Test tasks for potential web developer employees?

I’m currently interviewing for a new developer. I’m met a couple that seem to know what they’re talking about. My next step would normally be to set them some minor coding task to do over the weekend, so I can see what kind of code they produce.

The job is general web developer, so PHP, MySQL, HTML, CSS, javascript are required skills.

Last time I did this I asked them to do a simple log in script, and didn’t judge much else apart from protecting themselves from sql injection (one guy didn’t and was disqualified).

Any suggestions as to a task to set and what to judge them on?

You could just get them to do pseudo code and give them something a little bigger.
The idea of doing a log in form and judging if they prevented against sql-injection is good!

I am assuming that each of the programmers knows enough about programming to get them by (since they made it through the interview and have some kind of intelligence).

But it’s really easy to learn the programming side of things (straight language knowledge). I was doing it at 6 years old. And it’s easy enough to pick up a refresher on a function name, or whatever. How many times have you Googled a function quickly because you just needed to be reminded of the parameter count or order?
What you want to be sure (and is much harder to teach) are things like best practices (like SQL-injection—lazy programmer to skip that!), creativity, thoroughness and adaptability.

I’d ask them to quickly outline an update page with various fields given from a database. You’ll find out quickly a lot of things. If they’re skipping things like SQL-injection, validation, if they have more than a fleeting knowledge (using things like filters or using depricated ereg replaces or something !). You’ll also see if they have OOP skills or OOP thinking at least. Give them a quick example of the level of pseudo code you’re looking for.

But lots of that can be accomplished in interview too. The things you work on in house - ask them how they would deal with that.
“You need to create a page which allows our customer to update entries in a database. How would you protect that database from accidental or purposed corruption?”, “How would you validate the user’s input?”, “How would ensure that the page could be update in the future easily, by someone else?” - But give prompts when necessary.

I can answer specifically with regards to front-end developers. When I interview I usually send them a PSD to cut up before they interview… just something simple that requires them to build a CSS based layout and I suggest they may add some interactivity with JavaScript and note some assumptions and exclusions (like, links don’t have to go anywhere, javascript libraries are allowed etc).

The reason I get them to cut it up before I interview is because if someone writes really bad code, I probably don’t want to waste my time interviewing them.

What I usually look out for is:

[]They understand CSS based layouts well (in fact, Table based layout = no interview)
]Importantly, they modularise their code
[]Well formatted code
]Semantic markup / classes / IDs etc.
[]If they used JavaScript that it’s done in a “friendly” manner (degrades gracefully or progressively enhances)
]Bonus points for:

  • Paying attention to accessibility
  • Suggesting improvements
  • Making it work in IE6
  • Comments where applicable

[/LIST]There’s lots of interesting reading about interviewing developers. Joel Spolsky wrote a lengthy article about it a while ago http://www.joelonsoftware.com/articles/GuerrillaInterviewing3.html

If you want to test all these skills (PHP, MySQL, HTML, CSS, JavaScript), then try

Tests for Geeks

It has two complex tests:


HTML, CSS and JavaScript

It’s not practical tests. It’s quiz, but it could be really good alternative if you want to cover all skills.
I am not sure, that practical test can cover all these skills. To achieve this, you need to provide really big practical task. Not every developer will agree no do it.