Ask HN: What's an effective programming test? | Hacker News Reader

Ask HN: What's an effective programming test?

6 pointskator7 comments

For a medium to senior level position do you expect to work on a problem that could take several hours to develop (plus the test harness, etc. etc.)?

Any suggestions on developing a good test for medium to senior level developers?

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The best code challenge I was given was to build an infinite scroll implementation. The company gave me an API endpoint that spat out JSON, and my assignment was to create a page that would show the items and render more items from the endpoint when you scroll down to the bottom of the page. I was given no time limit. They just said "send us the code in email when you're done". I was allowed to use anything I wanted. I finished in about 6 hours. Most of the time was spent going through the bajillion endless scroll jquery plugins (99% of all jquery plugins are total crap). It was fun for me, and I was allowed enough time to polish up the code to get it looking like code I normally write. Now if I ever want to implement infinite scroll in any of my personal projects, I know how to do it.

The worst code challenge I was given was by a company that basically gave me a huge dump of data (a 60 line string in a very peculiar format) and told me to write a function that took the data, processed it, then outputted that data in another peculiar format. I was given one hour to complete this assignment. It was tedious and in no way fun, so I just didn't do it. I probably could have gotten it, but I don't like doing things like that. If the interview contains high-stress speed coding, then I can only assume the job contains the same. No thanks.

Good developers like to take their time, so don't timebox (at least not in units of hours, a one week deadline is fine). Also, good developers don't like doing tedious things. Give them something meaningful to do, not just busywork.

I think a programming assignment is effective at determining how they can perform in a real-world setting. Let them use the internet and any other resources they want (except of course plagiarism), and give them a couple of hours of alone time. An example of an problem I've seen is to implement a program that suggests spelling corrections given a dictionary file and a word. It's simple and easy to understand.

>give them a couple of hours of alone time

are they allowed to delegate parts of the task to others?

No plagiarism? Why not? If s/he can download a piece of open source software that can do the job, I would call that a pretty successful test. That's what a good developer would do on the job. And it isnt plagiarism if s/he leaves in the original copyright/whatever.

This isn't a literal simulation of real-life work, it's a programming test. Certainly gluing together free components is an important skill for any developer, but I would expect anyone interviewing for a medium to senior level position to be able to trivially do that.

Sit them down in fron tof your system. Have them work on something. If they ca nmanage to pull through, hire them. If not, don't. If your system is so finicky that a newcomer can take down, then having this person break it for you will allow for a stronger system to be built. I don't get the fascination with asking stupid interview questions. Sit the person in front of a computer, have them look at your code, have them write some code, and then have them explain the code. After all, it is that very same code what they will be working with. Why not show it right from the start? To add, most applications out there are just front ends to databases. Why do they need to know X or Y? All they need to know is how to write a query and process the results. No big deal.

I guess the bigger question I have is how much time to you think is reasonable? I recently did a test one of my clients uses and to do it "right" took many hours.. but I also built test scripts, makefile, time testing scripts etc. But still I wonder what people think is reasonable?

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