Software engineering is not an easy profession. You have to constantly learn new things to improve your coding skills and make sure you produce better and cleaner code over time. It’s not difficult, but you have to be aware of a few basic principles. With them in mind you will feel a better engineer and will gain respect from your fellow engineers. And the Lord said: “Thou shall always remember to write unit tests - no matter the deadline. Remember to keep the build green. Thou shall commit often and with meaningful messages (...)”

1. PHP UK
CONFERENCE 2013
Ten Commandments Of A
Software Engineer
Sebastian Marek, Internal Systems Technical Architect

2. ✴ a Pole living in Sheffield
✴ over 12 years in development
✴ Pascal, C++, PHP, perl, python, Java
✴ co-author of 2 PHP Books
✴ big fan of process automation
✴ TDD and CI
@proofek
✴occasionally contributes to open-
source projects
✴ wants to be a knight h"ps://joind.in/8050

5. http://www.flickr.com/photos/archeon/8107633765

6. Couple that work for me
http://www.reverendfun.com/?date=20010207

7. Project cycle phases
Project(
Closure(
ini+a+on(
QA( Design(
(
Implementa+on(

8. Project cycle phases
Project(
Closure(
ini+a+on(
QA( Design(
(
Implementa+on(

9. “I.

10. Thou

11. shalt

12. not

13. disrupt

14.
the

15. legacy

16. system”

17. Problem:
✴ obsolete technology
✴ business critical
✴ poorly documented
✴ change risk
✴ costly maintenance
http://www.flickr.com/photos/tomswift/4253985734/

18. Solution:
✴ extraction
✴ refactoring
✴ blackbox
✴ well defined interface
hp://www.flickr.com/photos/youraccount/3939769126

19. “II.

20. Thou

21. shalt

22. document

23. early

24.
and

25.
while

26. thy

27. mind

28. is

29. fresh”

30. ✴document from the beginning
of the project
✴ developer’s documentation
✓ automated documentation
✓ real world examples
✓ hints and tips
✴ end-user documentation
✓ internal
✓ external
hp://www.flickr.com/photos/jannem/510243975/

31. “III.

32. Thou

33. shalt

34. speak

35. up

36. early

37.
and

38. often”

39. effective communication
✴
within team
✓ trust
✓ weak and strong points
effective communication
✴
within business
✓ communication channels
✓ open and honest
✓ provide options
✴ no decisions vs. bad decisions
hp://www.flickr.com/photos/redspike/5622332401/

40. Project cycle phases
Project(
Closure(
ini+a+on(
QA( Design(
(
Implementa+on(

41. “IV.

42. Designeth

43. not

44. for

45. complexity,

46. but

47. for

48. simplicity;

49.
and

50.
wherever

51. the

52. Beast

53. named

54. Complex

55.
shall

56. rear

57. its

58. ugly

59. head,

60.
smiteth

61. it

62. with

63. thy

64. Sword

65. named

66. Modular,

67.
and

68. let

69. no

70. Module

71. be

72. known

73.
by

74. the

75. Name

76. of

77. the

78. Beast.”

79. hp://www.flickr.com/photos/kelp/4894889826
hp://www.flickr.com/photos/kelp/4894023263
✴ the curse of over-engineering
✴ convention over configuration design paradigm
✴ complex problems are best solved using simple solutions

80. “Make

81. everything

82. as

83. simple

84.
as

85. possible,

86. but

87. not

88. simpler”
hp://commons.wikimedia.org/wiki/Image:Albert_Einstein_Head.jpg

89. “V.

90. Thou

91. shalt

92. not

93. re-invent

94.
the

95. wheel”

96. ✴ repeatable operations
✴ in-house frameworks
✴ open-source frameworks
✴ training and support costs
hp://www.flickr.com/photos/raoulpop/2280399565/

97. Project cycle phases
Project(
Closure(
ini+a+on(
QA( Design(
(
Implementa+on(

98. “VI.

99. Thou

100. shalt

101. commit

102. often

103.
and

104.
your

105. messages

106. shalt

107. be

108. informative”

109. ✴ right tool for the job
✴ commit frequency
✴ commit verbosity
hp://www.flickr.com/photos/27594459@N04/5941708682/

110. Meaningless commit messages

111. Meaningless commit messages
commit 04f1f73b9ad9a2fa968cc3d16701c84f10965e66
Author: Generic Guy generic@email.net
Date: Thu Nov 18 16:16:19 2010 +0000
Initial commit of the entire client application

112. Meaningless commit messages
commit 04f1f73b9ad9a2fa968cc3d16701c84f10965e66
Author: Generic Guy generic@email.net
Date: Thu Nov 18 16:16:19 2010 +0000
Initial commit of the entire client application
commit 38b22c0b4ed15ddf003d6e1d7fb879349a867957
Author: Other Stuff Guy otherstuff@email.net
Date: Mon Nov 22 16:26:27 2010 +0000
Changes to cancel other code

113. Meaningless commit messages
commit 04f1f73b9ad9a2fa968cc3d16701c84f10965e66
Author: Generic Guy generic@email.net
Date: Thu Nov 18 16:16:19 2010 +0000
Initial commit of the entire client application
commit 38b22c0b4ed15ddf003d6e1d7fb879349a867957
Author: Other Stuff Guy otherstuff@email.net
Date: Mon Nov 22 16:26:27 2010 +0000
Changes to cancel other code
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: Verbose Guy verboseguy@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Expand on comment

