Professional Software Development. Can it be taught?

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Professional Software Development Can it be taught? Ivan Zimine PyConSG Edu Summit, 25 Jun 2019

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3 20 years ago… me X

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4 image data: multi-channel multi-slice multi-timepoint Need for custom GUI code

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5 Math, binary logic, and language syntax are the small and easy parts. Small programs are easy to create, but it’s hard to grow and maintain them. Spec/design ﬁrst Lessons learned

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7 1995: Delphi 1996: html, (t)csh, emacs 1997: IDL, bash, latex 1998-2010: IDL, C/C++, bash, perl, python, php, sql, vim, svn/git 2010-2016: python 2016-now: python, ruby, js, java (+ TDD, BDD, CI/CD,…) programming experience (paid)

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9 professional == responsible for outcome

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10 http://disenthrall.co/complexity-is-easy/ Complexity == “software gravity”

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11 https://en.wikipedia.org/wiki/Apollo_Guidance_Computer AGC, 1969 ~100’000 SLOC 1400 person-years Space Shuttle, 1981 > 1’000’000 SLOC Windows NT 3.5, 1993 > 7’500’000 SLOC Mac OS X (tiger), 2007 > 86’000’000 SLOC

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12 0.1 MSLOC ~= 1.5m 10 MSLOC ~= 150m

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13 Invest in communication and social skills (working effectively in teams) Invest in simple tools and pragmatic development practices How to handle complexity?

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14 “ Programs must be written for people to read, and only incidentally for machines to execute.” — Hal Abelson

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15 Proper naming (clarity beats cleverness) - use intention-revealing names - avoid disinformation - use pronounceable names

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16 hello FizzBuzz

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17 refactored FizzBuzz

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18 Linguistics is more important for programming than math! Communicate in code with others Listen to your own code

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19 Executable speciﬁcations are much more useful than requirements docs and architecture diagrams.

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20 Building the right product requires communication with all stakeholders

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Working together: pairing

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“For an idea to go from someone’s head into the computer it must go through someone else’s hands” — Llewellyn Falco Working together: mobbing

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23 Tools: plain text

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24 Tools: command line

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25 Tools: text editor

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26 dev practices: TDD

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27 Can it be taught?

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28 Can it be taught?

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29 Learning is not compulsory… neither is survival. — W. Edwards Deming Thank you ivan@odd-e.com