CONSISTENT REUSABLE
58. HOW TO REUSE CUSTOM VIEWS, COMPONENTS, UTILS?
59. DISCOVERABILITY?
60. HOW CAN 100 ENG WORK IN THE SAME CODEBASE?
61. REUSABLE
62. MONOLITHIC 
 REUSABLE
63. MONOLITHIC 
 MONOLITHIC TO
 MODULAR REUSABLE
64. 4DSFFO
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65. . 4DSFFO
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66. REUSABLE . 4DSFFO
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67. 6*$PSF REUSABLE . 4DSFFO
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68. REUSABLE . 4DSFFO
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69. REUSABLE . 4DSFFO
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70. REUSABLE . 4DSFFO
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71. REUSABLE . 4DSFFO
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72. REUSABLE . 4DSFFO
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73. REUSABLE . 4DSFFO
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74. REUSABLE . 4DSFFO
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75. REUSABLE . 4DSFFO
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76. REUSABLE 4DSFFO
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77. REUSABLE 4DSFFO
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78. REUSABLE 4DSFFO
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79. REUSABLE 4DSFFO
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80. REUSABLE 4DSFFO
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81. ADVANTAGES MODULAR
82. ADVANTAGES MODULAR
83. ADVANTAGES MODULAR Improve reusability
84. ADVANTAGES MODULAR Improve reusability Improve discoverability
85. ADVANTAGES MODULAR Improve reusability Improve discoverability Less code conflicts
86. ADVANTAGES MODULAR Improve reusability Improve discoverability Less code conflicts Faster build time in Gradle
87. MERCARI MODULES
88. REUSABLE
89. REUSABLE Core
90. REUSABLE Core Identity
91. REUSABLE Core Identity Util
92. REUSABLE Core DB Identity Util
93. REUSABLE Core Network DB Identity Util
94. REUSABLE Core Network DB Identity Core-java Util
95. REUSABLE Core Network DB Identity Core-java Android Core Util
96. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android
97. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android Model
98. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model
99. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features
100. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features Search
101. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features Live Search
102. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features Live Offer Search
103. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features Live Offer Payment Search
104. REUSABLE Core Network DB Identity Core-java Android Core Util Util-Android UI Model Features Live Offer Payment Search Listing
106. QUALITY
107. QUALITY CONSISTENT
108. QUALITY CONSISTENT REUSABLE
109. HOW LONG?
110. THIS IS NOT A TEMPORARY PROJECT
112. NOT A SOLO PROJECT
114. LONG LASTING CHANGE ENGINEERING CULTURE
115. FROM CODER
116. FROM CODER TO ENGINEER
117. ENGINEER CODER
118. ENGINEER CODER Writes Code
119. ENGINEER CODER Writes Code Writes Code
120. ENGINEER CODER Writes Code Writes Code Code reviews
121. ENGINEER CODER Writes Code Writes Code Code reviews Best solution for a problem
122. ENGINEER CODER Writes Code Writes Code Code reviews Best solution for a problem Cares about Performance
123. ENGINEER CODER Writes Code Writes Code Code reviews Best solution for a problem Cares about Performance Cares about Quality
124. ENGINEER CODER Writes Code Writes Code Code reviews Best solution for a problem Cares about Performance Cares about Quality Feedback to the Team
125. ENGINEER CODER Writes Code Writes Code Code reviews Best solution for a problem Cares about Performance Cares about Quality Feedback to the Team Feedback to the product
126. HOW?
127. WRITE A PROPOSAL
128. WRITE A PR WITH EXAMPLE
129. COLLABORATIVE WORK
130. WRITE GUIDELINES
131. COLLABORATIVE WORK
132. TRAIN THE TEAM
133. OFFICE HOURS
134. PAIR PROGRAMMING
135. CODE REVIEWS
136. RESULTS
137. NEW ARCHITECTURE QUALITY 100% Adoption in new features
138. CODE COVERAGE QUALITY
139. 0 5 10 15 20 June July August Sept CODE COVERAGE QUALITY
140. 0 5 10 15 20 June July August Sept CODE COVERAGE QUALITY
141. STRONG ENGINEER
142. CREATE BETTER PRODUCTS
143. THANKS! JOIN US! Challenge awaits you!