blog.cyber-dojo.org

interviewing and cyber-dojo

Why not ask potential interview candidates to do an exercise in cyber-dojo? Candidates simply email you their cyber-dojo URL (which contains their id) when they're finished. From this you can look not only at their final solution, but also at their tests, and how they got there. We know several companies already doing this. They report that it's best to be clear and up-front about what you want. That it's not uncommon for candidates to work on a solution outside of cyber-dojo and then paste in their final code (and maybe the test code!). This gives you no clue as to how they got there. Ask them not to do this.

Another useful idea is to provide concrete feedback to the candidate and ask them to try again.
Then look at their second submission to see if/how they adopted the feedback.

If your team sometimes pair-programs, why not mirror the pairing in your recruitment process?
Instead of interviewing 5 candidates sequentially, see how five candiates fare technically (and socially) in a 10 person cyber-dojo, pairing each candidate with a developer from the team they're hoping to join. Do several iterations swapping partners each time. Note that if your team never pair-programs it is incongruent to pair in the interview.

Teamwork characteristics ... cannot be determined if you interview ... one at a time.
W. Edwards Deming

lessons from testing

Presented at the excellent Agile On the Beach 2014 conference:

Lessons from Testing from Jon Jagger

some stats on 15,000 practice sessions

As I write this (September 2014) the number of practice dojos on cyber-dojo.org is about 15,000.

The most popular day to run a cyber-dojo is Thursday.

1375 Saturday
1022 Sunday
2488 Monday
2588 Tuesday
2575 Wednesday
2660 Thursday
2307 Friday

The most popular language-unit-test framework is Java-JUnit (but the figures probably depend a lot on which ones have been installed the longest).

3125 Java JUnit
2881 C# NUnit
1087 Python unittest
1071 C++ assert
904 C assert
736 PHP PHPUnit
701 Javascript assert
600 C++ GoogleTest
525 Ruby TestUnit
384 Python pytest
357 Java Approval
324 Java Mockito
278 C++ CppUTest
219 Ruby RSpec
217 Java Cucumber
205 Javascript jasmine
157 Haskell hunit
154 Clojure .test
131 Go testing
125 C++ CATCH
120 Perl TestSimple
...

The most popular exercise is Fizz Buzz (again, some have been installed longer than others).

2091 Fizz Buzz
1830 100 doors
924 Verbal
787 Calc Stats
778 Leap Years
733 Roman Numerals
722 Game of Life
713 Anagrams
644 Print Diamond
549 Tennis
498 Prime Factors
476 LCD Digits
466 Yatzy
405 Bowling Game
355 Count Coins
329 Number Names
298 Harry Potter
287 Mine Field
286 Phone Numbers
192 Poker Hands
...

terms & conditions

cyber-dojo is free for non-commercial use.
Commercial use of the public server requires a license. For example, if you work for a profit-making organization, and you're using https://cyber-dojo.org at work, you need a license.
The cyber-dojo Foundation issues licenses
cyber-dojo is provided in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.

please email us your feedback

What did you like?
What did you dislike?
What should I add?
What should I remove?
Please email your feedback.

how is cyber-dojo implemented?

cyber-dojo.org runs off a Ruby on Rails server, in a docker container, in a Kubernetes cluster.
cyber-dojo's languages also run in docker containers.
cyber-dojo is open sourced and lives on github.
cyber-dojo was conceived, designed, and implemented by Jon Jagger.
cyber-dojo's design is strongly influenced by Jerry Weinberg's teachings on experiential learning.

what is cyber-dojo?

a dojo is a place where martial artists practice martial arts.
cyber-dojo is where programmers practice programming!
cyber-dojo is not an individual development environment.
cyber-dojo is a shared learning environment.
in a cyber-dojo you focus on improving rather than finishing.
in a cyber-dojo you practice by going slower.