Presentation for the 18th Encontro Locaweb in Curitiba in May, iMasters' DevCommerce and Open Spree Conference in June. It's about how most developers think wrong whey they are making decisions about technologies to choose.

1. PREMATURE
OPTIMIZATION
The Root of ALL Evil
@akitaonrails

2. @akitaonrails

7. Rubyconf Brasil 2016 – September 23 - 24

8. Rubyconf Brasil 2016 – September 23 - 24

9. September
23 - 24
@rubyconfbr

11. “Premature Optimization
is the Root of All Evil”
- Don Knuth

14. SPA e-commerce

16. SPA e-commerce
http://www.loja.com.br/#!/produtos/item-001

17. SPA e-commerce
http://www.loja.com.br/#!/produtos/item-001
http://www.loja.com.br/?_escaped_fragment_=/produtos/item-001

18. High Level
Numbers

19. Client #1

24. $ 4,000

25. $ 4,000
($ 7 MI/yr revenue - 0.68%)

26. Client #2

30. $ 100,000+

31. $ 100,000+
($ 800 MI/yr revenue - 0.15%)

33. • Minimum IT Cost:

34. • Minimum IT Cost:
• USD 1000 - Cloud Services

35. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer

36. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer
• USD 4000 - 1“Responsible”(Manager, Marketing, etc)

37. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer
• USD 4000 - 1“Responsible”(Manager, Marketing, etc)
• Total: USD 8.000/month (USD 96.000/year)

38. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer
• USD 4000 - 1“Responsible”(Manager, Marketing, etc)
• Total: USD 8.000/month (USD 96.000/year)
• Minimum Business Requirement:

39. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer
• USD 4000 - 1“Responsible”(Manager, Marketing, etc)
• Total: USD 8.000/month (USD 96.000/year)
• Minimum Business Requirement:
• Revenue: > USD 2 MI / year

40. • Minimum IT Cost:
• USD 1000 - Cloud Services
• USD 3000 - 1 Developer
• USD 4000 - 1“Responsible”(Manager, Marketing, etc)
• Total: USD 8.000/month (USD 96.000/year)
• Minimum Business Requirement:
• Revenue: > USD 2 MI / year
• IT Cost / Revenue ratio: < 5%

42. Increase Revenue
>
Lower Costs

44. Open > Proprietary
(prefer“Best of Breed”)

46. Cloud > On-Premise
(Infrastructure/Platform as a Service)

53. SaaS > IaaS
(avoid doing yourself)

56. SEO & SEM
(should not be Astrology!)

58. • /do/you/have/friendly/urls?

59. • /do/you/have/friendly/urls?
• sitemap.xml?

60. • /do/you/have/friendly/urls?
• sitemap.xml?
• Proper HTTP 301 Redirections?

61. • /do/you/have/friendly/urls?
• sitemap.xml?
• Proper HTTP 301 Redirections?
• Social Network buttons?

62. • /do/you/have/friendly/urls?
• sitemap.xml?
• Proper HTTP 301 Redirections?
• Social Network buttons?
• Periodic ORIGINAL CONTENT publishing?

63. • /do/you/have/friendly/urls?
• sitemap.xml?
• Proper HTTP 301 Redirections?
• Social Network buttons?
• Periodic ORIGINAL CONTENT publishing?
• No duplication duplication of content content?

64. • /do/you/have/friendly/urls?
• sitemap.xml?
• Proper HTTP 301 Redirections?
• Social Network buttons?
• Periodic ORIGINAL CONTENT publishing?
• No duplication duplication of content content?
• THEN OK!

