The art of developing more in less time

1. The art of developing
more in less time -
how to not get caught
by long build times?
@EliSawic

2. About me
Eliasz Sawicki
Blog: www.eliaszsawicki.com
Twitter: @EliSawic
www.brightinventions.pl
@EliSawic

3. A short story
about Love
@EliSawic

4. A short story about Love
1. Friendship
@EliSawic

5. A short story about Love
1. Friendship
2. Love
@EliSawic

6. A short story about Love
1. Friendship
2. Love
3. Doubt
@EliSawic

7. A short story about Love
1. Friendship
2. Love
3. Doubt
4. Betrayal
@EliSawic

8. A short story about Love
1. Friendship
2. Love
3. Doubt
4. Betrayal
5. Starting over again
@EliSawic

9. A short story about Love
1. Friendship
2. Love
3. Doubt
4. Betrayal
5. Starting over again
6. Rebuild the trust
@EliSawic

10. How does it end?
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11. Friendship
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12. Objective-C
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13. The UIKit
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14. Why do we need
UIKit?
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15. Love
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16. $wift
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17. Practice
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18. Tests!
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19. Why do we need
tests?
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20. Why do we
have brakes
in a car?
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21. To stop?
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22. To go faster!
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23. Test
Driven
Development
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24. Think
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25. Doubt
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26. Long
build
times
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27. Slow
feedback
loops
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28. No tests
for you today
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29. Betrayal
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30. React Native
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31. Testing feels
natural
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32. Quick reloading
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33. Not a
silver bullet
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34. Starting over again
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35. What was the
problem?
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36. Long
build
times
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37. Slow
feedback
loop
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38. Rebuild
the trust
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39. Tackling
compilation
times
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40. Type
Inference
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41. Type Inference
let viewController = UIViewController()
viewController = UIView() // Nope
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42. Bottleneck
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43. Warnings
-Xfrontend
-warn-long-function-bodies=200
-Xfrontend
-warn-long-expression-type-checking=100
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44. Debug
information
format
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45. With or without you?
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46. DWARF
with
dSYM file?
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47. Take a look at
your build phases
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48. Build phases
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49. Build phases
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50. Build Active Architecture Only
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51. Active architecture
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52. Whole
module
optimization
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53. Drastically decreased
time in which the
project compiles
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54. A catch
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55. A trick
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56. Why isn't it
turned on
all the time?
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57. Managing
dependencies
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58. Cocoapods
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59. Carthage
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60. Build tools
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61. Bazel, Buck
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62. Xcode
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63. Xcode
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64. Xcode settings
defaults write com.apple.dt.Xcode
IDEBuildOperationMaxNumberOfConcurrentCompileTasks 8
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65. Optimizations
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66. Optimizations
• Compilation costs
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67. Optimizations
• Compilation costs
• Don't trust defaults
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68. Optimizations
• Compilation costs
• Don't trust defaults
• Understand tradeoffs
@EliSawic

69. Easy way to decrease
the compilation time
by half
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70. Write smaller apps!
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71. Modularizing
the code
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72. More things to think
about...
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73. Is it bad?
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74. When do we
want to split?
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75. We don't need it
at the beginning
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76. It will be harder later
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77. What should
we do?
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78. Do it later
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79. How do we split?
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80. Don't bite off more
than you can chew
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81. Step
by
step
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82. What is the code
that I write?
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83. We
write
apps!
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84. Do we really
write apps?
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85. Tests!
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86. Why do we compile
the UI code?
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87. Separating
the UI
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88. Is it bad that we
break up
with UIKit?
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89. Nope
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90. MVC
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91. MVC
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92. MVVM
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93. MVVM
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94. Why would you
remove UIKit?
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95. Can be used
anywhere
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96. Can be tested
anywhere
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97. How do we
achieve it?
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98. Passive Views
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99. What is a
passive view?
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100. Logic
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101. Why are they still
together?
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102. Multiple targets
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103. One for UIKit
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104. One for logic
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105. Two for Tests
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106. More things
to handle
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107. Better architecture
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108. Speeded up tests
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109. Faster builds
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110. Modularizing
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111. Modularizing
• Take small steps
@EliSawic

112. Modularizing
• Take small steps
• Use tests as your first client
@EliSawic

113. Modularizing
• Take small steps
• Use tests as your first client
• It's not always worth to modularize
@EliSawic

114. How does the love
story end?
@EliSawic

115. Stronger
relationship
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116. The art of developing
more in less time
@EliSawic

117. How to not get
caught by long build
times?
@EliSawic

118. Time is not the only
issue
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119. The art of developing
more in less time
@EliSawic

120. It's about the
experience
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121. Protect your
feedback loop
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