OO sessions. Learning from failed interviews.

OO Sessions

Earlier this week i did a session with a candidate looking for a job with ThoughtWorks. It was a little strange as she had already failed our coding test, but she was otherwise a really strong candidate. RM asked if she would like to have a session with a couple of us here so we could point her in the right direction (coding wise) and then she may re-apply in six months or so.

She had 3 years experience in .net, mainly writing windows forms applications, and in her eyes had produced some good object orientated code for her submission.

Coding challenges

We (ThoughtWorks) give candidates coding challenges to complete before interview so that we can more accurately asses programming skill. From the spec she had pulled out a good domain model for the problem consisting of 4 or 5 classes which reflected the simple domain quite well. There were attributes on these classes to represent the fields and collections, and also this was all quite well tested. But... this was very much a microsoft approach.

View logic, code behind

All the logic lived in the view of the windows form app. the code behind class had responsibility for everything, from reading files to processing, validation, sorting, and output formatting. None of the methods on this class were tested, in fact none were testable as everything depended on everything else, you had to spin up the app to run it, maybe thats why there were no tests.

Learnings

What struck me though was how intelligent the candidate was. It was great to see that after one and a half hours of discussing her code submission how she now views OOP. How behavior is part of the domain, how utility classes should be part of the domain, and how to unit test things properly. It was great to know we had imparted knowledge on her and that she was excited by what she had learned.

I place a lot of the blame on both Microsoft (for producing simplistic code examples for simple problems, which people then copy) but more so her peers, senior technical folk and technical leaders. These are the people you learn your craft from, these people should be able to develop better solutions than the simple code samples you see all too often in online tutorials. Had they mentored her in a better way she would not just be finding out how to do this stuff after 3 years.

I do hope she does reapply, i liked her and agree with RM that she has lots to offer, just learn a little more OO coding first. Its great that we (TW) are given the opportunity to teach like this. She was not joining the company. She had already failed the interview process. She may join in the future but thats not the point, the point was we did this for free, giving something back, it was great. And I hope everyone i meet who lacks a bit of knowledge or skills is as open as her to different ideas and different ways of doing things. I hope i am.