114. Useless commit messages

115. Useless commit messages
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: Fixed Guy fixedguy@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Fixed

116. Useless commit messages
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: Fixed Guy fixedguy@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Fixed
commit a69657b2045f1105cc940b67bab4b80b0e07ebe9
Author: Did Tests Guy didtests@email.net
Date: Tue Mar 22 15:29:03 2011 +0000
Unit tests to prove the fix

117. Useless commit messages
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: Fixed Guy fixedguy@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Fixed
commit a69657b2045f1105cc940b67bab4b80b0e07ebe9
Author: Did Tests Guy didtests@email.net
Date: Tue Mar 22 15:29:03 2011 +0000
Unit tests to prove the fix
commit af1e80d98c9d8b6fe40efd3eadc27a9d4b1a2420
Author: Failed Codereview Guy
failedreview@email.net
Date: Wed Nov 24 17:07:16 2010 +0000
Code review changes, rename file

118. Informative commit messages

119. Informative commit messages
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: ProperComment Guy propercomment@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Fixed TicketID: Scheduled changes cancelled
without cancelling engineering appointment
Do not let scheduled changes to be cancelled
without calling in, as there is an appointment that
needs to be cancelled

120. Informative commit messages
commit 971704e40b00cbd5fde612ed5aeb96e174bc9d2a
Author: ProperComment Guy propercomment@email.net
Date: Tue Nov 23 16:30:16 2010 +0000
Fixed TicketID: Scheduled changes cancelled
without cancelling engineering appointment
Do not let scheduled changes to be cancelled
without calling in, as there is an appointment that
needs to be cancelled
commit af1e80d98c9d8b6fe40efd3eadc27a9d4b1a2420
Author: ProperComment Guy propercomment@email.net
Date: Wed Nov 24 17:07:16 2010 +0000
Fixed TicketID: Missing data in migration
email
Added the extra variables in the email needed for a
customer migrating from a product

121. “VII.

122. Thou

123. shalt

124. not

125. kill

126.
(maintainability)”

127. ✴coding standards that
everybody follows
✴ keep your code under control
✓ size
✓ complexity
✴ remove dead code
hp://www.flickr.com/photos/brykmantra/76765412

128. “VIII.

129. Thou

130. shalt

131. not

132. repeat

133.
yourself”

134. ✴ copy/paste temptation
✴ clones mutation
✴ extract and reuse ASAP
✴tools that support clone
detection
hp://www.flickr.com/photos/via/6182784051/

135. Project cycle phases
Project(
ini+a+on(
QA( Design(
(
Implementa+on(

136. “IX.

137. Fear

138. not

139. the

140. Priests

141. of

142. Quality

143. Assurance

144.
nor

145. the

146. Altar

147. of

148. Testability,

149.
though

150. they

151. be

152. stained

153. with

154. the

155. blood

156. of

157. thy

158.
brethren;

159.
for

160. they

161. are

162. the

163. Salvation

164. of

165. the

166. Righteous,

167.
and

168. the

169. Servants

170. of

171. our

172. Lord,

173. the

174. Customer.”

175. ✴ manual testing vs. automated
✴ unit tests
✴ functional tests
✴ frequent and early integration
✴ setup CI server
✴ fix bugs ASAP
✴ take ownership
hp://www.flickr.com/photos/alisdair/135306281

177. Project cycle phases
Project(
Closure(
ini+a+on(
QA( Design(
(
Implementa+on(

178. “X.

179. Thou

180. shalt

181. recognize

182. and

183.
retain

184. your

185. top

186. talent”

187. ✴ non fungible people
✴ experience + talent
✴ retention policy
✴ “hit by a bus” vs. “upset and unhappy”
✴people gardening - fertilizers vs. weed
control
hp://www.flickr.com/photos/javacolleen/2897180413/

188. The 10 commandments of a Software Engineer
I. Thou shalt not disrupt the legacy system
II. Thou shalt document early and while thy mind is fresh
III. Thou shalt speak up early and often
IV. Designeth not for complexity, but for simplicity ...
V. Thou shalt not re-invent the wheel
VI. Thou shalt commit often and your messages shalt be informative
VII. Thou shalt not kill (maintainability)
VIII. Thou shalt not repeat yourself
IX. Fear not the Priests of Quality Assurance ...
X. Thou shalt recognize and retain your top talent

192. Further reading
The Ten Commanndments of Software Engineering
✴
✓ http://bit.ly/IgHZTu
The Ten Commandments of Software Quality
✴
✓ http://bit.ly/yJfatp
The Ten Commandments of Egoless Programming
✴
✓ http://bit.ly/atT1F9
✴ http://www.commitlogsfromlastnight.com/

193. Software craftsmanship
Robert C. Martin
@unclebobmartin
✴ http://cleancoder.posterous.com/
✴ http://blog.8thlight.com/
✴ http://cleancoders.com/
✴ http://manifesto.softwarecraftsmanship.org/
✴ http://katas.softwarecraftsmanship.org/

194. hp://www.flickr.com/photos/the-­‐g-­‐uk/7221928760
QA
hps://joind.in/8050