Technical practices like refactoring and TDD (Test-Driven Development) have become mainstream in software development. However, software developers I met in many companies are either oblivious or have a different interpretation. My interest is to help developers adopt technical practices and being a mentor has played a big part. Through the years I've tried many ways to maximise the effectiveness of mentee's learning and also brings many challenges and discoveries. In this talk, I'll share the experiments I tried and hope it'll inspire you to help others improve their technical practices.

1. Technical Mentoring
What works and not
stanly@odd-e.com
@stanlylau

2. Lives in Singapore
Software development coach / mentor
Agile Singapore 2013, 2014, 2016

3. http://www.marketingfirepower.info/the-minefield-you-didn’t-know-you-were-in

4. Code Smells &
Refactoring

5. Original program:
Making changes:
More changes:
Without refactoring With refactoring
Small change
Refactor
Etc

6. Mentoring
“A structured self-development method that provides
support to help individuals manage their own learning
and realize their full potential. It is out of the reporting
line, where the experience gap (not the status gap) and
the mentee drive the relationship.”
Parsloe, 2000; Clutterbuck, 2004

7. Experiments
(informal)

8. TDD workshop followed by pairing
with team members for two weeks
Tried
• 70% lectures, 30% exercises
• Code exercises from public
• Pairing happens random
Learned
• Pairing related to code were slim
• Assess the current state of automated build
• Some people were defensive

9. Tried
• StringCalculator exercise
• 20 people, most are new to TDD
Learned
• Most have trouble writing test first
• Questions of applying on their existing systems
• What if we focus only on refactoring first?
Community Mini-Coderetreat

10. Refactoring Kata

12. Refactoring Kata
Outcome
• They felt confident changing code
• Inspired them to add tests at work
• They added and was unmaintainable

13. One-on-one Mentoring
Tried
• Prepare a few topics
• Share with me their reflection/learnings
Learned
• Don’t know where to start in long method
• Draw/Model the classes
• Skills often mentioned

14. One-on-one Mentoring
Common mentioned skills
• Hotkeys
• Understanding Single Responsibility Principle
• Return null vs empty list
• Refactor multiple returns to single return
• Distance of behavior and data (domain object)
• Working with 3rd party webservice API
• Name closer to the business language

15. Tried
• Remove mines on larger minefield
• More guidance at the beginning & more questions later on
• Ruby on Rails + Travis CI + Heroku + Github
• Topics widen to continuous delivery
Learned / Outcome
• More than half picked up fast
• A few were inspired by the special project
• Prod. release takes < 30 minutes instead of a day
2-week Mentoring with Senior Developers

16. Four Stages of Competence
https://en.m.wikipedia.org/wiki/Four_stages_of_competence

17. • Start with Code Smells & Refactoring Workshop
• Code exercises from product’s codebase
• Series of progressive one-day workshops
• One-on-one sessions between workshops
• Hands-on exercises then debrief
• Maximum of 8 participants
• Two co-leaders, me & another from the company
• Platform for growing mentors
Technical Training Program

18. Anonymised

19. • One week of preparation
• More than 10 exercises
• Remove code smells always
• Context limited to within the method
• Repetition + little different
• Respectfully intrude and challenge
Refactoring Workshop #1

22. What aspects of the course were most
successful in helping you to learn?
“Use Resharper hotkeys”
“Use real production code to practise”
“Approach towards a problem, especially all those
shared examples are very commonly seen code
smells.”

23. What improvements to the course do you
suggest?
“More examples on how to identify code smells such
as primitive obsession”
“Sometimes I am lost after the trainer expect me to do
the refactoring on the code”
“More sessions"

24. • More than one week of preparation
• 7 exercises
• Context includes callers and call-ees
• Lesser repetition
• New code smells
• Characterisation tests
• Simplify code using library e.g. JSONConvert
• Model/Draw the classes and interactions
Refactoring Workshop #2

26. What aspects of the course were most
successful in helping you to learn?
“Hands on, new library feature introduction”
“Explanation on speculative generality with diagrams”
“Trying out by ourself how to identify and refactor”

27. What improvements to the course do you
suggest?
“No comment. But look forward for more workshops
like this in future.”
“More practice examples to be more familiar in
recognizing and tackle the similar code smell.”
“Give some starters before getting our hands dirty.
Some of us might not be that creative and might not
be able to make full use of the allotted time.”

28. Assignments as a Pre-requisite
Tried
• Part 1: Review a recent code that was refactored
• Part 2: Remove the smells in a refactoring kata
• I’ll respond with my thoughts about their code
Learned / Outcome
• Excellent way to find out where they are
• Opportunity to hear their thoughts

29. Assignments as a Pre-requisite
“Actually I knew this code smell in my code but I
don’t know any good way to remove this smell, so I
hope I can attend workshop #2 to learn more about
refactoring.”

30. How many workshops does it take to
reduce the smells in commits?
?

31. Summary

32. What works
• Facilitative mentoring for effective learning
• Skill to assess where individuals are
• Appropriate challenge for progressive learning
• A structure to facilitate follow up
• Derive exercises from existing codebases
• Engage and grow internal mentors
What’s not
• Workshop/Training alone is insufficient
• Weak self-awareness of communication style

33. Thank you
stanly@odd-e.com