I really like the refactoring challenge idea. Any tips on what’s worked or not? Do you do domain specific code or try and keep it generic? I think having them not write code is particularly good way to handle this.
- Showing code is optional. A bit of storytelling to set the scene is enough. So you can keep it generic, or you can add some details, as you wish! Just make sure that the candidate understands the scene. If you present something generic and feel they don't understand, tell it again with more details. If you think you've lost your explanation in details, start over with less details.
- Be sure to know what answer you want. The number 1 thing we want is for the candidate to talk about adding (non-regression) tests. But the candidate can talk about many different things: profiling, tracing, A/B testing of the new implementation, etc. If they don't talk about the #1 thing you want, try to subtly bring them to that point ("how do you ensure that the new implem works as well as the previous one?")
Not specific to the refactoring challenge:
- Ask for feedback. After each challenge, we ask the candidate their honest opinion on the challenge.
- Grasp a feeling of whether or not you'd like to work with this candidate. Try to challenge them, correct them, ask them to explain things in more details and see how they react.
- We do it with 2 interviewers: main and observer (watcher?). Both from the technical team (so 2 devs). We encourage anyone from the tech team to do it if they want, even juniors.
- We do the 3 challenges in 1 hour but that's a bit short. 1h30 would be better, if the candidate is ok with that.
- Showing code is optional. A bit of storytelling to set the scene is enough. So you can keep it generic, or you can add some details, as you wish! Just make sure that the candidate understands the scene. If you present something generic and feel they don't understand, tell it again with more details. If you think you've lost your explanation in details, start over with less details.
- Be sure to know what answer you want. The number 1 thing we want is for the candidate to talk about adding (non-regression) tests. But the candidate can talk about many different things: profiling, tracing, A/B testing of the new implementation, etc. If they don't talk about the #1 thing you want, try to subtly bring them to that point ("how do you ensure that the new implem works as well as the previous one?")
Not specific to the refactoring challenge:
- Ask for feedback. After each challenge, we ask the candidate their honest opinion on the challenge.
- Grasp a feeling of whether or not you'd like to work with this candidate. Try to challenge them, correct them, ask them to explain things in more details and see how they react.
- We do it with 2 interviewers: main and observer (watcher?). Both from the technical team (so 2 devs). We encourage anyone from the tech team to do it if they want, even juniors.
- We do the 3 challenges in 1 hour but that's a bit short. 1h30 would be better, if the candidate is ok with that.