NTTMCL hiring again

I guess it comes as no surprise since it seems like everyone is hiring these days, but NTTMCL is hiring again. Of particular interest (to me at least, since it is replacing my position) is the Unix Kernel Developer. I know, you wouldn't know it from my blog posts, but originally I was hired as a FreeBSD kernel developer. Since I am being transferred to Tokyo in a couple of months, and they don't really have the infrastructure in the office over there for kernel development, NTTMCL is hiring a kernel developer to replace me here in the Bay Area.

I don't know who wrote the job description, but there appear to be some typographical errors in it. For example, "enhanced 3 switch" should probably read "enhanced layer 3 switch" and "stabilize the developed wireless network system" should probably be "stabilize the existing wireless network system". Did I mention that NTTMCL is a subsidiary of a Japanese company? We have lots of non-native speakers.

Anyway, besides the kernel developer position, we also have a position open in our security research group, and two positions in our IP technologies group (formerly the IPv6 group) [1, 2]. If you are really into researching and playing with the latest hardware, we have a position in our Business Development group that will get to check out all of the latest gear that NTT Communications might be interested in.

We're a relatively small research and development subsidiary of NTT; currently we have about 35 people, the majority of which are software engineers of some sort. We have offices in both San Mateo, CA and San Jose, CA. The work environment is kind of a mix of big-company and startup: we're small and work with many cutting-edge technologies, but our income is stable being that we are a wholly-owned subsidiary of one of the largest ISPs in the world. There are no stock options, but there are also no 18-hour work days.

Anyway, I really like it here. In my 5 and half years here, I've worked on everything from FreeBSD kernel programming low-level networking, and implementing high-performance Un*x daemons (all in C, of course), to perl and embedded perl interpreters, to web application development (both with and without AJAX), to developing GUI-based applications on Windows using python. If you really like learning and applying new technologies, this is a great place to do so without having to worry about where your next paycheck is coming from.

If that sounds good to you too, send a copy of your resume to jobs@nttmcl.com.

Update 2007/08/16 07:07pm:

I got most of the errors in the job description for the kernel programmer corrected with H.R.; I haven't checked the others, though. Speaking of which, we're up to seven open positions now. Bring some friends! :)

NTTMCL is hiring

NTTMCL is looking for software engineers (but then, who isn't right now?). We are a small research-and-development subsidiary of NTT Communications of Japan. I won't rehash our company profile because it is all on our web site.

We use and develop a lot of different technologies, so while the current positions are focused on wireless, encryption, and VoIP, one of the great things about working at NTTMCL is that you have the chance to work on many different projects beyond those you were originally hired for. I will add that we are far more focused on development than research, with the proportion of full-time engineers to full-time researchers somewhere around 5:1.

The positions ask for C, C++, or Java experience, but we also have at least as much Python and Perl code in use on various projects. Which is to say that being flexible is quite an asset here at NTTMCL. Just knowing/using languages isn't the point: the point is having a large tool chest to pull from and being able to identify which tool is the best tool for a job. Being a R&D company, management is relatively open to trying new tools/languages/etc. if you can justify the choice by explaining how it gets the job done better than the alternatives.

Speaking of which, I've been meaning to write up a post about how much I like my job, but it turns out my co-worker Zach has already beaten me to it. Hopefully, I'll still get around to writing up my own thoughts based on my 5+ years at NTTMCL sometime soon.

Brain-teasers make bad interview questions

The other day BitTorrent posted a job posting to the BayPiggies mailing list with the following brain-teaser to solve in it:

What is the exponent of the largest power of two whose base seven representation doesn't contain three zeros in a row?

Normally, I hate "brain-teaser" type interview questions. I make it a point to never ask brain-teasers in interviews and don't put too much weight on candidates' answers when my fellow hiring managers ask them. The reason is simple: the typical brain-teaser is too easy to game.

Take BitTorrent's question, for example, the answer is 8833.

BitTorrent asked for python code to solve the problem, but that is a red-herring. You cannot solve the problem in python. Sure, you could write a program like the following that prints all of the powers of 2 that do not have three consecutive zeros in the base-7 representation:

    def base7(x):
       digits = []
       while x != 0:
           x, r = divmod(x, 7)
           digits.append(str(r))
       return ''.join(reversed(digits)) or '0'

   i, x = 0, 1
   while True:
       if '000' not in base7(x):
           print i,
       i += 1
       x += x

But BitTorrent asked for the largest power of two that meets the requirements. How do you know when a number printed by the above program is the largest? You don't! There are infinitely many numbers and this program has to test them all. That'll take a while.

The full solution to BitTorrent's problem requires you to find the upper-bound of the search -- which can only be done without a single line of python code (despite their requirement to use python): you have to solve it using math. Which implies that BitTorrent actually wants their ideal candidate to be a mathematician first and foremost. That isn't necessarily a bad thing; I don't know anything about BitTorrent's business, maybe they need people with particularly strong math backgrounds (much stronger than mine, that is).

But there is actually another way to obtain the solution: use Google. So knowing how to work a search engine will get you in the door just as effectively as having an advanced math degree. Go figure.

Neither skill says anything about the candidate's programming ability or knowledge of python in particular. In fact, I would argue that attempting to "solve" the problem by writing a python program without including the proof supporting your solution should disqualify the candidate as demonstrating that they don't understand the problem. Writing code without understanding the problem is well into Code Cowboy territory.

Anyway, the point I wanted to make was that it has been my experience with "brain-teasers" that at best they give the interviewer some vague idea of the candidate's problem-solving ability. Far more often, however, they randomly filter out people who may be perfectly good programmers but who didn't happen to have memorized (or found online) the answer to the particular brain-teaser you throw at them.

When I do interviews, I figure I only have a limited time to interview a potential employee. I would rather spend that time asking questions specific to software engineering, computer programming, or the problem domain we are hiring for. I always prepare a progression of real-world questions ranging from "easy" to "guru", with no expectation to ever ask the "guru" questions -- my intention is to see what the candidate's level of ability is and, more importantly, to see how they handle a question or two slightly beyond their ability. Maybe it's because I'm not too bright myself, but that tells me much more about the candidate's suitableness for a position than an abstract brain-teaser ever does.