66. I.
II.
III.
IV.
V.
VI.
VII.
VIII.
IX.
X.
XI.
XII.
Codebase One codebase tracked in revision control, many deploys
Dependencies Explicitly declare and isolate dependencies
Config Store config in the environment
Backing services Treat backing services as attached resources
Build, release, run Strictly separate build and run stages
Processes Execute the app as one or more stateless processes
Port binding Export services via port binding
Concurrency Scale out via the process model
Disposability Maximize robustness with fast startup and graceful shutdown
Dev/prod parity Keep development, staging, and production as similar as possible
Logs Treat logs as event streams
Admin processes Run admin/management tasks as one-off processes

69. y = x * 320

70. y = x * 320
y = (x << 8) + (x << 6)

72. • NO Test Suite with below 70% coverage

73. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating

74. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating
• NO source code file with hundreds of LOC

75. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating
• NO source code file with hundreds of LOC
• NO COPY AND PASTE EVERYWHERE!!!

76. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating
• NO source code file with hundreds of LOC
• NO COPY AND PASTE EVERYWHERE!!!
• NO functions with more than 1 page down

77. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating
• NO source code file with hundreds of LOC
• NO COPY AND PASTE EVERYWHERE!!!
• NO functions with more than 1 page down
• NO table with dozens of fields

78. • NO Test Suite with below 70% coverage
• NO CodeClimate below 3.0 rating
• NO source code file with hundreds of LOC
• NO COPY AND PASTE EVERYWHERE!!!
• NO functions with more than 1 page down
• NO table with dozens of fields
• NO hours to clone, setup and deploy!!

80. Spree: 68k LOC
40k are Specs! (60%)

81. Magento2: 300k LOC
127k are Specs! (< 30%)

85. Maintainability
>
Performance

88. PRIORITIES!

96. • SQL N+1 Queries

97. • SQL N+1 Queries
• Too much SQL

98. • SQL N+1 Queries
• Too much SQL
• Too much SQL LIKE instead of Elastic

99. • SQL N+1 Queries
• Too much SQL
• Too much SQL LIKE instead of Elastic
• Lack of proper SQL indexes

100. • SQL N+1 Queries
• Too much SQL
• Too much SQL LIKE instead of Elastic
• Lack of proper SQL indexes
• Too much unused code that was not removed

101. • SQL N+1 Queries
• Too much SQL
• Too much SQL LIKE instead of Elastic
• Lack of proper SQL indexes
• Too much unused code that was not removed
• No CDN or proper HTTP Cache invalidation headers

102. • SQL N+1 Queries
• Too much SQL
• Too much SQL LIKE instead of Elastic
• Lack of proper SQL indexes
• Too much unused code that was not removed
• No CDN or proper HTTP Cache invalidation headers
• Too much synchronous work that should be async jobs

103. No Metrics
No Optimization

104. - Alan Kay

105. “Make it Work
- Alan Kay

106. “Make it Work
Make it Correct
- Alan Kay

107. “Make it Work
Make it Correct
Make it Fast
- Alan Kay

108. “Make it Work
Make it Correct
Make it Fast
Make it Cheap”
- Alan Kay

114. You != Unicorn
(nor Facebook, Google, Amazon, etc)

121. 275k Merchants
$ 72 Mi - Q1 2016
Founded: 2004, with Rails pre-1.0

123. Rails works because it
didn’t have Facebook,
Google or Microsoft

124. “Casa de Ferreiro, Espeto de FERRO!”

126. • Increase Revenue > Lower Costs

127. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source

128. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise

129. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise
• SEO & SEM =~ Astrology

130. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise
• SEO & SEM =~ Astrology
• Maintainability > Performance

131. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise
• SEO & SEM =~ Astrology
• Maintainability > Performance
• PRIORITIES!!

132. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise
• SEO & SEM =~ Astrology
• Maintainability > Performance
• PRIORITIES!!
• No Metrics, No Optimization

133. • Increase Revenue > Lower Costs
• “Best of Breed”Open Source
• SaaS > PaaS > IaaS > On-Premise
• SEO & SEM =~ Astrology
• Maintainability > Performance
• PRIORITIES!!
• No Metrics, No Optimization
• You != Unicorn

134. PREMATURE
OPTIMIZATION
is the Root of all Evil

137. THANKS!
www.codeminer42.com
@akitaonrails